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The Value of Oxygen Desaturation Index for Diagnosing Obstructive Sleep Apnea: A Systematic Review
Abstract
Objectives
Intermittent hypoxemia is a risk factor for developing complications in obstructive sleep apnea (OSA) patients. The objective of this systematic review was to identify articles evaluating the accuracy of the oxygen desaturation index (ODI) as compared with the apnea–hypopnea index (AHI) and then provide possible values to use as a cutoff for diagnosing adult OSA.
Study Design
Systematic Review of Literature.
Methods
PubMed, the Cochrane Library, and SCOPUS databases were searched through November 2019.
Results
Eight studies (1,924 patients) met criteria (age range: 28–70.9 years, body mass index range: 21.9–37 kg/m², and AHI range: 0.5–62 events/hour). Five studies compared ODI and AHI simultaneously, and three had a week to months between assessments. Sensitivities ranged from 32% to 98.5%, whereas specificities ranged from 47.7% to 98%. Significant heterogeneity was present; however, for studies reporting data for a 4% ODI ≥ 15 events/hour, the specificity for diagnosing OSA ranged from 75% to 98%, and only one study reported the positive predictive value, which was 97%. Direct ODI and AHI comparisons were not made because of different hypopnea scoring, different oxygen desaturation categories, and different criteria for grading OSA severity.
Conclusion
Significant heterogeneity exists in studies comparing ODI and AHI. Based on currently published studies, consideration should be given for diagnosing adult OSA with a 4% ODI of ≥ 15 events/hour and for recommending further evaluation for diagnosing OSA with a 4% ODI ≥ 10 events/hour. Screening with oximetry may be indicated for the detection of OSA in select patients. Further study is needed before a definitive recommendation can be made. Laryngoscope, 2020
... However AHI has several limitations and controversies still exist as to relevant definitions. [27][28][29] The oxygen desaturation index (ODI) is a count of the number of times per hour that oxygen desaturates by a certain percentage (such as 4%) and has been validated as an alternative measure and is considered to have high reproducibility and to be more relevant in a clinical setting compared to AHI. 29 In this study we used in-the-home, overnight pulse oximetry, as an objective measurement of nocturnal hypoxia, to investigate the association between nocturnal hypoxia, as measured by ODI, and AMD. We assessed if there was an association with AMD, AMD severity and the high-risk AMD sub-phenotype with coexistent RPD. ...
... 34 For the analysis of the associations with the ODI (described further below), all eligible readings from each participant across the three nights were included. The mean ODI values from the all nights of recordingsused to define the severity of OSAwas thus categorised as follows: normal (<5 episodes of >4% drop in SpO 2 from baseline per hour), mild, 5-15 moderate, [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] or severe (>30 episodes) nocturnal hypoxia. 27 ...
... The mean ODI values from the all nights of recordingsused to define the severity of OSAwas thus categorised as follows: normal (<5 episodes of >4% drop in SpO 2 from baseline per hour), mild, 5-15 moderate, [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] or severe (>30 episodes) nocturnal hypoxia. 27 ...
Background:
Nocturnal hypoxia is common, under-diagnosed and is found in the same demographic at risk of age-related macular degeneration (AMD). The objective of this study was to determine any association between nocturnal hypoxia and AMD, its severity, and the high-risk sub-phenotype of reticular pseudodrusen (RPD).
Methods:
This cross-sectional study included participants aged ≥50 years with AMD, or normal controls, exclusive of those on treatment for obstructive sleep apnoea. All participants had at home, overnight (up to 3 nights) pulse oximetry recordings and multimodal imaging to classify AMD. Classification of Obstructive Sleep Apnea (OSA) was determined based on oxygen desaturation index [ODI] with mild having values of 5-15 and moderate-to-severe >15.
Results:
A total of 225 participants were included with 76% having AMD, of which 42% had coexistent RPD. Of the AMD participants, 53% had early/intermediate AMD, 30% had geographic atrophy (GA) and 17% had neovascular AMD (nAMD). Overall, mild or moderate-to-severe OSAwas not associated with an increased odds of having AMD nor AMD with RPD (p ≥ 0.180). However, moderate-to-severe OSA was associated with increased odds of having nAMD (odds ratio = 6.35; 95% confidence interval = 1.18 to 34.28; p = 0.032), but not early/intermediate AMD or GA, compared to controls (p ≥ 0.130). Mild OSA was not associated with differences in odds of having AMD of any severity (p ≥ 0.277).
Conclusions:
There was an association between nocturnal hypoxia as measured by the ODI and nAMD. Hence, nocturnal hypoxia may be an under-appreciated important modifiable risk factor for nAMD.
... The AASM criteria for OSA diagnosis is RDI ≥ 5, if daytime sleepiness is present, and RDI ≥ 15 if not. The ODI is a clinically informative measure on the frequency of drops in oxyhemoglobin saturation levels, a marker of intermittent hypoxemia, which has been associated with poor cardiovascular outcomes, including elevated stroke risk, and increased risk of mortality [46][47][48]. ...
... Furthermore, nadir blood oxyhemoglobin saturation level, mean blood oxyhemoglobin saturation, duration of time spent with < 90% blood oxyhemoglobin saturation, and periodic leg movements during sleep index (PLMSI; number of PLMs per hour) were analyzed. These measures besides PLMSI, also reflects the degree of hypoxemia that occurs during sleep, and are additionally diagnostically important for OSA [45,47]. This study included participants with and without OSA and used the clinical measures of OSA as continuous variables for statistical analyses. ...
Background
Obstructive sleep apnea (OSA) increases risk for cognitive decline and Alzheimer’s disease (AD). While the underlying mechanisms remain unclear, hypoxemia during OSA has been implicated in cognitive impairment. OSA during rapid eye movement (REM) sleep is usually more severe than in non-rapid eye movement (NREM) sleep, but the relative effect of oxyhemoglobin desaturation during REM versus NREM sleep on memory is not completely characterized. Here, we examined the impact of OSA, as well as the moderating effects of AD risk factors, on verbal memory in a sample of middle-aged and older adults with heightened AD risk.
Methods
Eighty-one adults (mean age:61.7 ± 6.0 years, 62% females, 32% apolipoprotein E ε4 allele (APOE4) carriers, and 70% with parental history of AD) underwent clinical polysomnography including assessment of OSA. OSA features were derived in total, NREM, and REM sleep. REM-NREM ratios of OSA features were also calculated. Verbal memory was assessed with the Rey Auditory Verbal Learning Test (RAVLT). Multiple regression models evaluated the relationships between OSA features and RAVLT scores while adjusting for sex, age, time between assessments, education years, body mass index (BMI), and APOE4 status or parental history of AD. The significant main effects of OSA features on RAVLT performance and the moderating effects of AD risk factors (i.e., sex, age, APOE4 status, and parental history of AD) were examined.
Results
Apnea–hypopnea index (AHI), respiratory disturbance index (RDI), and oxyhemoglobin desaturation index (ODI) during REM sleep were negatively associated with RAVLT total learning and long-delay recall. Further, greater REM-NREM ratios of AHI, RDI, and ODI (i.e., more events in REM than NREM) were related to worse total learning and recall. We found specifically that the negative association between REM ODI and total learning was driven by adults 60 + years old. In addition, the negative relationships between REM-NREM ODI ratio and total learning, and REM-NREM RDI ratio and long-delay recall were driven by APOE4 carriers.
Conclusion
Greater OSA severity, particularly during REM sleep, negatively affects verbal memory, especially for people with greater AD risk. These findings underscore the potential importance of proactive screening and treatment of REM OSA even if overall AHI appears low.
... OSAS was considered absent when the OAHI was <5/h and present when the OAHI was ≥5/h. The OSAS group included mild (OAHI of [5][6][7][8][9][10][11][12][13][14], moderate (OAHI of [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29], and severe (OAHI of ≥30) OSAS cases [13]. ...
... Some experts have questioned the definition of OSAS based only on the OAHI, as the OAHI may not be the most reliable indicator of OSAS severity. A new definition of OSAS could include the oxygen desaturation index (ODI) [20]. Cai et al. supported the inclusion of the oxygen saturation in the definition of OSAS, as their results showed a negative correlation between the perifoveolar PD and the lowest hemoglobin oxygen saturation [3]. ...
Background and Objectives: Given the conflicting data available in the literature, this study aimed to investigate the impact of obstructive sleep apnea syndrome (OSAS) on the macular vascular density (VD) and perfusion density (PD). Materials and Methods: Based on the obstructive apnea–hypopnea index (OAHI), 61 prospectively recruited patients were assigned to either a control group (n = 12; OAHI < 5/h) or an OSAS group (n = 49; OAHI ≥ 5/h). The macular VD and PD of the superficial and deep capillary plexuses (SCP and DCP, respectively) were measured in the parafoveolar and perifoveolar areas using Zeiss PLEX Elite 9000 (6 × 6 mm). The values were compared between the control and OSAS groups. Results: Compared with the control group, the OSAS group demonstrated an increased VD of the DCP in the parafoveolar and perifoveolar areas and PD of the DCP in the perifoveolar area. No significant differences in either the macular VD or PD of the SCP were observed. There was no correlation between the OAHI and macular VD or PD. Conclusions: This study indicates that collateral vessel formation and possible retinal vasodilation occur in the DCP of patients with OSAS.
... The sleep apnea syndrome (SAS) is a sleeping disorder characterized by recurring cessations of airflow during sleep, leading to a number of complaints, such as daytime sleepiness, concentration problems, and risk of cardiovascular diseases (Rundo, 2019). Recurrent breathing cessation leads to the reduction of the blood oxygen level and eventually hypoxemia (Rashid et al., 2021). Episodes of hypoxemia during sleep are referred to as oxygen desaturation events (Smith et al., 1996). ...
... The prevalence of desaturation events is summarized in the oxygen desaturation index (ODI), which is the average number of desaturation events (Temirbekov et al., 2018). The ODI, together with the apnea-hypopnea index (AHI), is one of the two most important indicators for the severity of SAS (Rashid et al., 2021). ...
Recurrent nocturnal breathing cessation leads to the reduction of the blood oxygen level and eventually to oxygen desaturation. Oxygen desaturation events are traditionally detected during a polysomnography in a sleep laboratory. In this work, a contactless camera-based oxygen desaturation detection and oxygen desatu-ration index (ODI) estimation method based on the analysis of multispectral videos is proposed. The method is based on the extraction and analysis of remote photoplethysmography (rPPG) signals at wavelengths of 780 nm and 940 nm from the forehead and a breath temperature signal via far-infrared (FIR) thermography from the subnasal region. A manual feature extraction is designed to extract relevant medical and physiological parameters out of the aforementioned signals in order to design a Feed-Forward Neural Network (FFNN)-based classifier, which classifies between periods with and without desaturation events. For the evaluation of the proposed method, a patient dataset i nvolving 23 symptomatic sleep apnea patients is collected. The classification accuracy between desaturation events and periods without a desaturation based on the leave-one-patient-out cross-validation (LOPOCV) metric is 95.4 %. The ODI stage estimation resulted in a correct estimation in 22 out of 23 patients for a two-stage ODI classification and in a correct estimation in 21 out of 23 patients for a four-stage ODI classification.
... These assess oxygen desaturation severity during sleep and correlate with AHI (7-9). Higher AHI often means lower MSaO 2 and LSaO 2 , higher TST-SpO 2 <90%, and higher ODI, indicating more severe OSAHS (7,10). However, there are currently few studies exploring these metrics in high-altitude areas, especially in mainland China. ...
... Moreover, the mild high altitude itself can pose health risks, such as the development of OSAHS (11)(12)(13). Several other measures, including SpO 2 and ODI values, are important when evaluating the impact of OSAHS on a patient's health (7)(8)(9)(10). In this study, we analyzed associations between AHI levels and ODI, LSpO 2 , MSpO 2 , and TST-SpO 2 <90% values by regression analysis. ...
Background
Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common sleep disorder. The lower atmospheric pressure and decreased oxygen levels of high-altitude areas can exacerbate the severity of OSAHS, but research into OSAHS in high-altitude areas remains limited. This study, from June 2015 to January 2020, involved 4,667 patients with suspected OSAHS and 38 healthy volunteers. The non-OSAHS group (AHI <5/h) had 395 patients, while the larger OSAHS group (AHI ≥5/h) comprised 4,272 patients. The significant size difference between the groups emphasized the study’s focus on OSAHS, using the non-OSAHS mainly for comparison.
Methods
Sleep technicians monitored the OSAHS patient group overnight by polysomnography (PSG), the apnea-hypopnea index (AHI), the mean oxygen saturation (MSpO2), lowest oxygen saturation (LSpO2), the oxygen desaturation index (ODI) and the total sleep time with oxygen saturation less than 90% (TST-SpO2 <90%). Healthy volunteers self-monitored sleep patterns at home, using the CONTEC RS01 respiration sleep monitor with a wristwatch sleep apnea screen meter. The RSO1 wristwatch-style device has already been studied for consistency and sensitivity with the Alice-6 standard multi-lead sleep monitor and can be used for OSAHS screening in this region.
Results
LSpO2 recordings from healthy volunteers (86.36 ± 3.57%) and non-OSAHS (AHI <5/h) cohort (78.59 ± 11.99%) were much lower than previously reported normal values. Regression analysis identified no correlations between AHI levels and MSpO2 or TST-SpO2 <90%, weak correlations between AHI levels and LSpO2 or MSpO2, and a strongly significant correlation between AHI levels and the ODI (r = 0.76, p < 0.05). The data also indicated that the appropriate clinical thresholds for OSAHS patients living at mild high altitude are classified as mild, moderate, or severe based on LSpO2 saturation criteria of 0.85–0.90, 0.65–0.84, or <0.65, respectively.
Conclusion
The study findings suggest that individuals with an AHI score below 5 in OSAHS, who reside in high-altitude areas, also require closer monitoring due to the elevated risk of nocturnal hypoxia. Furthermore, the significant correlation between ODI values and the severity of OSAHS emphasizes the importance of considering treatment options. Additionally, the assessment of hypoxemia severity thresholds in OSAHS patients living in high-altitude regions provides valuable insights for refining diagnostic guidelines.
... Systolic peak detection is demonstrated in the same as QRS peak detection of ECG [33]. Three linear features in time-domain are computed such as: Upper Quartile (uQ), Middle Quartile (MQ) and Lower Quartile (LQ) in a series with Oxygen Desaturation index (ODI: 01-14) below 4% [34]. In total, 14 features have extracted from one SpO 2 signal. ...
... In such complexity, RBF-SVM projects the features data into a higher dimensional space by using RBF kernel. BY optimizing the trade-off between maximizing the margin between two different (OSA, non-OSA) classes and minimizing the classification error, the decision boundary of RBF-SVM can serve as a potent toll to discriminate subjects with or without OSA [34]. In this study, the hyperparameters of RBF optimized with grid search are adjusted and tuned in such a wise manner. ...
