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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
... OSA is characterized by repeated episodes of total or partial upper airway collapse obstructing air ow. These episodes result in intermittent nocturnal hypoxemia or cyclical episodes of desaturation and re-oxygenation [17]. ODI indicates the number of times that oxygen saturation decreases per hour, regardless of the duration [17]. ...
... These episodes result in intermittent nocturnal hypoxemia or cyclical episodes of desaturation and re-oxygenation [17]. ODI indicates the number of times that oxygen saturation decreases per hour, regardless of the duration [17]. ...
... COPD and obesity are in ammatory diseases and both predispose individuals to OSA. Intermittent hypoxemia is comparable to ischemia-reperfusion injury, leading to oxidative stress and contributing to reactive oxygen species and in ammatory mediator production, which triggers upper airway and systemic in ammation [17]. ...
Purpose The rates of chronic obstructive pulmonary disease (COPD) and obesity are increasing worldwide. Both COPD and obesity are highly associated with obstructive sleep apnea (OSA) and all three conditions are associated with reduced quality of life. Liraglutide is a glucagon-like peptide 1 receptor agonist (GLP-1 RA) approved for weight loss and the treatment of type 2 diabetes mellitus. In addition, liraglutide has anti-inflammatory properties. We investigated the effect of treatment with liraglutide on health-related quality of life (HRQoL) and OSA in people with obesity and COPD. Methods
We designed and performed a double-blinded randomized controlled trial of obese participants with COPD from two outpatient clinics. Forty patients were randomized to a liraglutide group (3.0 mg, subcutaneous) and a placebo group, to receive treatment for 40 weeks. At baseline and the end of the medication period, the participants underwent cardiorespiratory monitoring and completed Short Form-36 version 2 (SF-36v2) and Epworth Sleepiness Scale (ESS).ResultsWe diagnosed 84% of the participants with some degree of OSA. Compared to placebo, liraglutide resulted in reductions in Apnea–Hypopnea Index (AHI), Oxygen Desaturation Index (ODI) and a rise in Epworth Sleepiness Scale (ESS) in certain OSA subgroups and improved several SF-36v2 domains. ConclusionOSA is common among obese people with COPD. 40 weeks of treatment with liraglutide may improve some measures of OSA and HRQoL in obese people with COPD. Trial registrationStudy procedures were in accordance with the Declaration of Helsinki after approval by the Scientific Ethics Committee of The Region of Southern Denmark (j. no S-20170147) and Eudract (j. no. 2017-003551-32). The study was registered at clinicaltrials.gov (NCT03466021) and monitored according to Good Clinical Practice (GCP) by the GCP Unit of Odense University Hospital (Odense, Denmark).
... However, portable monitors (PM) for PSG type III can be used at home (5) at a much more affordable cost (6). In addition, other confounding factors exist in the diagnosis of OSA; these include the positional component, body mass index (BMI), sex, age, and associated comorbidities (7)(8)(9). ...
... As OSA is a disease with a high prevalence (1,25) and is still largely unknown to the general population, it is assumed that simpler diagnostic methods, which can be offered to a large part of the population, can provide advantageous results (7,9). In Brazil, the rate of OSA underdiagnosis is high and that the Brazilian public unified health system has diagnosed OSA in only 0.07% of the population (25). ...
... The use of oximetry has been extensively investigated in the last decade as an auxiliary method in OSA diagnosis by expanding access to diagnosis, thereby improving the quality of life of more vulnerable populations (24,25). The results of this study, as well as the existing literature (7)(8)(9)(10)(11)(12)(13)(14)(15)(16)19,21,(25)(26)(27)(28)(29)(30), indicate that, greater the degree of apnea, greater the chances of correct diagnosis based on ODI. A recent systematic review (7) demonstrates the methodological heterogeneity with respect to the following: criterion for ODI (3% and 4%), cut-off point for the classification of the degree of apnea, and the different statistical methods used. ...
Objectives:
Owing to the fact that obstructive sleep apnea (OSA) is an underreported disease, the strategy used for the diagnosis of OSA has been extensively dissected to devise a simplified process that can be accessed by the public health services. Polysomnography (PSG) type I, the gold standard for the diagnosis of OSA, is expensive and difficult to access by low-income populations. In this study, we aimed to verify the accuracy of the oxyhemoglobin desaturation index (ODI) in comparison to the apnea-hypopnea index (AHI) using a portable monitor.
Methods:
We evaluated 94 type III PSG home test results of 65 elderly patients (69.21±6.94 years old), along with information, such as the body mass index (BMI) and sex, using data obtained from a clinical trial database.
Results:
A significant linear positive correlation (r=0.93, p<0.05) was observed between ODI and AHI, without any interference from sex, BMI, and positional component. The sensitivity of ODI compared to that of AHI increased with an increase in the severity of OSA, while the specificity of ODI in comparison to that of AHI was high for all degrees of severity. The accuracy of ODI was 80.7% for distinguishing between patients with mild and moderate apnea and 84.4% for distinguishing between patients with moderate and severe apnea.
Conclusion:
The ODI values obtained in uncontrolled conditions exhibited high sensitivity for identifying severe apnea compared to the AHI values, and correctly identified the severity of OSA in more than 80% of the cases. Thus, oximetry is promising strategy for diagnosing OSA.
... 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.
... The presence of mild OSA may have clinical significance. An ODI greater than 5 events/hour is a predictor of developing type-2 diabetes after adjusting for confounding variables in a community-based sample (Rashid et al., 2021). Also, hypoxia with oxyhemoglobin saturation < 90% for > 9 minutes is a stronger predictor of cardiovascular events over AHI (Drager et al., 2007;Drager et al., 2009;Rashid et al., 2021;Kapur et al., 1999). ...
... An ODI greater than 5 events/hour is a predictor of developing type-2 diabetes after adjusting for confounding variables in a community-based sample (Rashid et al., 2021). Also, hypoxia with oxyhemoglobin saturation < 90% for > 9 minutes is a stronger predictor of cardiovascular events over AHI (Drager et al., 2007;Drager et al., 2009;Rashid et al., 2021;Kapur et al., 1999). Both findings suggest the clinical relevance of measuring these parameters in the general population. ...
Objective: This prospective and cross-sectional study investigated the occurrence of obstructive sleep apnea (OSA) and related symptoms in medical students. Method: Sociodemographic and anthropometric data were collected. The survey included the Epworth sleepiness scale, Berlin questionnaire, STOP-Bang, and NoSAS. Participants underwent overnight digital monitoring of respiratory events (≥ 3% drop in SpO2) using a high-resolution oximeter. Those with high risk for OSA in the Berlin questionnaire or an oxygen desaturation index ≥ 5 to < 15 events/hour, were examined through type 3 polysomnography. Results: The evaluated sample comprised 64 students, aged 22.3±2.3 years, and 38 (59.4%) males. A high risk for OSA frequency was detected in 10.9% of the sample through the Berlin questionnaire, and in 4.7% through STOP-Bang and NoSAS. A mild form of this disorder was diagnosed in 4.7% of the sample through type 4 polysomnography, and in 6.2% using type 3 polysomnography. Excessive daytime sleepiness and being overweight were associated with the occurrence of mild obstructive sleep apnea (p ≤0.05). Males presented higher body mass index values, neck circumference, oxygen desaturation index events/hour, and continuous values in the Berlin questionnaire, STOP-Bang, and NoSAS, than females (p ≤0.05). Conclusion: Despite a low occurrence of the assessed sleep-disordered breathing among medical students, male gender, overweight and sleepiness consisted of factors associated with obstructive sleep apnea, indicating that medical students with this profile should be early and systematically screened for this condition.
... Based on the ODI, patients were divided into three groups: mild (5)(6)(7)(8)(9)(10)(11)(12)(13)(14), moderate (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29), and severe (≥30). Patients with an ODI < 5 ...
... Intermittent chronic hypoxemia is a risk factor for serious complications related to OSAS, such as neurocognitive deterioration. 23 It causes inflammation, oxidative stress, endothelial dysfunction, and increased sympathetic activation, contributing to multi-organ comorbidities. 24 Recurrent episodes of hypoxia-reoxygenation are associated with high levels of pro-inflammatory markers, including tryptophan and kynurenine. ...
Objectives
This study aimed to compare serum levels of brain-derived neurotrophic factor (BDNF) and neurofilament light (NfL) chain in normal individuals and patients with mild and moderate-severe obstructive sleep apnea syndrome (OSAS).
Methods
We enrolled 81 subjects referred to Otorhinolaryngology (Ear-Nose-Throat), Gazi University Faculty of Medicine, between 2017 and 2019. Based on the severity of OSAS, patients were divided into three groups: group 1 with mild OSAS (apnea-hypopnea index [AHI] 5-15; n = 26), group 2 with moderate-severe OSAS (AHI > 15; n = 32), and group 3 with normal individuals (AHI scores < 5; n = 23).