Obstructive Sleep Apnea (OSA) is a crucial sleep-breath disorder often characterized by partial or complete cessation of airflow during sleep. The syndrome has a hazard effect on other physiological functions causing primary risk of fragmented sleep which is a part of Sleep Apnea Syndrome (SAS), headache and morning sickness. As secondary risks, there is a high chance of vehicular accidents, cardiac failure and stroke. For the diagnosis of OSA, polysomnography (PSG) is considered as the gold standard strategy that records and analyzes brain waves, heart rate, breathing pattern, oxygen level and artifacts of the survival. This paper uses a multi-modal approach by considering both ECG and SpO2 signals. Feature extractions of both the signals are carried out to extract time–frequency domain features and spatial features. Then, the extracted features are combined at a feature-level fusion technique. Finally, the fused features are fed to a series of machine learning classifiers such as Decision Tree (DT), Random Forest (RF) and Radial Basis Function-based Support Vector Machine (RBF-SVM). Comparing the classification performances, accuracy of RBF-based SVM outperformed other two classifiers with a score of 98.60%. Therefore, our proposed methodology can be considered for automated classification of OSA and non-OSA subjects.
... The recently introduced SWs can serially measure oxygen saturation during sleep using reflective PPG, so it theoretically possible to detect hypoxia, which is often accompanied by sleep-related breathing disorders. Although diagnosis of OSA syndrome (OSAS) is not made by the severity of oxygen desaturation, but by apnea or hypopnea episodes per hour, a few studies have suggested that the oxygen saturation-related index in patient with OSA is significantly associated with the apnea-hypopnea index (AHI), and oxygen-related parameters can be helpful in diagnosing and assessing the severity of OSAS [11][12][13]. ...
... Although AHI is the only criterion for diagnosing OSA and assessing its severity, but oxygen saturation can also be a useful parameter, as hypoxia is known to impair physiological and cognitive function [13]. In supporting studies, there are reports that there is a correlation between oxygen desaturation index (ODI) and AHI, or that oxygen desaturation may better reflect the severity of OSA symptoms [11,12]. ...
Background and Objectives Considering the prevalence and health effects of obstructive sleep apnea (OSA), early diagnosis and proper treatment are essential. Polysomnography (PSG) has limitations in diagnosing or tracking large-scale OSA patients. Smartwatches (SWs) can be equipped with a photoplethysmograph (PPG) that can indirectly measure heart rate and blood oxygen saturation by detecting the difference of light absorption through blood. The purpose of this study is to compare oxygen saturation parameters of PPG-based SWs with those of PSG to determine the diagnostic accuracy for OSA. Methods After obtaining voluntary consent from patients who were scheduled to undergo PSG in a sleep clinic due to suspected OSA, they were randomly assigned to wear a Galaxy watch4 (GW) or Apple watch7 (AW) on their wrist. The agreement rates between the oxygen saturation parameters of the two SW types and PSG were evaluated. The accuracy, sensitivity, and specificity of the oxygen saturation parameters for diagnosis of OSA (apnea-hypopnea index [AHI] ≥5/h) were compared between the two types of SW. Results A total of 133 patients underwent PSG while wearing an SW. Including duplicates, 109 patients wearing a GW and 69 wearing an AW were included. The diagnostic accuracy of AHI ≥5/h according to oxygen saturation time measured by a GW was less than 90%, the respective sensitivity and specificity were 82.9% and 75.8%. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was 0.807 (p
... When breathing is obstructed during sleep, the blood oxygen levels drop. Therefore, it can identify apnea and hypopneas well [9]. ...
... Therefore, overnight oximetry seems to be an inexpensive, readily available, and straightforward tool to screen for OSA. Previous studies have also emphasized the accuracy of ODI as a tool to detect SBD and suggested it should be an essential assessment criterion for diagnosis [9,27,28]. Mashaqi et al. [29] found that the use of nocturnal oximetry measures (ODIPOx) improved the accuracy of SBQ in severe OSA in both inpatient and outpatient settings. Our study also showed this; however, the cost of improving the diagnostic ability of SBQ reduced the diagnostic ability of the ODI. ...
Purpose
Despite polysomnography being the gold standard method of diagnosing obstructive sleep apnea (OSA), it is time-consuming and has long waiting lists. Alternative methods including questionnaires and portable sleep devices have been developed to increase the speed of diagnosis. However, most questionnaires such as the STOP-BANG questionnaire (SBQ) are limited due to low specificity. This study evaluated the value of SBQ to screen for OSA and compared it with the oxygen desaturation index (ODI) and their combination.
Methods
This retrospective study included patients who completed the SBQ and underwent a night at the sleep lab or home sleep testing. The ODI was extracted from these sleep study reports. The combination of SBQ with ODI and their individual scores were compared with apnea–hypopnea index (AHI) in terms of their accuracy in diagnosing OSA. Sensitivity, specificity, and area under the curve (AUC) for different severities of OSA were calculated and compared.
Results
Among 132 patients, SBQ showed a sensitivity of 0.9 and a specificity of 0.3 to screen for OSA. As the severity of OSA increased, the sensitivity increased whilst specificity decreased for both measurements. ODI achieved an increased specificity of 0.8 and could correctly diagnose OSA 86% of the time which was better than SBQ’s 60%. For all severities of OSA, ODI alone displayed a larger AUC than SBQ and similar AUC to their combination.
Conclusion
ODI produced a higher specificity and AUC than SBQ. Furthermore, ODI combined with SBQ failed to increase diagnostic value. Therefore, ODI may be the preferred way to initially screen patients for OSA as an easy-to-use alternative compared to SBQ.
... Simpler OSA diagnostic methods, which can be easily repeated at home, also have the potential to address a well-reported but largely ignored phenomenon in clinical practice, which is OSA severity night-to-night variability 15 . However, the performance of oximeters is variable and dependent on the technology used, and the method is not disseminated and is usually considered a screening diagnostic tool 16 . We recently validated a new high-resolution wireless oximeter with a smartphone application and an automated cloud algorithm for the detection of oxygen desaturation, described herein as overnight digital monitoring (ODM-Biologix) 14 . ...
... However, only three of them performed simultaneous monitoring of PSG and ODM. The authors concluded that overnight oximetry was adequate to detect moderate to severe OSA when the 4% desaturation criterion was used 16 . We have previously shown a good performance of ODM-Biologix when compared to the sleep laboratory PSG-AHI 14 . ...
Obstructive sleep apnea (OSA) is extremely common and has several consequences. However, most cases remain undiagnosed. One limitation is the lack of simple and validated methods for OSA diagnosis at home. The aim of this study was to validate a wireless high-resolution oximeter with a built-in accelerometer linked to a smartphone with automated cloud analysis (Biologix) that was compared with a home sleep test (HST, Apnea Link Air) performed on the same night. We recruited 670 patients out of a task force of 1013 patients with suspected OSA who were referred to our center for diagnosis. The final sample consisted of 478 patients (mean age: 56.7 ± 13.1 years, mean body mass index: 31.9 ± 6.3 kg/m2). To estimate the night-to-night OSA severity variability, 62 patients underwent HST for two consecutive nights. The HST-apnea–hypopnea index (AHI) and the Biologix-oxygen desaturation index (ODI) was 25.0 ± 25.0 events/h and 24.9 ± 26.5 events/h, respectively. The area under the curve—sensibility/specificity to detect at least mild (HST-AHI > 5), moderate-to-severe (HST-AHI > 15), and severe OSA (HST-AHI > 30) were (0.983)—94.7/92.8, (0.986)—94.8/93.9, and (0.990)—95.8/94.3, respectively. The limits of agreement originating from the Bland–Altman plot and the correlation between HST-AHI and Biologix-ODI were lower than the night-to-night HST-AHI variability (25.5 and 34.5 events/h, respectively, p = 0.001). We conclude that Biologix is a simple and reliable technique for OSA diagnosis at home.
... Surgical interventions significantly reduce AHI and result in a significant percent reduction, similar to CPAP, suggesting their role in addressing OSA in non-CPAP adherent patients alongside improving subjective outcomes. Another important point is that AHI as an outcome might not be the best metric to evaluate OSA severity [38]. The comparable reduction in AHI and depression PROMs highlights this fact. ...
Purpose
To evaluate the effect of CPAP and surgical alternatives for OSA on depression and compare the results of surgery to CPAP.
Methods
COCHRANE Library, CINAHL, PubMed, and Scopus databases were searched for English-language articles. Meta-analysis of continuous measures (mean), proportions (%), and mean difference (Δ) with 95% confidence interval was conducted for objective and subjective outcomes before and after treatment with CPAP or surgical interventions.
Results
We identified 2018 abstracts, 14 studies (N = 3,488) were included in the meta-analysis. Both treatments witnessed significant improvement in Apnea-hypopnea Index (AHI), with similar improvement with CPAP (Δ-48.8 [-51.2, -46.4]) and surgical interventions (Δ -20.22 [-31.3, -9.17]). An improvement in Epworth Sleepiness Scale (ESS) was noted between groups with (Δ -3.9 [-6.2, -1.6]) for the CPAP group and (Δ -4.3 [-6.0, -2.5]) for surgical interventions. The improvement of BDI II depression scores pre- and post-treatment was comparable between treatments with (Δ -4.1 [-5.8, -2.4]) for the CPAP group and (Δ- 5.6 [-9.2, -2.0]) for surgical interventions.
Conclusion
Our findings suggest a reduction in AHI is seen in both CPAP and surgical interventions for OSA, with no difference in AHI reduction between groups. Both treatments also lead to a similar improvement in depression scores providing strong evidence regards impact of surgery on OSA-associated mood disorders. While percent reduction in depression is higher in the surgical group, the difference did not reach statistical significance when compared to CPAP. When stratified by surgical intervention, most interventions suggest an improvement in depression scores.
... These factors can contribute to long-term health complications such as impaired endothelial function, elevated blood pressure, and increased risk for cardiovascular and metabolic disorders. [46][47][48] In terms of daily life, the increased severity of OSA in the NPOSA group may result in more pronounced daytime symptoms, including excessive daytime sleepiness, impaired cognitive function, and behavioral problems. Chronic sleep disruption and intermittent hypoxia can affect children's mood, academic performance, and overall quality of life. ...
Purpose
This study investigates the prevalence, risk factors, and clinical characteristics of positional obstructive sleep apnea (POSA) among pediatric patients diagnosed with obstructive sleep apnea (OSA).
Patients and Methods
A total of 1,236 children aged 0 to 17 years who underwent nocturnal polysomnography (PSG) and completed the Sleep Questionnaire were included. After excluding those with an AHI <1, neurological or muscular disorders, or insufficient sleep time in specific positions, 908 patients remained: 158 with POSA and 750 with non-positional OSA (NPOSA). Propensity score matching (PSM) was applied at a 1:2 ratio, resulting in a final sample of 153 POSA and 306 NPOSA patients. Data analyses were performed using R software (version 4.2.3).
Results
The prevalence of POSA was 12.8%. After PSM, patients with POSA had a lower overall AHI (8.66 vs 10.30), REM-AHI (14.30 vs 17.40), and NREM-AHI (7.43 vs 8.77) compared to those with NPOSA. POSA patients also had a shorter total sleep time (411 vs 427 minutes), spent less time in the supine position (168 vs 225 minutes), and more time in non-supine positions (241 vs 202 minutes) than NPOSA patients. Additionally, while the supine AHI was higher in POSA patients (15.60 vs 10.30), the non-supine AHI was lower (5.00 vs 11.00) compared to NPOSA patients. The minimum oxygen saturation was slightly higher in POSA patients (0.88 vs 0.87). All differences were statistically significant (P < 0.05). Risk factors for POSA included mild OSA, allergic rhinitis, non-allergic rhinitis, and obesity.
Conclusion
The prevalence of POSA in children is lower than in adults, and its severity is less than that of NPOSA. Compared to NPOSA patients, POSA patients had significantly higher AHI during supine sleep and lower AHI during non-supine sleep. POSA patients also spent more time in non-supine positions, suggesting that avoiding supine sleep may help reduce apnea events. These findings highlight the importance of monitoring and managing sleep posture in POSA patients.
... Điều này cho thấy đề xuất sử dụng AHI là chỉ số giúp phân mức độ nặng OSA theo Trung tâm Nghiên cứu Y học Giấc ngủ của Mỹ năm 2009 là phù hợp [1]. Ngoài ra, OSA cũng có mối tương quan với chỉ số AHI và chỉ số ODI đã được chứng minh qua rất nhiều nghiên cứu [1], [7]. ...
Mục tiêu nghiên cứu: Nghiên cứu nhằm đánh giá mối tương quan giữa một số thông số giảm oxy máu về đêm với HbA1c ở bệnh nhân đái tháo đường típ 2. Đối tượng và phương pháp nghiên cứu: Nghiên cứu mô tả cắt ngang được tiến hành trên 96 bệnh nhân đái tháo đường típ 2 tại Bệnh viện Trường Đại học Y dược Cần Thơ từ tháng 03 năm 2023 đến tháng 3 năm 2024. Kết quả: Về đặc điểm chung, nữ giới chiếm đa số (64,6%), tuổi trung bình là 67,31 ± 12,9 và tỷ lệ mắc OSA là 43,8%. Về đặc điểm lâm sàng, hầu hết có triệu chứng ngưng thở/nghẹt thở, thở hổn hển, thức dậy mệt mỏi, đau đầu buổi sáng (>85%). Về đặc điểm đa ký hô hấp, nhóm OSA có chỉ số AHI và chỉ số ODI cao hơn so với nhóm không OSA lần lượt là 17,41 ± 13,28 vs. 7,1 ± 13,4 và 21,35 ± 14,95 vs. 8,31 ± 14,28 (tất cả p < 0,001). Đồng thời, chỉ số SpO2 trung bình ở BN có OSA thấp hơn so với BN không có OSA (p = 0,04). Về sự tương quan, HbA1c có mối tương quan thuận với ODI và AHI, tuy nhiên các mối tương quan đều rất yếu và sự khác biệt không có ý nghĩa thống kê (tất cả 0 < r < 0,2; p > 0,05). Kết luận: Ở bệnh nhân đái tháo đường típ 2, một só triệu chứng kinh điển của OSA vẫn biểu hiện rõ. Trên đa ký hô hấp, chỉ số AHI, ODI và SpO2 trung bình đều cho thấy tình trạng thiếu oxy máu về đêm nặng hơn ở nhóm có OSA so với nhóm không mắc OSA. Nồng độ HbA1c có mối tương quan thuận với chỉ số AHI và ODI nhưng các mối tương quan thuận đều rất yếu và sự khác biệt không có ý nghĩa thống kê.
... The differential associations of childhood adversity with AHI and ODI, respectively, deserve some consideration as these metrics are highly correlated (> 0.95) with one another [14]. However, there is significant heterogeneity in studies comparing ODI and AHI [58], and studies using in-lab PSG have shown that these indicators behave differently, depending on age, BMI, and sex [59]. Specifically, growing evidence suggests that agreement between AHI and ODI disappears progressively with the increase of obesity [59], which also influences their association with CM. ...