Results
Serum NfL and BDNF levels were evaluated together with the clinical data for all subjects. Significant differences were seen in the oxygen desaturation index (ODI), apnea index, hypopnea index, sleep efficiency, and NfL levels (P < .05) between the three groups. In the moderate-severe group, NfL levels showed a significant positive correlation with apnea index (P < .05, r = .389), hypopnea index (P < .05, r = .455), and ODI (P = .04; r = .362).
Conclusions
Our findings clarify the pathophysiology of OSAS in cases of repetitive hypoxia and chronic neuronal damage. Based on our results, we recommend that in addition to BDNF, NfL should also be evaluated in different and larger patient cohorts.
... OSA has been shown to be associated with a variable degree of nasal inflammation, and uvular mucosal congestion and airway hyper-reactivity due to intermittent hypoxemia may trigger upper airway inflammation [2]. A recent study has reported unstable breathing during the phenomenon known as rapid-eye movement (REM) rebound, with changes in sleep status after induction of general anesthesia, and that patients with OSA present a particularly high perioperative airway risk [3]. Therefore, we should pay special attention to airway management in the presence of dentofacial deformity, from the viewpoint of OSA, during the early perioperative period of orthognathic surgery. ...
... Patients with skeletal class II malocclusion and mandibular hypoplasia have an increased risk of OSA due to anatomical constriction of the upper respiratory tract [2,4]. Although patients with skeletal class III malocclusion have a significantly larger pharyngeal airway space and a larger anterior-posterior dimension than patients with skeletal class II malocclusion [3,5], some cases of postoperative OSA have been reported after mandibular setback in patients with skeletal class III and without previous OSA symptoms [4][5][6][7]. Undiagnosed "silent" OSA in dentofacial deformity has been reported as well [8]. ...
Purpose
The incidence of obstructive sleep apnea (OSA) immediately after surgery in patients with dentofacial deformities without previous OSA remains unknown. We aimed to perioperatively evaluate factors associated with oxygen desaturation index (ODI) during sleep, 7 days after bilateral splitting ramus osteotomy (BSSRO) in patients without previous OSA.
Methods
Fifty-one patients (15 males, 36 females) with dentofacial deformities, scheduled to undergo BSSRO, were included. Polysomnography was performed before orthognathic surgery. Perioperative OSA was evaluated with peripheral arterial tonometry on the day of surgery and 1, 2, 3, 4, and 7 days postoperatively. Rapid eye movement (REM) sleep periods and the ODI were measured. Factors associated with perioperative ODI after surgery were statistically analyzed.
Results
REM sleep periods were significantly decreased on the day of surgery and significantly increased at 4 and 7 days postoperatively, compared to the preoperative period. ODI increased on the day of surgery, decreased after 1 day, and increased again at 4 and 7 days postoperatively. ODI on the day of surgery was significantly increased due to increased preoperative ODI, overjet, and SN-MP angle and decreased SNA and SNB angle. ODI at 7 days postoperatively was significantly increased due to increased REM sleep periods and decreased SN-MP and gonial angle. ODI was increased in response to REM sleep periods 7 days after BSSO.
Conclusion
Airway management in patients with dentofacial deformity should be given more attention by preoperative assessment for OSA, even in the absence of previous OSA, until 7 days postoperatively due to REM rebound.
... Oximetry has been validated to screen patients against apnea-hypopnea index (AHI) from lab-PSG and portable devices. These studies are mostly limited to sleep clinic patients from a single centre [9][10][11][12][13]. The predictive performance of the overnight oximetry is not known for at-risk surgical patients undergoing major non-cardiac surgery. ...
... Oximetry serves as a simple tool to identify these at-risk surgical patients to ensure optimal perioperative management. A recent systematic review on patients referred to sleep clinic also recommended using ODI �15 events per hour for predicting OSA but ODI �10 events per hour for further evaluation of OSA [9]. Although there has been a number of studies to predict OSA using oximetry [10,11,16,17], this is the first study to show that overnight pulse oximetry is a valid screening tool in predicting OSA in surgical patients with cardiovascular risk factors. ...
Introduction:
In adults with cardiovascular risk factors undergoing major noncardiac surgery, unrecognized obstructive sleep apnea (OSA) was associated with postoperative cardiovascular complications. There is a need for an easy and accessible home device in predicting sleep apnea. The objective of the study is to determine the predictive performance of the overnight pulse oximetry in predicting OSA in at-risk surgical patients.
Methods:
This was a planned post-hoc analysis of multicenter prospective cohort study involving 1,218 at-risk surgical patients without prior diagnosis of sleep apnea. All patients underwent home sleep apnea testing (ApneaLink Plus, ResMed) simultaneously with pulse oximetry (PULSOX-300i, Konica Minolta Sensing, Inc). The predictive performance of the 4% oxygen desaturation index (ODI) versus apnea-hypopnea index (AHI) were determined.
Results:
Of 1,218 patients, the mean age was 67.2 ± 9.2 years and body mass index (BMI) was 27.0 ± 5.3 kg/m2. The optimal cut-off for predicting moderate-to-severe and severe OSA was ODI ≥15 events/hour. For predicting moderate-to-severe OSA (AHI ≥15), the sensitivity and specificity of ODI ≥ 15 events per hour were 88.4% (95% confidence interval [CI], 85.7-90.6) and 95.4% (95% CI, 94.2-96.4). For severe OSA (AHI ≥30), the sensitivity and specificity were 97.2% (95% CI, 92.7-99.1) and 78.8% (95% CI, 78.2-79.0). The area under the curve (AUC) for moderate-to-severe and severe OSA was 0.983 (95% CI, 0.977-0.988) and 0.979 (95% CI, 0.97-0.909) respectively.
Discussion:
ODI from oximetry is sensitive and specific in predicting moderate-to-severe or severe OSA in at-risk surgical population. It provides an easy, accurate, and accessible tool for at-risk surgical patients with suspected OSA.
... The best cutoff for ODI to predict moderate-to-severe and severe sleep apnea was chosen by comparing the predictive parameters of 3 commonly used ODI cutoffs (ODI ≥5, ODI ≥10, and ODI ≥15 events/h) reported in the literature. 24,25 Sensitivity of at least 70% was considered adequate to maximize the predictive performance. High sensitivity was prioritized over specificity, because in clinical setting, it will enable identification of most patients with sleep apnea. ...
... However, the proposed ODI cutoff in this study is lower than the previous studies in surgical and sleep clinic populations, in which they recommended using ODI ≥10 events/h in predicting moderate-to-severe sleep apnea. 20,24,34 Compared to previous studies, our population is distinctly different as these patients have both central and OSA. We found that 59% had sleep apnea (AHI ≥5) (72% obstructive, 20% central, and 8% indeterminate sleep apnea) with a high prevalence of moderate (23%) and severe sleep apnea (31%), 7 whereas the other studies evaluated oximetry for isolated OSA. ...
Background:
Long-term use of opioids for treatment of chronic pain is associated with significant risks including worsening unrecognized or untreated sleep apnea that may increase morbidity and mortality. Overnight oximetry has been validated for predicting sleep apnea in surgical and sleep clinic patients. The objective of the study was to assess the predictive accuracy of oxygen desaturation index (ODI 4%) from home overnight oximetry when compared to apnea hypopnea index (AHI) from polysomnography for predicting sleep apnea in patients taking opioids for chronic pain.
Methods:
This was a planned post hoc analysis of a prospective cohort study conducted at 5 pain clinics. Patient characteristics and daily morphine milligram equivalent (MME) dose were recorded. All consented patients underwent home overnight oximetry (PULSOX-300i, Konica Minolta Sensing, Inc, Osaka, Japan) and in-laboratory polysomnography. The predictive performance of ODI 4% from oximetry was assessed against AHI from polysomnography.
Results:
Among 332 consented patients, 181 with polysomnography and overnight oximetry data were analyzed. The mean age and body mass index of 181 patients were 52 ± 13 years and 29 ± 6 kg/m2, respectively, with 40% men. The area under the receiver operating curve for ODI to predict moderate-to-severe sleep apnea (AHI ≥15 events/h) and severe sleep apnea (AHI ≥30 events/h) was 0.82 (95% confidence interval [CI], 0.75-0.88) and 0.87 (95% CI, 0.80-0.94). ODI ≥5 events/h had a sensitivity of 85% (95% CI, 74-92) and specificity of 57% (95% CI, 52-61) to predict moderate-to-severe sleep apnea. ODI ≥15 events/h had a sensitivity of 71% (95% CI, 55-83) and specificity of 88% (95% CI, 84-91) to predict severe sleep apnea.