... In relation to health outcomes, 4% ODI is independently associated with arterial hypertension 16 and in the prediction of oxidative stress, which plays an important role in the development of cardiovascular disease. 17,18 When there is a high clinical probability of OSA, ODI 4% is valid to "rule in" moderate to severe OSA (AHI ≥ 15 events/h), [19][20][21][22] and ODI is used in some countries as a metric to diagnose OSA. 1 Furthermore, there is a wealth of data that can be obtained from the pulse oximeter signal, which can have clinical utility in assessing sleep-disordered breathing. 23 The current study demonstrates that standardization of ODI indices within PSG could decrease heterogeneity between future studies. ...
Study objectives:
The oxygen desaturation index (ODI) is an important measure of sleep disordered breathing during polysomnography (PSG) however the AASM Manual (V3) does not specify whether to include oxygen desaturations occurring during wake epochs. Additionally ODI obtained from PSG can differ from ODI using home sleep apnea tests (HSAT) that do not measure sleep, hampering diagnostic and treatment decision reliability. This study aimed to (1) compare an ODI that included all desaturations to an ODI that excluded desaturations occurring during wake epochs in PSG, and (2) compare ODIs obtained from PSG to HSAT.
Methods:
100 consecutive PSGs for investigation of OSA were compared. ODIs were calculated including all desaturations (ODIall) and by excluding desaturations entirely during wake epochs (ODIsleep). Additionally, we compared ODIall to an ODI calculated using monitoring time as the denominator (ODIHSAT).
Results:
The median (IQR) 3% ODI for ODIall was 22.8/h (13.1, 44.1) and ODIsleep was 17.6/h (11.5, 35.2)/h, (median difference: -3.9/h (-8.2, -.9); 21.0% (8.7, 33.2)). This discrepancy was larger with increasing ODI and decreasing sleep efficiency. The ODIHSAT was 17.4/hr (11.3, 35.2) and the median reduction in ODIHSAT versus ODIall was -4.5/h (-10.9, -2.0): (21.6% (11.1, 33.8)).
Conclusions:
ODI was significantly reduced when desaturations in wake epochs were excluded, and when ODI was based on monitoring time rather than sleep time, with potential for underestimation of disease severity. Results suggest that ODI can differ substantially depending on the calculation and study type used, and that there is a need for standardization to ensure consistent diagnosis and treatment outcomes.
... We also found that the associations between BMI, BMI-GRS with ODI were stronger than AHI. There were multiple studies showing that ODI was a more sensitive and valuable predictor to detect OSA 41,42 which was consistent with our results. Oxygen desaturation parameters were better markers for cardiovascular disease 43 and OSA associated morbidity and mortality compared to the AHI. ...
Objective
Both obstructive sleep apnea (OSA) and obesity are highly prevalent worldwide, and are intrinsically linked. Previous studies showed that obesity is one of the major risk factors for OSA, but the causality of the relationship is still unclear. The study was to investigate the causal relationships of overall obesity and abdominal obesity with OSA and its quantitative traits.
Methods
In this case-control study, a total of 7134 participants, including 4335 moderate-to-severe OSA diagnosed by standard polysomnography and 2799 community-based controls were enrolled. Anthropometric and biochemical data were collected. Mendelian randomization (MR) analyses were performed using the genetic risk score, based on 29 body mass index (BMI)- and 11 waist-hip-ratio (WHR)-associated single nucleotide polymorphisms as instrumental variables. The causal associations of these genetic scores with OSA and its quantitative phenotypes were analyzed.
Results
Obesity was strongly correlated with OSA in observational analysis (β= 0.055, P = 3.7 × 10⁻⁵). In MR analysis, each increase by one standard deviation in BMI was associated with increased OSA risk [odds ratio (OR): 2.21, 95% confidence interval (CI): 1.62–3.02, P = 5.57 × 10⁻⁷] and with 2.72-, 4.68-, and 3.25-fold increases in AHI, ODI, and MAI, respectively (all P < 0.05) in men. However, no causal associations were found between WHR and OSA risk or OSA quantitative traits in men and women.
Conclusion
Compared to abdominal obesity, overall obesity showed a causal relationship with OSA and its quantitative traits, especially in men.
... In our study, ODI was used to diagnose OSA. ODI has been proved to be at least as useful a tool to screen, diagnose, and quantify OSA (50). However, the OSA phenotype may interfere with OSA diagnosis based on ODI alone. ...
Background
Owing to the lack of clear guidelines, the significance of obstructive sleep apnea (OSA) screening in healthy community people is unclear. This study aimed to screen for OSA in a healthy community population and provide a basis for its screening.
Methods
Permanent residents from five communities in the coastal and mountainous areas of south China were selected. The screening process included demographic and sleep questionnaire surveys, and an OSA screening. To compare the prevalence and risk factors of OSA in different areas, a type IV wearable intelligent sleep monitor (WISM) was used for screening.
Results
A total of 3,650 participants completed all studies, with a mean age of 53.81±12.71 years. In addition, 4,318 participants completed the OSA screening within 30 days, and the objective screening speed was 200 people per day. The recovery rate of the screening equipment was 99.37% (4,291/4,318), the screening success rate was 89.63% (3,846/4,291), and the rejection rate was 2.7% (120/4,438). The prevalence of high-risk OSA screened using the Stop-Bang questionnaire was 42.8% (1,563/3,650) and that screened using the device was 30.7% (1,119/3,650). The prevalence of OSA screened using the Stop-Bang questionnaire was higher than that screened using the device (P<0.01). Further analysis of sleep quality and daytime sleepiness showed that 47.6% (1,736/3,650) of the community population had good sleep quality and 6.6% (240/3,650) had daytime sleepiness. Age, sex, body mass index (BMI), neck circumference, and hypertension were risk factors for OSA in the community population.
Conclusions
The use of objective type IV sleep detection equipment to screen a large sample population in the community in a short time is feasible. The prevalence of high-risk OSA screened using the Stop-Bang questionnaire was higher than that screened using the objective screening device.
... Hypoxemia appears to better reflect the impact of OSA on the occurrence of cardiovascular and metabolic comorbidities. A recent systematic review concludes that oxygen desaturation index (ODI) (value of 4%) >15 events/h should be considered as the cut-off for diagnosing OSA with a specificity from 75 to 98% and positive predictive value of 97% (Rashid et al., 2021). ...
Obstructive sleep apnea (OSA) is a common disorder. Its prevalence is increasing worldwide, partially due to increasing rates of obesity, and OSA has a well-documented impact on physical health (increased risk of cardiovascular and metabolic disorders) and mental health, as well as major socioeconomic implications. Although continuous positive airway pressure treatment (CPAP) remains the primary therapeutic intervention for moderate to severe OSA, other treatment strategies such as weight loss, positional therapy, mandibular advancement devices (MAD), surgical treatment, myofunctional therapy of upper airways (UA) muscles and hypoglossal nerve stimulation are increasingly used. Recently, several trials have demonstrated the clinical potential for various pharmacological treatments that aim to improve UA muscle dysfunction, loop gain, or excessive daytime sleepiness. In line with the highly heterogeneous clinical picture of OSA, recent identification of different clinical phenotypes has been documented. Comorbidities, incident cardiovascular risk, and response to CPAP may vary significantly among phenotypes. With this in mind, the purpose of this review is to summarize the data on OSA phenotypes that may respond to pharmacological approaches.
... However, the quality of the primary papers were poor with large discrepancies in the definitions of almost all of the variables used in the studies. 26, level III Digital health using smart phones and portable devices had been studied to diagnose OSA. A meta-analysis with mixed quality of primary papers on sleep-related breathing disorder showed that bed/mattressbased devices had the best overall sensitivity of 0.921 (95% CI 0.870 to 0.953). ...
... Nearly 1 billion adults are affected by obstructive sleep apnea, and globally, 425 million adults aged 30-69 years have moderate to severe obstructive sleep apnea, and treatment is recommended [2]. The apnea-hypopnea index (AHI) has been most common measurement of OSA frequency and severity; it is the number of apnea and hypopneas counted per hour during sleep [3] and OSA severity is classified as mild (AHI 5.0-14.9 events/h), moderate (AHI 15.0-29.9 ...
Objectives
This study assessed the effects of obstructive sleep apnea (OSA) on mental health, health-related quality of life (HRQoL), and multimorbidity in Korean adults.
Methods
The study included 8030 participants from the Korea National Health and Nutrition Examination Survey Ⅷ (2019–2020). The risk of OSA was assessed using STOP-BANG questionnaire. Depression was measured using the Patient Health Questionnaire-9 (PHQ-9), and stress was measured using a questionnaire. HRQoL was determined by EuroQol 5-dimension (EQ-5D) and Health-related Quality of Life Instrument with 8 Items (HINT-8) scores. Multimorbidity was defined as the presence of 2 or more chronic diseases. A complex sample multivariate logistic regression analysis was conducted.
Results
Participants with a high OSA risk were more likely to a have high PHQ-9 score (OR 4.31, 95% confidence interval [CI] 2.80–6.65), total depression (OR 4.07, 95% CI 2.67–6.19) stress (OR 2.33, 95% CI 1.85–2.95), lower EQ-5D (OR 2.88, 95% CI 2.00–4.15) and HINT-8 scores (OR 2.87, 95% CI 1.65–4.98), and multimorbidity (OR 2.62, 95% CI 2.01–3.41) than participants with low OSA risk. High OSA risk was significantly associated with all EQ-5D and HINT-8 items.
Conclusions
This study adds to the few population-based studies showing associations between mental health, HRQoL, and multimorbidity using nationwide data. OSA prevention might be helpful for good mental health, improving HRQoL, and comorbidity burdens. The results provide novel insights regarding the association between sleep apnea and multimorbidity.
... However, the AHI does not consider the duration of respiratory cessations and subsequent intermittent oxygen desaturations, which seem to play an important role in the development of complications related to OSA [26]. Recently, alternative parameters such as oxygen saturation (SpO 2 ), percentage of time with SpO 2 below 90%, and oxygen desaturation index (ODI), have also been used to assess the severity of OSA [27][28][29]. In this context, the aim of our study was to examine the relation between specific haematological parameters as markers of oxidative and inflammatory stress and the degree of hypoxia, measured by AHI, ODI, and SpO 2 , in a cohort of OSA patients in order to identify promising biomarkers of the disease. ...
Background: The identification of circulating markers of oxidative stress and systemic inflammation might enhance risk stratification in obstructive sleep apnea (OSA). We investigated the association between specific haematological parameters, as easily measurable markers of oxidative stress and inflammation, and the degree of hypoxia during polysomnography using the apnea hypopnea index (AHI), oxygen desaturation index (ODI), and oxygen saturation (SpO2), in OSA patients. Methods: Associations between polysomnographic parameters and demographic, clinical, and laboratory characteristics were assessed in a consecutive series of patients with OSA attending the Respiratory Disease Unit of the University Hospital of Sassari, north Sardinia (Italy), between 2015 and 2019. Results: In 259 OSA patients (195 males and 64 females), the body mass index (BMI) was significantly and positively associated with the AHI and ODI, and negatively associated with the mean SpO2. No haematological parameter was independently associated with the AHI or ODI. By contrast, albumin, neutrophil, and monocyte counts, and the systemic inflammatory response index (SIRI) were independently associated with a lower SpO2. Conclusions: Our results suggest that albumin and specific haematological parameters are promising markers of reduced oxygen saturation in OSA.
... Most tables seem to be linked to oxygen related metrics pointing out sleeping-linked respiratory problems such as obstructive sleep apnea (OSA). This is the case of the four tables e origin_osa_event, origin_osa_process, osa_event and osa_process e whose name includes OSA, and also of the table ODI, with ODI corresponding to Oxygen Desaturation Index, a metric used to assess obstructive sleep apnea (Rashid et al., 2021). All these features are linked to the monitoring of sleepbreathing quality. ...
This paper studies the post-mortem digital forensic artifacts left by the Android Zepp Life (formerly Mi Fit) mobile application when used in conjunction with a Xiaomi Mi Band 6. The Mi Band 6 is a low-cost smart band device with several sensors that allow for health and activity monitoring, collecting metrics such as heart rate, blood oxygen saturation level, and step count. The device communicates via Bluetooth Low Energy with the Zepp Life application, which displays its data, provides some controls, and acts as a bridge to the Internet. We study, from a digital forensics perspective, the Android version of the mobile application in a rooted smartphone. For this purpose, we analyze the data repositories, namely its databases and XML files, and correlate the data on the smartphone with the corresponding usage of the Mi Band device. The paper also presents two open-source scripts we have developed to ease the task of forensic practitioners dealing with Zepp Life/Mi Band 6: ZL_std and ZL_autopsy. The former refers to a Python 3 script that extracts high-level views of Zepp Life data through the command-line, whereas the latter is a module that integrates ZL_std functionalities within the popular open-source Autopsy digital forensic software. Data stored on the Android companion device of a Mi Band 6 might include GPS coordinates, events and alarms, and biometric data such as heart rate, sleep time, and fitness activity, which can be valuable digital forensic artifacts.
Anyone clicking on this link before June 30, 2023 will be taken directly to the final version of the article:
https://authors.elsevier.com/a/1h3bj9UFWM%7E7T1
... 8 Finally, the oxygen desaturation index (ODI) quantifies the number of oxygen desaturation events, 9 and it is the most suitable parameter to measure intermittent hypoxia. 10 In sum, the three parameters are complementary to each other because they capture different dimensions of OSA. ...
Background:
Obstructive sleep apnea (OSA) is a common sleep-breathing disorder linked to increased risk of cardiovascular disease. Intermittent hypoxia and intermittent airway obstruction, hallmarks of OSA, have been shown in animal models to induce substantial changes to the gut microbiota composition and subsequent transplantation of fecal matter to other animals induced changes in blood pressure and glucose metabolism.
Research question:
Does obstructive sleep apnea in adults associate with the composition and metabolic potential of the human gut microbiota?
Study design and methods:
We used respiratory polygraphy data from up to 3,570 individuals aged 50-64 from the population-based Swedish CardioPulmonary bioImage Study combined with deep shotgun metagenomics of fecal samples to identify cross-sectional associations between three OSA parameters covering apneas and hypopneas, cumulative sleep time in hypoxia and number of oxygen desaturation events with gut microbiota composition. Data collection about potential confounders was based on questionnaires, on-site anthropometric measurements, plasma metabolomics, and linkage with the Swedish Prescribed Drug Register.
Results:
We found that all three OSA parameters were associated with lower diversity of species in the gut. Further, the OSA-related hypoxia parameters were in multivariable-adjusted analysis associated with the relative abundance of 128 gut bacterial species, including higher abundance of Blautia obeum and Collinsela aerofaciens. The latter species was also independently associated with increased systolic blood pressure. Further, the cumulative time in hypoxia during sleep was associated with the abundance of genes involved in nine gut microbiota metabolic pathways, including propionate production from lactate. Lastly, we observed two heterogeneous sets of plasma metabolites with opposite association with species positively and negatively associated with hypoxia parameters, respectively.
Interpretation:
OSA-related hypoxia, but not the number of apneas/hypopneas, is associated with specific gut microbiota species and functions. Our findings lay the foundation for future research on the gut microbiota-mediated health effects of OSA.
... Overnight pulse oximetry (ONO) during sleep has inconsistent sensitivity in the outpatient setting and is not recommended as a primary screening method for OSA [50,51]. ONO can be used to calculate the oxygen desaturation index (ODI), which refers to the number of events per hour with a fall in oxygen saturation from baseline by a predefined percentage (3-4%; ODI 3% and ODI 4%) [52,53]. ODI may be comparable to AHI for the diagnosis of OSA in an inpatient setting [25]. ...
Obstructive sleep apnea (OSA) is highly prevalent in the general population. In addition, patients with comorbid OSA are frequently hospitalized for unrelated conditions. This review focuses on managing patients with comorbid OSA in inpatient and acute care settings for inpatient providers. OSA can impact the length of stay, the risk of intubation, the transfer to the intensive care unit, and mortality. Screening questionnaires such as STOP-BANG can help with screening hospitalized patients at admission. High-risk patients can also undergo additional screening with overnight pulse oximetry, which can be used to guide management. Options for empiric treatment include supplemental oxygen, continuous positive airway pressure therapy (CPAP), auto adjusting-PAP, bilevel positive airway pressure therapy (BPAP), or high-flow nasal cannula. In addition, discharge referral to a board-certified sleep physician may help improve these patients’ long-term outcomes and decrease readmission risks.
... *p < 0.05; **p < 0.01; ***p < 0.001. Michiel et al., 2015;Rashid et al., 2021). Given only two trials were included in the respiratory distress index in our meta-analysis, more trials are warranted for conclusive evidence. ...
The aims of the review are to (1) evaluate the effectiveness of wearable‐delivered sleep interventions on sleep outcomes among adults and (2) explore the effect of factors affecting total sleep time. Eight databases were searched to identify relevant studies in English without year limitations from inception until December 23, 2021. The Cochrane risk of bias tool version 2.0 and Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) criteria were used to assess the risk of bias and certainty of the evidence, respectively. Twenty randomised controlled trials (RCTs) were included, involving 1608 adults across nine countries. Wearable‐delivered sleep interventions elicited significant improvement of 1.96 events/hour for oxygen desaturation index and 3.13 events/hour for respiratory distress index. Meta‐analyses found that wearable‐delivered sleep interventions significantly decreased sleep disturbance (Hedges' g (g) −0.37, 95% confidence interval (CI): −0.59, −0.15) and sleep‐related impairment (g − 1.06, 95% CI: −1.99, −0.13) compared with the comparators. The wearable‐delivered sleep interventions may complement usual care to improve sleep outcomes. More rigorous RCTs with a long‐term assessment in a wide range of populations are warranted. This article is protected by copyright. All rights reserved.
... A apneia obstrutiva do sono (AOS) é o tipo mais comum de distúrbio respiratório relacionado ao sono [1,2], com prevalência estimada de 9-38% entre adultos, variando de acordo com sexo e aumentando com a idade [3]. O distúrbio caracteriza-se pela oclusão total ou parcial das vias respiratórias superiores [4,5], que leva a eventos repetitivos de apneia ou hipopneia associados à dessaturação-ressaturação de oxigênio [6]. Estes episódios repetitivos parecem desempenhar um papel importante no desenvolvimento de doenças cardiovasculares [7]. ...
Introdução: A apneia obstrutiva do sono (AOS) é o distúrbio respiratório do sono mais comum. O treino muscular respiratório tem surgido como uma intervenção promissora para a melhora dos sintomas e com boa adesão, porém muito ainda se tem discutido sobre sua efetividade e segurança. Objetivo: Avaliar a efetividade e segurança do TMR no tratamento de pacientes com AOS. Métodos: Para tanto, realizaremos uma revisão sistemática de ensaios clínicos randomizados (ECR). O protocolo do estudo foi registrado na Plataforma Prospero (CRD42018096980). Incluiremos indivíduos de idade superior ou igual a 18 anos, com diagnóstico de AOS, em uso ou não de pressão positiva nas vias aéreas. Excluiremos estudos com pacientes diagnosticados com lesão da medula espinhal ou doenças neuromusculares. As buscas serão realizadas nas bases de dados: Medical Literature Analysis and Retrieval System Online (Medline) via Pubmed, Excerpta Medica dataBASE (Embase) via Elsevier, Cochrane Central Register of Controlled Trials (Central) via Cochrane Library, Literatura Latino-Americana e do Caribe em Ciências da Saúde (Lilacs) via Portal da Biblioteca Virtual em Saúde e Physiotherapy Evidence Database (PEDro), sem restrições de idioma ou ano de publicação. Avaliaremos o rigor metodológico dos estudos incluídos e a certeza da evidência dos principais desfechos da revisão sistemática utilizando a ferramenta Risco de Viés 2.0 da Cochrane e a abordagem Grading of Recommendations Assessment, Development and Evaluation (GRADE), respectivamente. A seleção dos estudos, extração de dados, avaliação do viés dos estudos incluídos e avaliação da certeza da evidência serão realizados por dois pesquisadores independentes. Resultados esperados: Espera-se que os resultados desta revisão forneçam informações úteis para a tomada de decisão clínica, exponham lacunas de conhecimento, assim como forneçam um bom embasamento para futuros ECR de alta qualidade sobre o assunto.
... We found that the OSA group showed more nocturnal O 2 desaturation: higher ODI and lower minimal SpO 2 than the non-OSA group, with P value of 0.000 and P value of 0.013, respectively. Rashid et al. [38] compared the ODI and AHI in a meta-analysis of eight studies. They found that the specificity for diagnosing OSA based on 4% ODI more than or equal to 15 events/h ranged from 75 to 98%. ...
Introduction
Obstructive sleep apnea (OSA) can be presented by diverse phenotypes with or without excessive daytime sleepiness (EDS). The present study was conducted to detect the prevalence and the predictors of OSA in a sample of habitual snorers without EDS nor nocturnal observed apnea.
Patients and methods
A total of 61 adult participants complaining of habitual snoring were included in the study and subjected to OSA screening questionnaire, anthropometric measures, tonsil examination, modified Mallampati score, and full polysomnography. Univariate analysis and regression analysis were done to detect the association of OSA with participants’ characteristics and polysomnography data. The statistically significant variables were entered into the receiver operating characteristic curve to estimate the best cutoff values for predictors of OSA in habitual snorers.
Results
The studied patients were divided into two groups: 11.5% had no OSA [apnea–hypopnea index (AHI)<5], and 88.5% had OSA. AHI values were significantly greater in males compared with females [45.2 (interquartile range: 29.9–62.6) in males versus 22.1 (interquartile range: 9.6–35.9) in females, P =0.001]. There was a statistically significant positive correlation between AHI and age ( r =0.39). The best cutoff point of age to detect OSA group was more than 43 years with a sensitivity of 64.81%, specificity of 100%, and total accuracy of 0.86. The best cutoff point of BMI to detect OSA group was more than 37 kg/m ² , with a sensitivity of 46.30%, specificity of 100%, and total accuracy of 0.75.
Conclusion
OSA should be investigated in habitual snorers even in the absence of EDS and nocturnal apnea, especially in older (>43 years), obese (BMI >37 kg/m ² ), and male patients.
... Many studies have looked into oximetry data in the context of sleep apnea 29,35,47 , where the main focus is on the identification of oxygen desaturations and their correlation to the Apnea-Hypopnea Index (AHI) 46,53 . Even though there is extensive literature investigating the relationship between Oxygen saturation and sleep apnea (and the patterns that arise in SaO 2 time series), there is little or no general means of identifying the patterns investigated in this work beyond the scope of sleep studies. ...
In patients with kidney failure treated by hemodialysis, intradialytic arterial oxygen saturation (SaO2) time series present intermittent high-frequency high-amplitude oximetry patterns (IHHOP), which correlate with observed sleep-associated breathing disturbances. A new method for identifying such intermittent patterns is proposed. The method is based on the analysis of recurrence in the time series through the quantification of an optimal recurrence threshold (ϵopt). New time series for the value of ϵopt were constructed using a rolling window scheme, which allowed for real-time identification of the occurrence of IHHOPs. The results for the optimal recurrence threshold were confronted with standard metrics used in studies of obstructive sleep apnea, namely the oxygen desaturation index (ODI) and oxygen desaturation density (ODD). A high correlation between ϵopt and the ODD was observed. Using the value of the ODI as a surrogate to the apnea–hypopnea index (AHI), it was shown that the value of ϵopt distinguishes occurrences of sleep apnea with great accuracy. When subjected to binary classifiers, this newly proposed metric has great power for predicting the occurrences of sleep apnea-related events, as can be seen by the larger than 0.90 AUC observed in the ROC curve. Therefore, the optimal threshold ϵopt from recurrence analysis can be used as a metric to quantify the occurrence of abnormal behaviors in the arterial oxygen saturation time series.
... Similar parameters are also calculated for recovery events. Note that ABOSA also calculates other parameters not presented in this Screening of sleep apnea [29] , worsening of hypoxic load over time [14] , daytime sleepiness [11 , 27] DesSev (%-point) i DesAre a i TS T second Worsening of hypoxic load over time [13 , 14] , impaired vigilance [10] , daytime sleepiness [11 , 27] , elevated cardiac troponin I [28] , cardiovascular disease-related mortality ¶ [9] , incident heart failure ¶ [15] DesSev100 (%-point) i DesArea 100 i TS T second Cardiovascular disease mortality ¶ [30] DesDur (%-point) i DesDu r i TS T second × 100% Worsening of hypoxic load over time [13 , 14] , elevated cardiac troponin I [28] , mortality [21] Average desaturation duration (s) i DesDu r i n desaturation Worsening of hypoxic load over time [13] , daytime sleepiness [27] , differences in patients with similar sleep apnea severity [8] , differences between breathing cessation severities [31] Average desaturation depth (%) i DesDept h i n desaturation Impaired vigilance [10] , daytime sleepiness [27] , differences in patients with similar sleep apnea severity [8] , differences between breathing cessation severities [31] Average desaturation area (s%) i DesAre a i n desaturation ...
Background and objective
Many sleep recording software used in clinical settings have some tools to automatically analyze the blood oxygen saturation (SpO2) signal by detecting desaturations. However, these tools are often inadequate for scientific research as they do not provide SpO2 signal-based parameters which are superior in the estimation of sleep apnea severity and related medical consequences. In addition, these software require expensive licenses and they lack batch analysis tools. Thus, we developed the first freely available automatic blood oxygen saturation analysis software (ABOSA) that provides sophisticated SpO2 signal-based parameters and enables batch analysis of large datasets.
Methods
ABOSA was programmed with MATLAB. ABOSA automatically detects desaturation and recovery events from the SpO2 signals (EDF files) and calculates numerous parameters, such as oxygen desaturation index (ODI) and desaturation severity (DesSev). The accuracy of the ABOSA software was evaluated by comparing its desaturation scorings to manual scorings in Kuopio (n = 1981) and Loewenstein (n = 930) sleep apnea patient datasets. Validation was performed in a second-by-second manner by calculating Matthew's correlation coefficients (MCC) and median differences in parameter values. Finally, the performance of the ABOSA software was compared to two commercial software, Noxturnal and Profusion, in 100 patient subpopulations. As Noxturnal or Profusion does not calculate novel desaturation parameters, these were calculated with custom-made functions.
Results
The agreements between ABOSA and manual scorings were great in both Kuopio (MCC = 0.801) and Loewenstein (MCC = 0.898) datasets. However, ABOSA slightly overestimated the desaturation parameter values. The median differences in ODIs were 0.8 (Kuopio) and 0.0 (Loewenstein) events/h. Similarly, the median differences in DesSevs were 0.02 (Kuopio) and 0.01 (Loewenstein) percentage points. In a second-by-second analysis, ABOSA performed very similarly to Noxturnal and Profusion software in both Kuopio (MCCABOSA = 0.807, MCCNoxturnal = 0.807, MCCProfusion = 0.811) and Loewenstein (MCCABOSA = 0.904, MCCNoxturnal = 0.911, MCCProfusion = 0.871) datasets. Based on Noxturnal and Profusion scorings, the desaturation parameter values were similarly overestimated compared to ABOSA.
Conclusions
ABOSA is an accurate and freely available software that calculates both traditional clinical parameters and novel parameters, provides a detailed characterization of desaturation and recovery events, and enables batch analysis of large datasets. These are features that no other software currently provides making ABOSA uniquely suitable for scientific research use.
... The mean cumulative duration of oxyhemoglobin desaturation less than 80% during the postoperative nights in patients with cardiovascular complications was longer than in those without. Overnight or nocturnal oximetry is a valid tool in screening surgical patients for OSA using the oxygen desaturation index (ODI) [9][10][11]. Furthermore, hypoxemia detected by oximetry has been shown to predict postoperative cardiovascular events in surgical patients with OSA [12]. ...
Surgical patients with obstructive sleep apnea (OSA) have increased risk of perioperative complications. The primary objective is to determine the characteristics of surgical patients with unrecognized OSA requiring oxygen therapy for postoperative hypoxemia. The secondary objective is to investigate the characteristics of patients who were responsive to oxygen therapy. This was a post-hoc multicenter study involving patients with cardiovascular risk factors undergoing major non-cardiac surgery. Patients ≥45 years old underwent Type 3 sleep apnea testing and nocturnal oximetry preoperatively. Responders to oxygen therapy were defined as individuals with ≥50% reduction in oxygen desaturation index (ODI) on postoperative night 1 versus preoperative ODI. In total, 624 out of 823 patients with unrecognized OSA required oxygen therapy. These were mostly males, had larger neck circumferences, higher Revised Cardiac Risk Indices, higher STOP-Bang scores, and higher ASA physical status, undergoing intraperitoneal or vascular surgery. Multivariable regression analysis showed that the preoperative longer cumulative time SpO2 < 90% or CT90% (adjusted p = 0.03), and lower average overnight SpO2 (adjusted p < 0.001), were independently associated with patients requiring oxygen therapy. Seventy percent of patients were responders to oxygen therapy with ≥50% ODI reduction. Preoperative ODI (19.0 ± 12.9 vs. 14.1 ± 11.4 events/h, p < 0.001), CT90% (42.3 ± 66.2 vs. 31.1 ± 57.0 min, p = 0.038), and CT80% (7.1 ± 22.6 vs. 3.6 ± 8.7 min, p = 0.007) were significantly higher in the responder than the non-responder. Patients with unrecognized OSA requiring postoperative oxygen therapy were males with larger neck circumferences and higher STOP-Bang scores. Those responding to oxygen therapy were likely to have severe OSA and worse preoperative nocturnal hypoxemia. Preoperative overnight oximetry parameters may help in stratifying patients.
... En effet, la PSG est l'examen de choix pour étudier le sommeil. On peut également recourir en alternative à la polygraphie ventilatoire (PV) et accessoirement à la saturométrie nocturne (20)(21)(22). En comparaison aux rapports de la littérature africaine sur le SAHOS en lien avec la connaissance de la PSG, nos résultats sont supérieurs à ceux observés par Marijon en 2005 sur l'Ile de la réunion (23) (29)(30)(31). Elle est indiquée en première intention dans le SAHOS sévère, mais aussi dans le SAHOS à niveau de sévérité léger à modéré en présence d'une comorbidité grave. ...