Conclusions:
Overnight home oximetry has a high predictive performance in predicting moderate-to-severe and severe sleep apnea in patients on opioids for chronic pain. It is a useful additional tool for health care providers for the screening of sleep apnea in this high-risk group.
... 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.
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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)43 years), obese (BMI >37 kg/m2), 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.
... For example, Ulysses et al. [17] used time spent below a certain level saturation (TSA), the saturation variability index and other indicators to evaluate AHI, and compared the diagnostic performance of SA under different metrics. The oxygen desaturation index (ODI) is defined as the number of oxyhemoglobin desaturation below a certain threshold [18]. Ling et al. [19] found that the use of ODI improved the accuracy of moderate and severe OSA detection. ...
Sleep apnea (SA) is a common sleep disorder which could impair the human physiological system. Therefore, early diagnosis of SA is of great interest. The traditional method of diagnosing SA is an overnight polysomnography (PSG) evaluation. When PSG has limited availability, automatic SA screening with a fewer number of signals should be considered. The primary purpose of this study is to develop and evaluate a SA detection model based on electrocardiogram (ECG) and blood oxygen saturation (SpO2). We adopted a multimodal approach to fuse ECG and SpO2 signals at the feature level. Then, feature selection was conducted using the recursive feature elimination with cross-validation (RFECV) algorithm and random forest (RF) classifier used to discriminate between apnea and normal events. Experiments were conducted on the Apnea-ECG database. The introduced algorithm obtained an accuracy of 97.5%, a sensitivity of 95.9%, a specificity of 98.4% and an AUC of 0.992 in per-segment classification, and outperformed previous works. The results showed that ECG and SpO2 are complementary in detecting SA, and that the combination of ECG and SpO2 enhances the ability to diagnose SA. Therefore, the proposed method has the potential to be an alternative to conventional detection methods.
... However, it is known that in OSAS oxygen desaturations are more associated to drowsiness than AHI. 30 Patients with MS showed a worse sleep quality, in terms of duration, efficiency, and architecture compared to healthy subjects. As shown by Buratti et al, 31 the course of MS may be influenced by sleep quality, possibly because of the role of sleep in some oligodendrocyte functions, such as myelination. ...
Background:
Multiple sclerosis (MS) represents a risk factor for sleep disorders, but there are conflicting results about the prevalence and severity of sleep-related breathing disorders (SRBD) in MS. Most available data come from self-administered questionnaires.
Objective:
To conduct a polysomnographic study in MS focused on SRBD, compared to a group of healthy controls (HC), also considering the neuroimaging findings. To evaluate the impact of SRBD on vigilance, fatigue and depression in MS.
Methods:
In this cross-sectional, observational, instrumental study, 67 MS patients (men/women: 20/47; mean age: 50.6±8.2 years) underwent PSG and maintenance of wakefulness test. Findings were compared to 67 age-, sex-, BMI-matched HC, by using parametric (Student's t-test) and nonparametric statistics (chi-squared test). A subgroup analysis was then performed, evaluating the influence of brainstem (mesencephalic, pontine and medullary) lesions at neuroimaging on instrumental and clinical data: MS patients with at least one brainstem lesion vs MS patients without vs HC.
Results:
The frequency of SRBD was comparable in MS patients and HC. No MS patient had a central apnea index ≥2/h. The respiratory disturbance index (RDI) did not correlate to clinical parameters such as fatigue and depression. Patients with MS were drowsier than HC (47% vs 26%, p = 0.019) and showed a worse sleep pattern, in terms of duration, efficiency and architecture.
Conclusion:
Our study does not provide evidence of an association between MS-specific symptoms such as fatigue, sleepiness, depression and central or obstructive apneas, even in the presence of brainstem lesions.
... The other consequences of OSA are due to the alterations in gas exchange during sleep [14]. The oxygen saturation in OSA patients is lower than in healthy patients [15], which can lead to cardiovascular effects [16] in both the short or long term [17]. The most common cardiovascular effects related to OSA are hypertension [18], stroke [19], sudden and unexpected death [20], and arrhythmia [21]. ...
Objective:
The mandibular advancement device (MAD) is currently suggested in patients with mild to moderate obstructive sleep apnea (OSA). This study investigated the effects of a new fully customizable MAD-type device called, "It Makes You Sleep" (IMYS), in patients with mild to moderate OSA.
Methods:
Sixteen patients (14 men and 2 women; mean age 62; SD ± 11 years) were retrospectively enrolled. Each patient received home sleep apnea testing (HSAT) at baseline (T0) and after three months (T1) of IMYS treatment. The Apnea-Hypopnea Index (AHI), the Oxygen Desaturation Index (ODI), the Minimum Oxygen Saturation (minSO2) and the Medium Oxygen Saturation (medSO2) were analyzed.
Results:
From T0 to T1, the IMYS treatment showed a significant reduction of AHI and ODI and a significant increase of minSO2 and medSO2.
Conclusion:
The IMYS appliance is an effective device for treating mild or moderate OSA.
... ODI is defined as the number of events per hour with at least 4% decrease in saturation from the average saturation in the preceding 120 s for at least 10s [13]. The severity of sleep apnea was classified based on previously reported oxygen desaturation index (ODI) categorization (No OSA: ODI <5, mild: ≥5 to <15, moderate: ≥15 to <30, and severe OSA: ≥30 events per hour) [14]. ...
Study objective
Obstructive sleep apnea (OSA) is known to be associated with postoperative cardiovascular events in patients undergoing major non-cardiac surgery. The objective of the study is to determine whether preoperative oximetry-derived hypoxemia predicts postoperative cardiovascular events in surgical patients with unrecognized obstructive sleep apnea.
Design and setting
The study was a planned post hoc analyses of a multicenter prospective cohort study.
Patients
The inclusion criteria were patients ≥45 years old undergoing major non-cardiac surgery with cardiovascular risk factors.
Interventions and measurements
All patients underwent pre-operative pulse oximetry (PULSOX-300i, Konica-Minolta Sensing, Inc). The severity of OSA was classified based on oxygen desaturation index (ODI) (mild: ≥5 to <15, moderate: ≥15 to <30, and severe OSA: ≥30 events/h). The 30 days cardiovascular events were a composite of myocardial injury, cardiac death, congestive heart failure, thromboembolism, atrial fibrillation, and stroke.
Main results
For 1218 patients with mild, moderate, or severe OSA (mean age: 67.2 ± 9.3 years; body mass index: 27.0 ± 5.3 kg/m²), the rate of postoperative cardiovascular events was 16.4%, 25.2%, and 29.8% respectively. The multivariable analysis showed that preoperative oxygen desaturation index (ODI) ≥30 events per hour {adjusted hazard ratio (aHR) 1.63 [95% confidence interval (CI): 1.05–2.53]}, and cumulative time spent during sleep with oxygen saturation below 80% (CT80) ≥10 min {aHR 1.79 [95% CI: 1.28–2.50]} were independent predictors of 30-day postoperative cardiovascular events.
Conclusions
Preoperative ODI ≥30 events per hour and CT80 ≥ 10 min are associated with increased risk of postoperative cardiovascular events. Preoperative screening using oximetry helps in risk stratification for unrecognized sleep apnea.
Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT01494181
... The collapse of the upper airway during sleep is the hallmark of OSA and breathing is interrupted for at least 10 seconds [1,2]. Complete cessation of breathing is repeated many times during sleep, due to which the amount of oxygen in the blood decreases and several systems are adversely affected [3]. ...
... The other consequences of SRBD are due to the alterations in gas exchange during sleep [6]. The oxygen saturation in SRBD patients is lower than in healthy patients [7], and this factor can lead to cardiovascular effects in both the short and the long term [8]. The purpose of this Special Issue is to provide an overview of recent advances in SRBD monitoring and assessment, including: the design, development and application of advanced evaluation methods; and treatment based on cutting edge scientific knowledges. ...
The term “sleep-related breathing disorders” (SRDB) comprehends a spectrum of pathologic conditions characterized by abnormal respiration during sleep, that can affect both adults and growing subjects. The expanding knowledge on this topic has revealed that impaired sleeping and breathing have profound effects on many systemic functions, therefore a modern approach requires the collaboration of different professionals like the otorhinolaryngologist, pneumologist, neurologist, cardiologist, psychologist, dentist, and many others. The real prevalence of such conditions is unknown, especially in children, even though a growing awareness can be found among Governments, researchers, and public opinion, especially for the social implications that SRDB can have. Moreover, recent studies have raised attention on comorbidities that can be associated with SRDB, influencing each other. Regarding the current international situation, it would be interesting to evaluate the progress of COVID-19 disease in SRDB patients. Defining the state-of-the-art knowledge on all the conditions orbiting around SRDB, from all points of view—aetiology, diagnosis, clinical management, interdisciplinarity, public health management—would be of great interest and impact to improve future research and the quality of life of SRDB patients.