Context and objective. Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a frequent pathology. The objective was to assess the knowledge as well as the diagnostic and therapeutic habits of general practitioners (GPs) concerning the OSAHS. Methods. A cross-sectional, observational study was conducted among GPs using an anonymous questionnaire that did not specify the purpose of the study beforehand. Results. Out of 177 GPs who answered the questionnaire, almost 70 % had graduated after 2009. University education had been the main source of information. The majority of GPs in the survey (62%) were not familiar with OSAHS. Cardinal symptoms of OSAHS (snoring, nocturnal apnea, daytime sleepiness) had been cited by more than half of GPs but without giving them any real significance in their medical practice. Half of them had never discussed the diagnosis of OSAHS with their patients. Obesity was widely cited as a factor associated with OSAHS by 68% of GPs, however other factors were either unrecognized or barely mentioned. More than half of GPs (54.2%) did not know the repercussions and complications of night apnea on the individual and his environment. Polysomnography as a key examination for OSAHS was cited by 56% of GPs. The existence of care was also indicated by a large number of them (87%) but without knowing the terms. Conclusion. OSAHS is a pathology affecting the population of Kinshasa, but little integrated into professional medical practices. Its cardinal symptoms, complications and diagnostic and therapeutic modalities are little known to GPs. This situation calls for further training of doctors through university education and continuing medical education. Contexte et objectif. Le syndrome d'apnées hypopnées obstructives du sommeil (SAHOS) est une pathologie fréquente, mais méconnue. L’objectif de cette enquête était d’évaluer les connaissances ainsi que les habitudes diagnostique et thérapeutique des médecins généralistes (MG) vis-à-vis le SAHOS. Méthodes. Etude transversale, déclarative, observationnelle menée auprès des MG de la ville de Kinshasa, à partir d’un questionnaire anonyme n’ayant pas précisé au préalable l’objet de l’étude. Les réponses aux questions et le nombre des répondants sont exprimés en fréquence et en pourcentage. Résultats. Sur 177 MG ayant répondu au questionnaire, près de 70% avaient obtenu leur diplôme après l’année 2009. Le cursus universitaire avait été la principale source d’information. La majorité des MG de l'enquête (62%) n'était pas familiarisée avec le SAHOS. Les symptômes cardinaux (ronflements, apnées nocturnes, somnolence diurne) avaient été cités par plus de moitié des MG mais sans leur donner de signification réelle dans leur pratique médicale. L’obésité a été largement citée comme un facteur associé au SAHOS par 68 % de MG, cependant les autres facteurs ont été méconnus ou à peine cités. Plus de la moitié des MG (54,2 %) ne connaissait pas les répercussions et les complications des apnées nocturnes sur l'individu et son environnement. La polysomnographie comme examen clé du SAHOS avait été citée par 56 % des MG. Le niveau des connaissances révélé par l’ensemble des résultats s’est avéré globalement faible. Conclusion. Le SAHOS est une pathologie fréquente, méconnue et très peu intégrée dans les pratiques professionnelles médicales à Kinshasa. Cette situation appelle un approfondissement de la formation des médecins par l’enseignement universitaire et la formation médicale continue.
... OSA can induce the onset of various comorbidities with an increase in the mortality rate. Sleep apnea causes sleep fragmentation and chronic intermittent hypoxia; the frequency and severity of apneas/hypopneas are measured with the apneahypopnea index (AHI) while the level of desaturation is measured with the oxygen desaturation index (ODI) [17,18]. The presence of OSA with a high AHI and a severe ODI induces a decline in testosterone levels (particularly in middle-aged men), an altered pituitary-gonadal axis, with evidence of sexual dysfunction [19]. ...
Obstructive sleep apnea (OSA) causes multiple local and systemic pathophysiological consequences, which lead to an increase in morbidity and mortality in patients suffering from this disorder. OSA presents with various nocturnal events of apnoeas or hypopneas and with sub-clinical airflow limitations during wakefulness. OSA involves a large percentage of the population, particularly men, but the estimate of OSA patients could be much broader than data from the literature. Most of the research carried out in the muscle field is to understand the causes of the presence of chronic nocturnal desaturation and focus on the genioglossus muscle and other muscles related to dilating the upper airways. Sparse research has been published regarding the diaphragm muscle, which is the main muscle structure to insufflate air into the airways. The article reviews the functional anatomy of the muscles used to open the upper respiratory tract and the non-physiological adaptation that follows in the presence of OSA, as well as the functional anatomy and pathological adaptive aspects of the diaphragm muscle. The intent of the text is to highlight the disparity of clinical interest between the dilator muscles and the diaphragm, trying to stimulate a broader approach to patient evaluation.
... AHI was defined as the per hour counts of apnea and hypopnea (Kapur et al., 2017). ODI was defined as the number of times per hour when oxygen saturation decreased, and the desaturation episodes referred to at least 3 % decrease in saturation (Rashid et al., 2021;Shen et al., 2018). The gold standard for diagnosis of adult OSA in general population was categorized through the AHI value as none (<5), mild (5-14.9), ...
Background
No previous study has explored the association of residential greenness with obstructive sleep apnoea (OSA) indexes.
Objective
To investigate the association of exposure to residential greenness with OSA indexes in adults in Guangdong Province, Southern China.
Methods
From January 1, 2005 to December 31, 2015, a total of 3925 participants were recruited from the Sleep Center of Guangdong Provincial People's Hospital. Apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) were measured by polysomnography or home sleep test (HST). Participants' daytime sleepiness scores were evaluated using The Epworth Sleeping Scale (ESS). The normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) were used to assess residential greenness levels. Generalized linear regression models were used to assess the associations of residential greenness with OSA indexes after adjusting for multiple covariates.
Results
The mean (standard deviation) age of the participants was 63.3 (14.4) years. In adjusted models, an interquartile range (IQR) increase in 3-year average NDVI was significantly associated with 9.8 % (95 % confidence interval [95 % CI]: 17.5 %, 2.1 %); 14.5 % (95 % CI: 24.5 %, 4.4 %) and 6.9 % (95 % CI: 13.7 %, 0.0 %) decreases in AHI, ODI and ESS scores, respectively. Furthermore, an IQR increase in 3-year average EVI was significantly associated with 7.8 % (95 % CI: 13.7 %, 1.9 %); 10.8 % (95 % CI: 18.3 %, 3.2 %) and 7.2 % (95 % CI: 12.5 %, 2.0 %) declines in AHI, ODI and ESS scores, respectively. Significant associations were only observed among males, adults aged ≥65 years old, and in the warm season.
Conclusions
Our study indicates that higher residential greenness was significantly associated with lower OSA indexes in adult population in South China, especially in males, in the elderly, and in the warm season.
... According to this review, a diagnosis of OSAS should be consid-ered with a 4% ODI of ≥ 15 events/hour; further evaluation is instead required with a 4% ODI ≥ 10 events/hour. Screening is recommended for the detection of OSAS associated with cardiovascular risk in middle-aged men without comorbidities 17 . In fact, untreated OSAS, in addition to causing depressive symptoms and reduced quality of social, economic and family life, can cause sudden death, uncontrolled hypertension, coronary heart disease and congestive heart failure 18 . ...
Objective:
This study reports our experience in a selected cohort of patients affected by mild-moderate OSAS, without tonsillar obstruction, and treated with pharyngoplasty.
Methods:
In a case-control retrospective study, we compared modified expansion sphincter pharyngoplasty (MESP) to modified barbed reposition pharyngoplasty (MBRP) in adult patients with oropharyngeal transversal collapse with a BMI ≤ 30 kg/m2, and mild-moderate obstructive sleep apnoea syndrome (OSAS). A clinical evaluation, including collection of anthropometric data and sleep endoscopy, was performed. Six months after surgery, symptoms recording, clinical evaluation and polysomnography (PSG) were repeated.
Results:
We enrolled 20 patients: 10 treated with MESP and 10 treated with MBRP. Mean apnoea-hypoapnoea index (AHI) was 22.8 (± 5.63). We observed in both groups a significant reduction of AHI and oropharyngeal obstruction (p = 0.01), with a success rate, according with Sher's criteria, of 90% for MESP and 80% for MBRP, respectively. Post-surgical pain and snoring reduction were significantly lower with MBRP.
Conclusions:
We recorded similar success rates for both techniques. MBRP may be considered better than MESP due to less surgical time, no potential mucosal damage, absence of knots, and faster recovery with less pain.
Introduction
Obstructive sleep apnoea (OSA) is characterised by blood oxygen desaturations and sleep disruptions manifesting undesirable consequences. Existing treatments including oral appliances, positive airway pressure (PAP) therapy and surgically altering the anatomy of the pharynx have drawbacks including poor long-term adherence or often involving irreversible, invasive procedures. Bilateral hypoglossal nerve stimulation (HNS BL ) is a new treatment for managing OSA, and this study is intended to determine whether an HNS BL system is a safe and effective treatment option for adults with OSA.
Methods and analysis
This is a pivotal, multicentre, prospective, single-arm study of HNS BL in PAP-intolerant adults with moderate to severe OSA. The device is activated 2 months after implantation with stimulation settings optimised before the final 12-month sleep study. At 12 months, the two coprimary effectiveness endpoints are the percentage of responders based on reduction in the Apnoea-Hypoponea Index, with hypopnoeas associated with 4% oxyhaemoglobin desaturation, and the Oxygen Desaturation Index, using drops in oxygen concentration >4% from baseline (ODI4). Secondary effectiveness endpoints include mean changes in quality-of-life assessments (daytime sleepiness and its effect on activities of daily living, OSA-specific quality of life, daytime sleepiness), levels of intermittent hypoxia, change in hypoxaemic burden and OSA severity.
Ethics and dissemination
The Food and Drug Administration, Advarra Institutional Review Board (IRB), University of Tennessee HSC IRB, University of Pennsylvania IRB, Weill Cornell Medicine IRB, Medical College of Wisconsin/Froedert Hospital, Human Research Protections Programme Vanderbilt University, St. Vincent’s Hospital Melbourne Human Research Ethics Committee, Ethisch Comite Universitair Ziekenhuis Antwerpen and Technische Universitat Munchen reviewed and approved this protocol. Study results will be disseminated through journal publications, updates to ClinicalTrials.gov and the Nyxoah website, and presentations at meetings and conferences.
Trial registration number
NCT03868618 .
Objectivo:
avaliar os resultados da cirurgia nasal isolada no tratamento da Síndrome da Apneia Obstrutiva do Sono (SAOS), através do impacto na redução do índice de Apneia-Hipopneia (IAH), do índice de dessaturação de oxigénio (ODI), da saturação periférica oxigénio mínima (SpO2min) e dos resultados da escala de sonolência de Epworth (ESE).
Desenho do Estudo:
estudo coorte retrospetivo
Material e métodos:
Foram consultados os processos clínicos dos doentes com diagnóstico de SAOS, que realizaram avaliação com estudo poligráfico do sono, estudo endoscópico da via aérea superior sob indução farmacológica do sono - Drug Induced Sleep Endoscopy (DISE) e Tomografia Computorizada (TC) de seios perinasais e faringe. Foram selecionados aqueles submetidos a cirurgia nasal como procedimento isolado com objetivo terapêutico e que realizaram estudo poligráfico do sono de controlo após a mesma. Pré e pós-operatoriamente, foram analisadas as seguintes variáveis: IAH, ODI, SpO2min, resultado da ESE e peso.
Resultados:
Foram incluídos 15 doentes, maioritariamente do sexo masculino (13/86,6%). Após a cirurgia, verificou-se uma melhoria estatisticamente significativa do IAH (p=0.019), do ODI (p=0,008) e da ESE (p=0,015). Não se verificou associação estatisticamente significativa entre a SpO2min (p=0,089) e o peso antes e após a cirurgia (p=0.862).
Conclusões:
A cirurgia nasal pode ser tratamento eficaz na SAOS, em doentes adequadamente selecionados.
Recently, numerous new diagnostic possibilities based on technical innovations have emerged in sleep medicine, especially in the field of sleep-disordered breathing. This article highlights selected new diagnostic approaches as well as technical advancements of already established methods, with which sleep physicians are already confronted in their clinical practice.
The article discusses alternative approaches based on reduced systems compared with current standard diagnostics. These include systems that are based on a reduced number of recording channels compared to current standard diagnostics, such as peripheral pulse oximetry or cardiopulmonary coupling, but also wearable devices (wearables) and smartphone applications as well as diagnostics using ambulatory electroencephalographic derivation.
Furthermore, alternatives to the established out- and inpatient recordings are available, among others based on peripheral arterial tonometry. Innovative approaches are shown in the field of radar-based systems for contactless monitoring of sleep, as well as the use of artificial intelligence, such as for acoustic analysis of breathing sounds during sleep.
Overall, these technologies represent promising advancements in sleep medicine that have the potential to improve the diagnosis and monitoring of sleep disorders. In particular, the ability to longitudinally record multiple nights in the home setting could compensate for reduced precision in the recording of biological parameters. However, only a small number of these methods has been sufficiently validated to date; furthermore, for the majority of these procedures, there is still no possibility for reimbursement under the German statutory health insurance.
Study objectives:
While heart failure with preserved ejection fraction (HFpEF) is associated with the presence of obstructive sleep apnea (OSA), few studies have examined the association between scoring systems used to predict HFpEF risk, such as the H2FPEF and HFA-PEFF scores, and OSA prevalence and severity.
Methods:
We performed chart review on all patients who underwent both an echocardiogram and sleep study at the University of Pennsylvania between July 1, 2020, and June 30, 2022. There were 277 patients in the final cohort after excluding patients with relevant comorbidities. . Associations between echocardiographic parameters and OSA severity, as well as between H2FPEF score and OSA severity, were examined using linear tests of trend. The association between H2FPEF score and prevalent OSA was examined with logistic regression.
Results:
OSA severity was associated with echocardiographic markers including left atrial volume index (p = 0.03) and left ventricular relative thickness (p = 0.008). Patients with high H2FPEF risk scores had over 17-fold higher odds of prevalent OSA compared to those with low-risk scores (17.7, 95% CI 4.3, 120.7, p < 0.001). Higher H2FPEF scores were strongly correlated with OSA severity (p < 0.001). After controlling for BMI, H2FPEF Scores were not associated with prevalence or severity of OSA.
Conclusions:
In an ambulatory population referred for sleep study and echocardiogram, markers of diastolic dysfunction were associated with OSA severity. OSA prevalence and severity were associated with increased H2FPEF scores, though these associations were largely explained by obesity. Clinicians should have low thresholds for referring OSA patients for cardiac workup and HFpEF patients for sleep study.
Obstructive sleep apnoea (OSA) is a sleep disorder with repetitive collapse of the upper airway during sleep, which leads to intermittent hypoxic events overnight, adverse neurocognitive, metabolic complications, and ultimately an increased risk of cardiovascular disease (CVD). The standard diagnostic parameter for OSA, apnoea–hypopnoea index (AHI), is inadequate to predict CVD morbidity and mortality, because it focuses only on the frequency of apnoea and hypopnoea events, and fails to reveal other physiological information for the prediction of CVD events. Novel parameters have been introduced to compensate for the deficiencies of AHI. However, the calculation methods and criteria for these parameters are unclear, hindering their use in cross-study analysis and studies. This review aims to discuss novel parameters for predicting CVD events from oximetry signals and to summarise the corresponding computational methods.
Obstructive sleep apnea (OSA) is a sleep disorder that has been associated with the incidence of other pathologies. Diagnosis is mainly based on the apnea–hypopnea index (AHI) obviating other repercussions such as intermittent hypoxemia, which has been found to be associated to cardiovascular complications. Blood‐based samples and urine have been the most utilised biofluids in metabolomics studies related to OSA, while sweat could be an alternative due to its non‐invasive and accessible sampling, its reduced complexity, and comparability with other biofluids. Therefore, this research aimed to evaluate metabolic overnight changes in sweat collected from patients with OSA classified according to the AHI and oxygen desaturation index (ODI), looking for potential cardiovascular repercussions. Pre‐ and post‐sleeping sweat samples from all individuals ( n = 61) were analysed by gas chromatography coupled to high‐resolution mass spectrometry after appropriate sample preparation to detect as many metabolites as possible. Permanent significant alterations in the sweat were reported for pyruvate, serine, lactose, and hydroxybutyrate. The most relevant overnight metabolic alterations in sweat were reported for lactose, succinate, urea, and oxoproline, which presented significantly different effects on factors such as the AHI and ODI for OSA severity classification. Overall metabolic alterations mainly affected energy production‐related processes, nitrogen metabolism, and oxidative stress. In conclusion, this research demonstrated the applicability of sweat for evaluation of OSA diagnosis and severity supported by the detected metabolic changes during sleep.
Objective:
To compare the efficacy of maxillomandibular advancement (MMA) for patients with obstructive sleep apnea (OSA) with class 2 versus 3 dentofacial deformities (DFDs).
Study design:
Retrospective chart review.
Setting:
Tertiary sleep surgery center.
Methods:
Patients with OSA and DFD class 2 versus 3 undergoing MMA at Stanford Sleep Surgery between 2014 and 2021 were matched by preoperative body mass index (BMI), age, and sex. Postoperative outcome was compared with polysomnography measures and patient-reported outcome measures (PROMs).
Results:
Twenty-eight matched subjects, 14 in each deformity group were identified and assessed. The mean age (standard deviation) was 34.29 (10.21) and 33.86 (10.23) for classes 2 and 3, respectively. The apnea-hypopnea index (AHI) decreased from 43.42 (28.30) to 9.6 (5.29) (p < .001) and 37.17 (35.77) to 11.81 (15.74) (p = .042) in class 2 and 3 subjects, respectively. The oxygen desaturation index (ODI) changed from 30.48 (24.02) to 6.88 (3.39) (p = .024) and 11.43 (11.40) to 5.44 (7.96) (p = .85) in class 2 and 3 subjects, respectively. The Epworth sleepiness scale changed from 8.93 (5.28) to 3.91 (2.70) (p = .018) and 10.23 (4.38) to 4.22 (3.07) (p = .006) in class 2 and 3 subjects, respectively.
Conclusion:
Among age, sex, and BMI-matched subjects, MMA is equally effective in both dentofacial class 2 and 3 groups, both objectively and subjectively. Preoperatively, dentofacial class 2 patients with OSA presented with the more severe disease with higher AHI and ODI. Dentofacial class 3 patients with OSA may require additional attention to improve nasal function outcomes.
Background and Objectives Obstructive sleep apnea (OSA) is associated with various health risks, including hypertension, cerebrovascular disease, myocardial infarction, diabetes, cognitive impairment, and all-cause mortality. While overnight polysomnography (PSG) is the gold standard for diagnosing OSA, it is costly and time-consuming. The STOP-Bang questionnaire is a convenient tool for OSA screening, but its high sensitivity comes at the expense of low specificity. The purpose of this study was to investigate the usefulness of combining the STOP-Bang questionnaire and a smartwatch capable of measuring oxygen saturation in screening for OSA.Subjects and Method Of the patients scheduled for PSG due to OSA, 109 patients voluntarily participated in the study by filling out a STOP-Bang questionnaire during their first visit and wearing a smartwatch during PSG.Results There were 80 males and 29 females, with the patients’ mean age of 45±13.3 years. Based on the apnea-hypopnea index (AHI), 19 patients (17.4%) were normal, 28 (25.7%) had mild OSA, 23 (21.1%) had moderate OSA, and 39 (35.8%) had severe OSA. When using the AHI threshold of AHI ≥15/h, the STOP-Bang alone showed sensitivity of 85.5% and specificity of 61.7%. Combining the STOP-Bang questionnaire with a smartwatch resulted in a slight decrease in sensitivity and a significant increase in specificity, yielding the values of 80.5% and 84.4%, respectively.Conclusion A two-step approach using the STOP-Bang and a smartwatch was implemented to enhance the diagnostic accuracy of screening OSA.
As the importance of good sleep continues to gain public recognition, the market for sleep-monitoring devices continues to grow. Modern technology has shifted from simple sleep tracking to a more granular sleep health assessment. We examine the available functionalities of consumer wearable sleep trackers (CWSTs) and how they perform in healthy individuals and disease states. Additionally, the continuum of sleep technology from consumer-grade to medical-grade is detailed. As this trend invariably grows, we urge professional societies to develop guidelines encompassing the practical clinical use of CWSTs and how best to incorporate them into patient care plans.
Purpose:
The aims of current meta-analysis was to combine data and statistics on the global prevalence of OSA and related factors in older adults.
Design:
A systematic review and meta-analysis.
Methods:
To find related studies, various databases were searched including Embase, PubMed, Scopus, Web of Science (WoS), MagIran, and SID (two local databases) using appropriate keywords, MeSH and controlled vocabulary, with no time limitation up to June, 2021. Heterogeneity of studies was evaluated using I2, and Egger's regression intercept was used to detect publication bias.
Findings:
39 studies with a total sample size of 33,353 people were included. The pooled prevalence of OSA in older adults was 35.9% (95% confidence interval: 28.7%-43.8%; I2 = 98.81%). Considering the high heterogeneity of included studies, subgroup analysis was conducted and yielded the most prevalent in Asia continent with 37.0% (95% CI: 22.4%-54.5%; I2 = 97.32%). However, heterogeneity was remained at high level. In the majority of studies, OSA was significantly and positively related to obesity, increased BMI, age, cardiovascular diseases, diabetes, and daytime sleepiness.
Conclusions:
Results of this study showed that global prevalence of OSA in older adults is high and is significantly related to obesity, increased BMI, age, cardiovascular diseases, diabetes, and daytime sleepiness. These findings can be used by experts working on the diagnosis and management of OSA in the geriatric population. These findings can be used by experts on the diagnosis and treatment of OSA in the older adults. Due to high heterogeneity, findings should be interpreted with great caution.
Objectives/Background
Interest in using blood oxygen desaturations in the diagnostics of sleep apnea has risen in recent years. However, no standardized criteria for desaturation scoring exist which complicates the drawing of solid conclusions from literature.
Patients/methods
We investigated how different desaturation scoring criteria affect the severity of nocturnal hypoxic load and the prediction of impaired daytime vigilance in 845 patients. Desaturations were scored based on three features: 1) minimum oxygen saturation drop during the event (2–20%, 1% interval), 2) minimum duration of the event (2–20s, 1s interval), and 3) maximum plateau duration within the event (5–60s, 5s interval), resulting in 4332 different scoring criteria. The hypoxic load was described with oxygen desaturation index (ODI), desaturation severity (DesSev), and desaturation duration (DesDur) parameters. Association between hypoxic load and impaired vigilance was investigated with covariate-adjusted area under curve (AUC) analyses by dividing patients into normal (≤5 lapses) and impaired (≥36 lapses) vigilance groups based on psychomotor vigilance test performance.
Results
The severity of hypoxic load varied greatly between different scoring criteria. For example, median ODI ranged between 0.4 and 12.9 events/h, DesSev 0.01–0.23 %-point, and DesDur 0.3–9.6 %-point when the minimum transient drop criterion of 3% was used and other two features were altered. Overall, the minimum transient drop criterion had the largest effect on parameter values. All models with differently determined parameters predicted impaired vigilance moderately (AUC = 0.722–0.734).
Conclusions
Desaturation scoring criteria greatly affected the severity of hypoxic load. However, the difference in the prediction of impaired vigilance between different criteria was rather small.
Background:
Evaluation and interpretation of the literature on obstructive sleep apnea is needed to consolidate and summarize key factors important for clinical management of the OSA adult patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).
Methods:
Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.
Results:
The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA and treatment on the multiple comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.
Conclusion:
This review of the literature in OSA consolidates the available knowledge and identifies the limitations of the current evidence. This effort aims to highlight the basis of OSA evidence-based practice and identify future research needs. Knowledge gaps and opportunities for improvement include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy. This article is protected by copyright. All rights reserved.
Objectives
To characterize and evaluate the estimation of oxygen saturation measured by a wrist-worn reflectance pulse oximeter during sleep.
Methods
Ninety-seven adults with sleep disturbances were enrolled. Oxygen saturation was simultaneously measured using a reflectance pulse oximeter (Galaxy Watch 4 [GW4], Samsung, South Korea) and a transmittance pulse oximeter (polysomnography) as a reference. The performance of the device was evaluated using the root mean squared error (RMSE) and coverage rate. Additionally, GW4-derived oxygen desaturation index (ODI) was compared with the apnea-hypopnea index (AHI) derived from polysomnography.
Results
The GW4 had an overall RMSE of 2.3% and negligible bias of -0.2%. A Bland-Altman density plot showed good agreement between the GW4 and the reference pulse oximeter. RMSEs were 1.65 ± 0.57%, 1.76 ± 0.65%, 1.93 ± 0.54%, and 2.93 ± 1.71% for normal (n = 18), mild (n = 21), moderate (n = 23), and severe obstructive sleep apnea (n = 35), respectively. The data rejection rate was 26.5%, which was caused by fluctuations in contact pressure and the discarding of data less than 70% of saturation. A GW4-ODI ≥5/h had the highest ability to predict AHI ≥15/h with sensitivity, specificity, accuracy, and area under the curve of 89.7%, 64.1%, 79.4%, and 0.908, respectively.
Conclusions
This study evaluated the estimation of oxygen saturation by the GW4 during sleep. This device complies with both Food and Drug Administration and International Organization for Standardization standards. Further improvements in the algorithms of wearable devices are required to obtain more accurate and reliable information about oxygen saturation measurements.
Obstructive sleep apnea hypoventilation syndrome (OSAHS) is a common sleep breathing disorder closely associated with cardiovascular disease. However, the respiratory sleep and related cardiovascular parameters on the apnea and hypopnea index (AHI) and life quality of primary snoring are unclear. We launched a cohort study focused on the association between respiratory sleep and cardiovascular-related parameters and apnea and hypopnea index, incorporating data from 218 patients with primary snoring in our medical center between Jun 1, 2015, and Apr 1, 2016. Thirty patients from Sichuan Cancer Hospital were used for validation. Patients with longer apnea time were more likely to progress to higher AHI (> 30) than controls (OR = 5.66, 95% CI = [2.79, 11.97], p < 0.001). Similarly, if patients have a higher value of diastolic blood pressure, they will also have a higher AHI (> 30) (HR [95% CI] = 3.42 [1.14, 13.65], p = 0.043). According to multivariate analysis, longest apnea time, the mean percentage of SaO2, and neckline length were independent risk factors of overall survival. A predictive model developed based on these factors above yielded a favorable agreement (C-index = 0.872) on the calibration curve. Thirty patients conducted external validation from Sichuan Cancer Hospital, displaying an AUC of 0.833 (0.782–0.884). Increased diastolic blood pressure and apnea time affect AHI level. An AHI prediction model based on these factors above can help clinicians predict the risk of high AHI events.
Background:
Polysomnography (PSG) is currently the "gold standard" for the diagnosis of the sleep apnoea hypopnoea syndrome (SAHS). Nocturnal oximetry (NO) has been used with contradictory results. A prospective study was performed to determine the accuracy of NO as a diagnostic tool and to evaluate the reduction in the number of PSGs if the diagnosis of SAHS had been established by this method.
Methods:
Two hundred and seventy five patients with a clinical suspicion of SAHS were admitted to undergo, in the same night, full PSG and NO. Desaturation was defined as a fall in the haemoglobin saturation level (SaO(2)) to lower than 4% from the baseline level and an oxygen desaturation index per hour (ODI) was obtained in each patient with three cut off points: >/= 5 (ODI-5), >/= 10 (ODI-10), and >/= 15 (ODI-15).
Results:
SAHS was diagnosed in 216 patients (194 men). After withdrawing patients with abnormal lung function (forced expiratory volume in one second (FEV(1)) lower than 80% predicted), sensitivity (SE), specificity (SP), positive and negative predictive values (PPV and NPV) of NO were: ODI-5 (80%, 89%, 97%, 48%); ODI-10 (71%, 93%, 97%, 42%); ODI-15 (63%, 96%, 99%, 38%). The accuracy for each ODI was 0.81, 0.75, and 0.70, respectively. If NO had been considered as a diagnostic tool and PSG had been performed only in patients with a negative NO (false negative and true negative) and those with a positive NO and abnormal pulmonary function tests, 135/275 (ODI-5), 156/275 (ODI-10), and 170/275 (ODI-15) PSGs would have been performed, a reduction of 140, 119, and 105, respectively.
Conclusion:
Nocturnal oximetry in patients with suspected SAHS and normal spirometric values permits the institution of therapeutic measures in most patients.
Obstructive sleep apnoea syndrome (OSAS) is a disorder that leads to metabolic abnormalities and increased cardiovascular risk. The aim of this study was to identify early laboratory markers of cardiovascular disease through analysis of oxidative stress in normal subjects and patients with OSAS. A prospective study was designed to compare outcomes of oxidative stress laboratory tests in 20 adult patients with OSAS and a control group of 20 normal subjects. Laboratory techniques for detecting and quantifying free radical damage must be targeted to assess the pro-oxidant component and the antioxidant in order to obtain an overall picture of oxidative balance. No statistical differences in age, sex distribution, or BMI were found between the two groups (p>0.05). There were significant differences in the apnoea/hypopnoea index (AHI) between OSAS patients and the control group (p<0.05). Statistically significant differences in isoprostane, advanced oxidation protein products (AOPP) and non-protein bound iron (NPBI) levels were found between the study and control groups. No significant difference in the levels of thiol biomarkers was found between the two groups. The main finding of the present study was increased production of oxidative stress biomarkers in OSAS patients. The major difference between thiols and other oxidative stress biomarkers is that thiols are antioxidants, while the others are expressions of oxidative damage. The findings of the present study indicate that biomarkers of oxidative stress in OSAS may be used as a marker of upper airway obstructive episodes due to mechanical trauma, as well as a marker of hypoxaemia causing local oropharyngeal inflammation.