... In the past decade, oximetry has shown to have promising diagnostic validity in predicting sleep apnea. 26 In the general and bariatric populations, the addition of overnight oximetry with a screening questionnaire was shown to improve the diagnostic parameters for detecting sleep apnea. 17 18 27-29 Overnight oximetry using wearable pulse oximeters improve the convenience of monitoring patients' oxygen levels during sleep in their natural environment (ie, at home). ...
Background
There is an increased risk of sleep apnea in patients using opioids for chronic pain. We hypothesized that a simple model comprizing of: (1) STOP-Bang questionnaire and resting daytime oxyhemoglobin saturation (SpO 2 ); and (2) overnight oximetry will identify those at risk of moderate-to-severe sleep apnea in patients with chronic pain.
Method
Adults on opioids for chronic pain were recruited from pain clinics. Participants completed the STOP-Bang questionnaire, resting daytime SpO 2 , and in-laboratory polysomnography. Overnight oximetry was performed at home to derive the Oxygen Desaturation Index. A STOP-Bang score ≥3 or resting daytime SpO 2 ≤95% were used as thresholds for the first step, and for those identified at risk, overnight oximetry was used for further screening. The Oxygen Desaturation Index from overnight oximetry was validated against the Apnea-Hypopnea Index (≥15 events/hour) from polysomnography.
Results
Of 199 participants (52.5±12.8 years, 58% women), 159 (79.9%) had a STOP-Bang score ≥3 or resting SpO 2 ≤95% and entered the second step (overnight oximetry). Using an Oxygen Desaturation Index ≥5 events/hour, the model had a sensitivity of 86.4% and specificity of 52% for identifying moderate-to-severe sleep apnea. The number of participants who would require diagnostic sleep studies was decreased by 38% from Step 1 to Step 2 of the model.
Conclusion
A simple model using STOP-Bang questionnaire and resting daytime SpO 2 , followed by overnight oximetry, can identify those at high risk of moderate-to-severe sleep apnea in patients using opioids for chronic pain.
Trial registration number
NCT02513836 .
... Oxymetric measures can be extracted from pulse oximetry, including mean oxygen saturation, percentage of time with oxygen saturation < 90%, and oxygen desaturation index (ODI). A systematic review evaluated the diagnostic accuracy of ODI for SDB, significant heterogeneity exists among studies with sensitivities ranged from 32% to 98.5%, while specificities ranged from 47.7% to 98% (18). Furthermore, studies have revealed that hypoxemia, rather than AHI, were well associated with cardiovascular risk (19,20). ...
Background
Polysomnography (PSG) is the gold standard for diagnosis of sleep-disordered breathing (SDB). But it is impractical to perform PSG in all patients with diabetes. The objective was to develop a clinically easy-to-use prediction model to diagnosis SDB in patients with diabetes.
Methods
A total of 440 patients with diabetes were recruited and underwent overnight PSG at West China Hospital. Prediction algorithms were based on oxygen desaturation index (ODI) and other variables, including sex, age, body mass index, Epworth score, mean oxygen saturation, and total sleep time. Two phase approach was employed to derivate and validate the models.
Results
ODI was strongly correlated with apnea-hypopnea index (AHI) (r s = 0.941). In the derivation phase, the single cutoff model with ODI was selected, with area under the receiver operating characteristic curve (AUC) of 0.956 (95%CI 0.917–0.994), 0.962 (95%CI 0.943–0.981), and 0.976 (95%CI 0.956–0.996) for predicting AHI ≥5/h, ≥15/h, and ≥30/h, respectively. We identified the cutoff of ODI 5/h, 15/h, and 25/h, as having important predictive value for AHI ≥5/h, ≥15/h, and ≥30/h, respectively. In the validation phase, the AUC of ODI was 0.941 (95%CI 0.904–0.978), 0.969 (95%CI 0.969–0.991), and 0.949 (95%CI 0.915–0.983) for predicting AHI ≥5/h, ≥15/h, and ≥30/h, respectively. The sensitivity of ODI ≥5/h, ≥15/h, and ≥25/h was 92%, 90%, and 93%, respectively, while the specificity was 73%, 89%, and 85%, respectively.
Conclusions
ODI is a sensitive and specific tool to predict SDB in patients with diabetes.
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.
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
Air pollution may be a contributing risk factor for obstructive sleep apnea (OSA). However, the health effects of co-exposure to multiple air pollutants on OSA patients remain unclear.