Background:
Diagnosing obstructive sleep apnea (OSA) is clinically relevant because untreated OSA has been associated with increased morbidity and mortality. The STOP-Bang questionnaire is a validated screening tool for OSA. We conducted a systematic review and meta-analysis to determine the effectiveness of STOP-Bang for screening patients suspected of having OSA and to predict its accuracy in determining the severity of OSA in the different populations.
Methods:
A search of the literature databases was performed. Inclusion criteria were: 1) Studies that used STOP-Bang questionnaire as a screening tool for OSA in adult subjects (>18 years); 2) The accuracy of the STOP-Bang questionnaire was validated by polysomnography-the gold standard for diagnosing OSA; 3) OSA was clearly defined as apnea/hypopnea index (AHI) or respiratory disturbance index (RDI) ≥ 5; 4) Publications in the English language. The quality of the studies were explicitly described and coded according to the Cochrane Methods group on the screening and diagnostic tests.
Results:
Seventeen studies including 9,206 patients met criteria for the systematic review. In the sleep clinic population, the sensitivity was 90%, 94% and 96% to detect any OSA (AHI ≥ 5), moderate-to-severe OSA (AHI ≥15), and severe OSA (AHI ≥30) respectively. The corresponding NPV was 46%, 75% and 90%. A similar trend was found in the surgical population. In the sleep clinic population, the probability of severe OSA with a STOP-Bang score of 3 was 25%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability rose proportionally to 35%, 45%, 55% and 75%, respectively. In the surgical population, the probability of severe OSA with a STOP-Bang score of 3 was 15%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability increased to 25%, 35%, 45% and 65%, respectively.
Conclusion:
This meta-analysis confirms the high performance of the STOP-Bang questionnaire in the sleep clinic and surgical population for screening of OSA. The higher the STOP-Bang score, the greater is the probability of moderate-to-severe OSA.
Study objective:
To characterize the association among apnea-hypopnea indices (AHIs) determined using three common metrics for defining hypopnea, and to develop a model to calibrate between these AHIs.
Design:
Cross-sectional analysis of Sleep Heart Health Study Data.
Setting:
Community-based.
Participants:
There were 6,441 men and women age 40 y or older.
Measurement and results:
Three separate AHIs have been calculated, using all apneas (defined as a decrease in airflow greater than 90% from baseline for ≥ 10 sec) plus hypopneas (defined as a decrease in airflow or chest wall or abdominal excursion greater than 30% from baseline, but not meeting apnea definitions) associated with either: (1) a 4% or greater fall in oxyhemoglobin saturation - AHI4; (2) a 3% or greater fall in oxyhemoglobin saturation - AHI3; or (3) a 3% or greater fall in oxyhemoglobin saturation or an event-related arousal - AHI3a. Median values were 5.4, 9.7, and 13.4 for AHI4, AHI3, and AHI3a, respectively (P < 0.0001). Penalized spline regression models were used to compare AHI values across the three metrics and to calculate prediction intervals. Comparison of regression models demonstrates divergence in AHI scores among the three methods at low AHI values and gradual convergence at higher levels of AHI.
Conclusions:
The three methods of scoring hypopneas yielded significantly different estimates of AHI, although the relative difference is reduced in severe disease. The regression models presented will enable clinicians and researchers to more appropriately compare AHI values obtained using differing metrics for hypopnea.
This study proposes a method of automatically classifying sleep apnea/hypopnea events based on sleep states and the severity of sleep-disordered breathing (SDB) using photoplethysmogram (PPG) and oxygen saturation (SpO2) signals acquired from a pulse oximeter. The PPG was used to classify sleep state, while the severity of SDB was estimated by detecting events of SpO2 oxygen desaturation. Furthermore, we classified sleep apnea/hypopnea events by applying different categorisations according to the severity of SDB based on a support vector machine. The classification results showed sensitivity performances and positivity predictive values of 74.2% and 87.5% for apnea, 87.5% and 63.4% for hypopnea, and 92.4% and 92.8% for apnea + hypopnea, respectively. These results represent better or comparable outcomes compared to those of previous studies. In addition, our classification method reliably detected sleep apnea/hypopnea events in all patient groups without bias in particular patient groups when our algorithm was applied to a variety of patient groups. Therefore, this method has the potential to diagnose SDB more reliably and conveniently using a pulse oximeter.
Objectives In its guidelines on the use of portable monitors to diagnose obstructive sleep apnoea, the American Academy of Sleep Medicine endorses home polygraphy with type III devices recording at a minimum airflow the respiratory effort and pulse oximetry, but advises against simple pulse oximetry. However, oximetry is widely available and simple to use in the home. This study was designed to compare the ability of the oxygen desaturation index (ODI) based on oximetry alone with a stand-alone pulse oximeter (SPO) and from the oximetry channel of the ApneaLink Plus (ALP), with the respiratory disturbance index (RDI) based on four channels from the ALP to predict the apnoea–hypopnoea index (AHI) from laboratory polysomnography.
Design Cross-sectional diagnostic accuracy study.
Setting Sleep medicine practice of a multispecialty clinic.
Participants Patients referred for laboratory polysomnography with suspected sleep apnoea. We enrolled 135 participants with 123 attempting the home sleep testing and 73 having at least 4 hours of satisfactory data from SPO and ALP.
Interventions Participants had home testing performed simultaneously with both a SPO and an ALP. The 2 oximeter probes were worn on different fingers of the same hand. The ODI for the SPO was calculated using Profox software (ODISOX). For the ALP, RDI and ODI were calculated using both technician scoring (RDIMAN and ODIMAN) and the ALP computer scoring (RDIRAW and ODIRAW).
Results The receiver–operator characteristic areas under the curve for AHI ≥5 were RDIMAN 0.88 (95% confidence limits 0.81–0.96), RDIRAW 0.86 (0.76–0.94), ODIMAN 0.86 (0.77–0.95), ODIRAW 0.84 (0.75–0.93) and ODISOX 0.83 (0.73–0.93).
Conclusions We conclude that the RDI and the ODI, measured at home on the same night, give similar predictions of the laboratory AHI, measured on a different night. The differences between the two methods are small compared with the reported night-to-night variation of the AHI.
Aim: The aim of our study was to evaluate the sensitivity and specificity of Nocturnal Oximetry (NO) as a diagnostic screening tool for obstructive sleep apnoea hypopnoea syndrome (OSAHS), compared with polysomnography (PSG) as the gold standard. Methodology: 63 patients with clinical suspicion of OSAHS and exclusion of respiratory disease underwent PSG and NO. We then determined NO sensitivity, specificity, positive (PPV) and negative predictive values (NPV). Results: OSAHS was diagnosed in 47 patients with a mean age of 54 years. In the evaluation of the percentage of Total Sleep Time (TST) with oxygen desaturation below 90%, we found significant differences between patients with OSAHS (25.4 ± 29.7%) and without OSAHS (1 ± 1.5%), p
Polysomnography (PSG) is treated as the gold standard for diagnosing obstructive sleep apnea (OSA). However, it is labor-intensive, time-consuming, and expensive. This study evaluates validity of overnight pulse oximetry as a diagnostic tool for moderate to severe OSA patients.
A total of 699 patients with possible OSA were recruited for overnight oximetry and PSG examination at the Sleep Center of a University Hospital from Jan. 2004 to Dec. 2005. By excluding 23 patients with poor oximetry recording, poor EEG signals, or respiratory artifacts resulting in a total recording time less than 3 hours; 12 patients with total sleeping time (TST) less than 1 hour, possibly because of insomnia; and 48 patients whose ages less than 20 or more than 85 years old, data of 616 patients were used for further study. By further considering 76 patients with TST < 4 h, a group of 540 patients with TST ≥ 4 h was used to study the effect of insufficient sleeping time. Alice 4 PSG recorder (Respironics Inc., USA) was used to monitor patients with suspected OSA and to record their PSG data. After statistical analysis and feature selection, models built based on support vector machine (SVM) were then used to diagnose moderate and moderate to severe OSA patients with a threshold of AHI = 30 and AHI = 15, respectively.
The SVM models designed based on the oxyhemoglobin desaturation index (ODI) derived from oximetry measurements provided an accuracy of 90.42-90.55%, a sensitivity of 89.36-89.87%, a specificity of 91.08-93.05%, and an area under ROC curve (AUC) of 0.953-0.957 for the diagnosis of severe OSA patients; as well as achieved an accuracy of 87.33-87.77%, a sensitivity of 87.71-88.53%, a specificity of 86.38-86.56%, and an AUC of 0.921-0.924 for the diagnosis of moderate to severe OSA patients. The predictive outcome of ODI to diagnose severe OSA patients is better than to diagnose moderate to severe OSA patients.
Overnight pulse oximetry provides satisfactory diagnostic performance in detecting severe OSA patients. Home-styled oximetry may be a tool for severe OSA diagnosis.
Elevated loop gain, consequent to hypersensitive ventilatory control, is a primary nonanatomical cause of obstructive sleep apnoea (OSA) but it is not possible to quantify this in the clinic. Here we provide a novel method to estimate loop gain in OSA patients using routine clinical polysomnography alone. We use the concept that spontaneous ventilatory fluctuations due to apnoeas/hypopnoeas (disturbance) result in opposing changes in ventilatory drive (response) as determined by loop gain (response/disturbance). Fitting a simple ventilatory control model (including chemical and arousal contributions to ventilatory drive) to the ventilatory pattern of OSA reveals the underlying loop gain.
Following mathematical-model validation, we critically tested our method in patients with OSA by comparison with a standard (continuous positive airway pressure (CPAP) drop method), and by assessing its ability to detect the known reduction in loop gain with oxygen and acetazolamide.
Our method quantified loop gain from baseline polysomnography (correlation versus CPAP-estimated loop gain: n=28; r=0.63, p<0.001), detected the known reduction in loop gain with oxygen (n=11; mean± sem change in loop gain (ΔLG) −0.23±0.08, p=0.02) and acetazolamide (n=11; ΔLG −0.20±0.06, p=0.005), and predicted the OSA response to loop gain-lowering therapy.
We validated a means to quantify the ventilatory control contribution to OSA pathogenesis using clinical polysomnography, enabling identification of likely responders to therapies targeting ventilatory control.
Background
Obstructive sleep apnea (OSA) has been reported to be a risk factor for cardiovascular (CV) disease. Although the apnea-hypopnea index (AHI) is the most commonly used measure of OSA, other less well studied OSA-related variables may be more pathophysiologically relevant and offer better prediction. The objective of this study was to evaluate the relationship between OSA-related variables and risk of CV events.Methods and findingsA historical cohort study was conducted using clinical database and health administrative data. Adults referred for suspected OSA who underwent diagnostic polysomnography at the sleep laboratory at St Michael's Hospital (Toronto, Canada) between 1994 and 2010 were followed through provincial health administrative data (Ontario, Canada) until May 2011 to examine the occurrence of a composite outcome (myocardial infarction, stroke, congestive heart failure, revascularization procedures, or death from any cause). Cox regression models were used to investigate the association between baseline OSA-related variables and composite outcome controlling for traditional risk factors. The results were expressed as hazard ratios (HRs) and 95% CIs; for continuous variables, HRs compare the 75th and 25th percentiles. Over a median follow-up of 68 months, 1,172 (11.5%) of 10,149 participants experienced our composite outcome. In a fully adjusted model, other than AHI OSA-related variables were significant independent predictors: time spent with oxygen saturation
Purpose:
This study aims to assess the association between excessive daytime sleepiness (EDS) and variables extracted from the pulse-oximetry signal obtained during overnight polysomnography.
Methods:
A cross-sectional design was used to study the relation between four hypoxemia variables and EDS as determined by Epworth Sleepiness Scale scores (ESSS) in 200 consecutive patients, newly diagnosed with obstructive sleep apnea (OSA), as defined by an apnea-hypopnea index (AHI)≥ 15. Hypoxemia measurements were compared between sleepy (ESSS ≥ 10) and nonsleepy (ESSS<10) patients before and after dichotomizing the cohort for each hypoxemia variable (and for AHI) such that there were 35 (165) patients in each of the corresponding higher (lower) subcohorts. The hypoxemia variables were combined into a biomarker, and its accuracy for predicting sleepiness in individual patients was evaluated. We planned to interpret prediction accuracy above 80 % as evidence that hypoxemia predicted EDS.
Results:
Hypoxemia was unassociated with sleepiness in OSA patients with AHI in the range of 15 to 50. In patients with AHI>50, the hypoxemia biomarker (but not individual hypoxemia variables) predicted sleepiness with 82 % accuracy.
Conclusion:
Nocturnal hypoxemia as determined by a polyvariable biomarker reliably predicted EDS in patients with severe OSA (AHI>50), indicating that oxygen fluctuation had a direct role in the development of EDS in patients with severe OSA.
The definitions of respiratory events and recommendations concerning monitoring technology will continue to evolve as more knowledge is gained about the effect of using different definitions or technology on outcomes. Improved ability to predict patients who will improve symptomatically with treatment (especially in patients with "milder" obstructive sleep apnea) is clearly needed. It is hoped that this document is simply a starting point of a new process to provide a flexible and evolving set of respiratory definitions. The recommendations in this document are based predominantly on consensus. The task force attempted to carefully weigh the current evidence as well as to respond to concerns raised by the sleep community about the recommendations in the 2007 scoring manual. Many areas of uncertainty remain. No set of definitions can completely cover the wide variety of respiratory events encountered by clinicians. There is no substitute for clinical correlation of PSG findings with the clinical symptoms of the patient being evaluated.
Purpose
Newly developed algorithms putatively derive measures of sleep, wakefulness, and respiratory disturbance index (RDI) through detailed analysis of heart rate variability (HRV). Here, we establish levels of agreement for one such algorithm through comparative analysis of HRV-derived values of sleep–wake architecture and RDI with those calculated from manually scored polysomnographic (PSG) recordings.
Methods
Archived PSG data collected from 234 subjects who participated in a 3-day, 2-night study characterizing polysomnographic traits of chronic fatigue syndrome were scored manually. The electrocardiogram and pulse oximetry channels were scored separately with a novel scoring algorithm to derive values for wakefulness, sleep architecture, and RDI.
Results
Four hundred fifty-four whole-night PSG recordings were acquired, of which, 410 were technically acceptable. Comparative analyses demonstrated no difference for total minutes of sleep, wake, NREM, REM, nor sleep efficiency generated through manual scoring with those derived through HRV analyses. When NREM sleep was further partitioned into slow-wave sleep (stages 3–4) and light sleep (stages 1–2), values calculated through manual scoring differed significantly from those derived through HRV analyses. Levels of agreement between RDIs derived through the two methods revealed an R = 0.89. The Bland–Altman approach for determining levels of agreement between RDIs generated through manual scoring with those derived through HRV analysis revealed a mean difference of −0.7 ± 8.8 (mean ± two standard deviations).
Conclusion
We found no difference between values of wakefulness, sleep, NREM, REM sleep, and RDI calculated from manually scored PSG recordings with those derived through analyses of HRV.
Background:
It has been suggested that sleep-disordered breathing (SDB) is a risk factor for diabetes, but long-term follow-up studies are lacking. The aim of this community-based study was to analyze the influence of SDB on glucose metabolism after > 10 years.
Methods:
Men without diabetes (N = 141; mean age, 57.5 years) were investigated at baseline, including whole-night respiratory monitoring. After a mean period of 11 years and 4 months, they were followed up with an interview, anthropometric measurements, and blood sampling. Insulin resistance was quantified using the homeostasis model assessment of insulin resistance (HOMA-IR). ΔHOMA-IR was calculated as (HOMA-IR at follow-up − HOMA-IR at baseline). An oral glucose tolerance test was performed on 113 men to calculate the insulin sensitivity index.
Results:
The mean apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) at baseline were 4.7 and 3.3, respectively. At follow-up, 23 men had diabetes. An ODI > 5 was a predictor of developing diabetes (OR, 4.4; 95% CI, 1.1-18.1, after adjusting for age, BMI, and hypertension at baseline and ΔBMI and years with CPAP during follow-up). The ODI was inversely related to the insulin sensitivity index at follow-up (r = −0.27, P = .003). A deterioration in HOMA-IR was significantly related to all variables of SDB (AHI, AHI > 5; ODI, ODI > 5; minimum arterial oxygen saturation), even when adjusting for confounders. When excluding the variable years with CPAP from the multivariate model, all associations weakened.
Conclusions:
SDB is independently related to the development of insulin resistance and, thereby, the risk of manifest diabetes mellitus.
To quantify sources of night-to-night variability.
This project was conducted in 285 middle-aged African American, Caucasian, and Chinese women from the Study of Women's Health Across the Nation (SWAN) Sleep Study living in Chicago, the Detroit area, Oakland, and Pittsburgh. The study used 3 repeated nights of in-home polysomnography (PSG) measures. Night 1 data included assessment of sleep staging, sleep apnea, and periodic limb movements, while Nights 2 and 3 focused on sleep staging.
Mean total sleep time (TST) increased substantially from 365 minutes on Night 1 to 391 minutes and 380 minutes, respectively, on Nights 2 and 3. Mean percent sleep efficiency (SE%) for the 3 nights were 83%, 85%, and 85%, respectively. Night 1 sleep values were significantly different than Nights 2 and 3 measures except for S2 (%), S1 (min), and Delta (S3+4)%. Nights 2 and 3 differences in variability were negligible. Obesity, past smoking, and financial strain measures were associated with greater Night 1 vs. Night 2 or Night 3 differences. We concluded that there was significant Night 1 vs. Nights 2 and 3 variability and, though relatively modest, it was sufficient to bias estimates of association. Additionally, personal characteristics including smoking, obesity, and financial strain increased night-to-night variability.
This reports adds new information about between and within person sources of variation with in-home PSG and identifies elements that are essential in the design and planning of future sleep studies of multi-ethnic groups in social and physiological transition states such as the menopause.
In 2003, the QUADAS tool for systematic reviews of diagnostic accuracy studies was developed. Experience, anecdotal reports, and feedback suggested areas for improvement; therefore, QUADAS-2 was developed. This tool comprises 4 domains: patient selection, index test, reference standard, and flow and timing. Each domain is assessed in terms of risk of bias, and the first 3 domains are also assessed in terms of concerns regarding applicability. Signalling questions are included to help judge risk of bias. The QUADAS-2 tool is applied in 4 phases: summarize the review question, tailor the tool and produce review-specific guidance, construct a flow diagram for the primary study, and judge bias and applicability. This tool will allow for more transparent rating of bias and applicability of primary diagnostic accuracy studies.
One of the most important caveats of ambulatory devices is the inability to record and stage sleep. We assessed an algorithm determining 4 different stages: wake, light sleep, deep sleep, and REM sleep using signals derived from the portable monitor Watch-PAT100 (PAT recorder).
Participants (38 normal subjects and 189 patients with obstructive sleep apnea [OSA]) underwent simultaneous overnight recordings with polysomnography (PSG) and the PAT recorder in a study originally designed to assess the accuracy of the PAT recorder in diagnosing OSA. Light/deep sleep and REM sleep from the PAT recorder recording were automatically scored based on features extracted from time series of peripheral arterial tone amplitudes and inter pulse periods. The PSG scored sleep stages 1 and 2 were classified as light sleep for epoch-by-epoch comparisons.
The overall agreement in detecting light/deep and REM sleep were 88.6% ± 5.9% and 88.7% ± 5.5%, respectively. There was a good agreement between PSG and the PAT recorder in quantifying sleep efficiency (78.4% ± 9.9% vs. 78.8% ± 13.4%), REM latency (237 ± 148 vs. 225 ± 159 epochs), and REM percentage (14.4% ± 6.5% vs. 19.3% ± 8.7%). OSA severity did not affect the sensitivity and specificity of the algorithm. The Cohen κ coefficient for detecting all sleep stages: sleep from wake, REM from NREM sleep, and deep from light sleep were 0.48, 0.55, 0.59, and 0.46, respectively.
Analysis of autonomic signals from the PAT recorder can detect sleep stages with moderate agreement to more standard techniques in normal subjects and OSA patients. This novel algorithm may provide insights on sleep and sleep architecture when applying the PAT recorder for OSA diagnosis.
Obstructive sleep apnea (OSA) may lead to life-threatening problems if it is left undiagnosed. Polysomnography is the "gold standard" for OSA diagnosis; however, it is expensive and not widely available. The objective of this systematic review is to identify and evaluate the available questionnaires for screening OSA.
We carried out a literature search through MEDLINE, EMBASE, and CINAHL to identify eligible studies. The methodological validity of each study was assessed using the Cochrane Methods Group's guideline.
Ten studies (n = 1,484 patients) met the inclusion criteria. The Berlin questionnaire was the most common questionnaire (four studies) followed by the Wisconsin sleep questionnaire (two studies). Four studies were conducted exclusively on "sleep-disorder patients", and six studies were conducted on "patients without history of sleep disorders". For the first group, pooled sensitivity was 72.0% (95% confidence interval [CI]: 66.0-78.0%; I(2) = 23.0%) and pooled specificity was 61.0% (95% CI: 55.0-67.0%; I(2) = 43.8%). For the second group, pooled sensitivity was 77.0% (95% CI: 73.0-80.0%; I(2) = 78.1%) and pooled specificity was 53.0% (95% CI: 50-57%; I(2) = 88.8%). The risk of verification bias could not be eliminated in eight studies due to insufficient reporting. Studies on snoring, tiredness, observed apnea, and high blood pressure (STOP) and STOP including body mass index, age, neck circumference, gender (Bang) questionnaires had the highest methodological quality.
The existing evidence regarding the accuracy of OSA questionnaires is associated with promising but inconsistent results. This inconsistency could be due to studies with heterogeneous design (population, questionnaire type, validity). STOP and STOP-Bang questionnaires for screening of OSA in the surgical population are suggested due to their higher methodological quality and easy-to-use features.
To compare apnea-hypopnea indices (AHIs) derived using 3 standard hypopnea definitions published by the American Academy of Sleep Medicine (AASM); and to examine the impact of hypopnea definition differences on the measured prevalence of obstructive sleep apnea (OSA).
Retrospective review of previously scored in-laboratory polysomnography (PSG).
Two tertiary-hospital clinical sleep laboratories.
328 consecutive patients investigated for OSA during a 3-month period.
N/A.
AHIs were originally calculated using previous AASM hypopnea scoring criteria (AHI(Chicago)), requiring either >50% airflow reduction or a lesser airflow reduction with associated >3% oxygen desaturation or arousal. AHIs using the "recommended" (AHI(Rec)) and the "alternative" (AHI(Alt)) hypopnea definitions of the AASM Manual for Scoring of Sleep and Associated Events were then derived in separate passes of the previously scored data. In this process, hypopneas that did not satisfy the stricter hypopnea definition criteria were removed. For AHI(Rec), hypopneas were required to have > or =30% airflow reduction and > or =4% desaturation; and for AHI(Alt), hypopneas were required to have > or =50% airflow reduction and > or =3% desaturation or arousal. The median AHI(Rec) was approximately 30% of the median AHI(Chicago), whereas the median AHI(Alt), was approximately 60% of the AHI(Chicago), with large, AHI-dependent, patient-specific differences observed. Equivalent cut-points for AHI(Rec) and AHI(Alt), compared to AHI(Chicago) cut-points of 5, 15, and 30/h were established with receiver operator curves (ROC). These cut-points were also approximately 30% of AHI(Chicago) using AHI(Rec) and 60% of AHI(Chicago) using AHI(Alt). Failure to adjust cut-points for the new criteria would result in approximately 40% of patients previously classifled as positive for OSA using AHI(Chicago) being negative using AHI(Rec) and 25% being negative using AHI(Alt).
This study demonstrates that using different published standard hypopnea definitions leads to marked differences in AHI. These results provide insight to clinicians and researchers in interpreting results obtained using different published standard hypopnea definitions, and they suggest that consideration should be given to revising the current scoring recommendations to include a single standardized hypopnea definition.
When conducting a treatment intervention study, it is assumed that a level of reliability can be obtained from the measurement tool such that the outcome can be reasonably assessed.
Investigate the reliability of laboratory polysomnography, the gold standard for assessment of treatment outcomes for obstructive sleep apnea, at a 1-month interval.
In a clinical trial of 118 patients recruited to assess the effects of a pharmaceutical treatment intervention, a subset of 20 patients designated as placebo controls completed two polysomnography studies, one at baseline and one at least one month later.
The correlation between the overall Apnea/Hypopnea indices from the two polysomnography (PSG) studies was poor (r = 0.44) and the results were biased, with a mean increase of seven events per hour on night 2. Twenty-five percent of the subjects had an increase greater than 20 events/hour on night 2 and only 45% of participants had a night-to-night difference of < or =5 events/hour. The correlation between overall apnea indexes for nights 1 and 2 (r = 0.61) was improved, compared to the overall apnea/hypopnea indexes. The correlation in sleep efficiency across the two nights was relatively week (r = 0.52) but significant. The correlations between nights 1 and 2 for the percentage of time supine (r = 0.70) and the supine apnea-hypopnea index (AHI) (r = 0.69) were similar and highly significant. The correlation for the non-supine AHI was only 0.25
In this study, the reliability of a single-night PSG in measuring treatment outcome was compromised as a result of the large night-to-night variability of subjects' obstructive sleep apnea (OSA). Studies employing the AHI as an outcome need to be adequately powered with respect to the inherent night-to-night variability in the measurement. When assessing treatment intervention outcomes, there may be benefit from the acquisition and averaging of multiple nights of data in order to mitigate the inherent night-to-night variability of OSA and improve the accuracy of the outcome assessment.
To comprehensively evaluate the ability and reliability of the representative previously proposed oxyhemoglobin indexes derived automatically for predicting the severity of obstructive sleep apnea hypopnea syndrome (OSAHS).
Patients with a diagnosis of OSAHS by standard polysomnography were recruited from China Medical University Hospital Centre. There were 257 patients in the learning set and 279 patients in the validation set. The presence of OSAHS was defined as apnea-hypopnea index (AHI) > 5/h. Three kinds of oxyhemoglobin indexes, including the oxyhemoglobin desaturation index (ODI), time-domain index, and frequency-domain index, were used. Degrees of severity were AHI > 15/h and AHI > 30/h, representing moderate and severe OSAHS. A total of 28 oxyhemoglobin indexes were tested in our study.
Among the three kinds of indexes, ODI had a better diagnostic performance than the time-domain and frequency-domain indexes, with the results coincident in the validation set and learning set. For predicting the severity of OSAHS with AHI > 15/h or > 30/h, the ODI clinically had the higher correlation with AHI than time-domain and frequency-domain indexes, with sensitivity/specificity achieving 84.0%/84.3% in AHI > 15/h and 87.8%/96.6% in AHI > 30/h, respectively.
Based on the smaller SEE of the AHI, the ODI had a significantly smaller SEE than the time-domain and frequency-domain indexes. The ODI index provided a high level of diagnostic sensitivity and specificity at different degrees of OSAHS severity.
We examined the effects of arousal- and desaturation-based scoring criteria on the apnea-hypopnea index (AHI) and on the measured prevalence of obstructive sleep apnea (OSA). Ninety-four randomly selected patients underwent overnight polysomnography. Studies were scored according to three different criteria for hypopnea, as defined by a >= 10 s discernible reduction in thoracoabdominal movement associated with: (1) >= 4% decrease in oxygen saturation (SaO2) (Type A); (2) either a >= 4% decrease in SaO2 or an arousal (Type B); or (3) electroencephalographically based arousal alone (Type C). Excellent correlation existed between AHI-A, AHI-B, and the oxygen desaturation index (ODI) (r > 0.98). AHI-A and AHI-B differed by only 2.04 +/- 1.72/h (2 SD). AHI-A and AHI-B differed from the ODI by 1.04 +/- 4.07/h and 3.07 +/- 4.30/h, respectively. Despite these small differences, use of the Type B rather than Type A definition resulted in an extra case of OSA being diagnosed for every 14 to 31 patients tested, depending on the definition of OSA (AHI: >= 5, 10, 15, or 20/h). The addition of arousal-based scoring criteria for hypopnea causes only small changes in the AHI, but if OSA is defined solely by an AHI value, the measured prevalence of OSA will increase.
Using spectral analysis of oximetry data, we prospectively evaluated the validity of this methodology in patients clinically suspected of suffering from obstructive sleep apnoea (OSA). A total of 233 outpatients were studied. Nocturnal oximetry was performed simultaneously with conventional polysomnography for all participants. The power density of oxygen saturation was analysed using Fast-Fourier transformation of the oximetric signal. Nocturnal oximetry test results were considered as abnormal (suspicion of OSA) if a peak in the spectrum between the period boundaries 30 and 70 s was observed. A normal test result was defined as the absence of the 30-70 s peak from the spectrum. Single-blind evaluation was performed by three independent observers, and agreement of two or more of these was considered definitive. The peak amplitude and the ratio of the area enclosed in the 30-70 s peak to the total area of the spectrum (r(S)) were measured. The presence of a peak has a sensitivity of 78%, a specificity of 89%, a positive predictive value of 89% and a negative predictive value of 78%. Apnoea-hypopnoea indexes were correlated significantly with peak amplitude (r=0.74; P<0.001) and with r(S) (r=0.69; P<0.001). For a peak amplitude threshold of 0.7%(2), the sensitivity was 94% and the specificity was 65% for OSA diagnosis. Using a threshold for r(S) of 0.15, the sensitivity was 91% and the specificity was 67%. Thus the spectral analysis of nocturnal oximetry and identification of a peak at 30-70 s could be useful as a diagnostic technique for OSA subjects.