Objectives
To assess the joint effect of multi-pollutants on sleep disordered breathing (SDB) parameters in patients with or without OSA and identify the dominant pollutants.
Methods
A total of 2524 outpatients from April 2020 to May 2021 were recruited in this cross-sectional study. Ambient air pollutants data were obtained from the nearest central monitoring stations to participant's residential address. SDB parameters were measured by the ApneaLink devices, including apnea-hypopnea index (AHI), hypopnea index (HI), oxygen desaturation index (ODI), average oxygen saturation (SpO2), percentage sleep time with <90% saturation (T90), and desaturation. Bayesian kernel machine regression (BKMR) was applied to evaluate the effects of multiple pollutants.
Results
Significant associations were observed between air pollutants and SDB parameters (including increases in AHI, HI, ODI, and desaturation) among patients with OSA. Co-exposure to air pollutants was positively correlated with AHI, HI, and ODI. PM10 and O3 dominated the effects of pollutants mixtures on OSA, with the highest posterior inclusion probabilities (PIP) values of 0.592 and 0.640, respectively. Stratified analysis showed that, compared to male patients with OSA, stronger effects on the SDB parameters were observed in female patients. Stronger associations were also found in the warm season than those in the cold season.
Conclusion
Co-exposure to air pollutants was associated with SDB parameters among patients with OSA, PM10 and O3 might play the dominant roles.
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 1,013 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/m ² ). 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 (AUC) - 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.
Objective:
Adenotonsillectomy is a recognised treatment for paediatric obstructive sleep apnoea. Recent literature highlights the need to assess outcomes in the extremely obese subpopulation. This study reviewed the efficacy of adenotonsillectomy performed in patients with extreme obesity.
Method:
A retrospective analysis of attendees at a tertiary paediatric obesity clinic was performed, identifying patients with a body mass index z-score equal to or more than three who had undergone adenotonsillectomy for obstructive sleep apnoea. Electronic patient records, including respiratory polygraphy, were analysed.
Results:
Nine patients met the study criteria. All required nocturnal non-invasive ventilation pre-operatively. Mean age at referral was 6.9 years, and average age of non-invasive ventilation commencement was 7.8 years. Post-operatively, 8 patients (89 per cent) required non-invasive ventilation with evidence of post-operative obstructive sleep apnoea.
Conclusion:
In extreme obesity, adenotonsillectomy does not prevent the need for non-invasive ventilation. Management of this patient group requires treatment of obesity alongside potential surgical intervention. Poor efficacy in treating obstructive sleep apnoea may influence the decision to proceed with adenotonsillectomy.
Background
Obstructive sleep apnea (OSA) is one of the common sleep-related breathing disorders in children. However, polysomnography (PSG) is an expensive and labor-intensive diagnostic modality that may not always be feasible, especially in low-income countries or in non-tertiary hospitals. Portable monitors (PMs), a new approach for OSA diagnosis, have become more widely used with lower intolerance and cost in recent years. We aimed to analyze the diagnostic performance of Level IV PMs compared with PSG for the diagnosis of pediatric OSA.
Methods
PubMed and Embase databases were searched for studies published in English up to December 31, 2020 evaluating the diagnostic accuracy of Level IV PMs against the apnea-hypopnea index (AHI) measured using overnight in-laboratory polysomnography (PSG) in children and adolescents. A random-effects bivariate model was used to estimate the summary sensitivity and specificity of oximetry-based statistical classifiers. A qualitative evaluation of studies was performed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) rating.
Results
In total, 20 studies involving 7,062 participants were included in this systematic review. Among these articles, 7 studies (oximetry based on new mathematical classifiers) involving 5,098 individuals satisfied the criteria for quantitative synthesis. Compared with AHI evaluation measured by PSG, different PM systems achieved diagnostic accuracy with variable degrees of success. A meta-analysis showed a pooled sensitivity of 74% (95% confidence interval [CI]: 66–80%) and pooled specificity of 90% (95% CI: 85–94%). The area under the summary receiver operating characteristic (SROC) curve was 0.89 (95% CI: 0.86–0.92).
Conclusion
This study showed the potential of Level IV PMs for screening pediatric OSA patients. Oximetry based on new mathematical classifiers may provide a simple and effective alternative to PSG in the diagnosis of pediatric OSA especially in the context of appropriate clinical evaluation.
Objective
This study aimed to evaluate nocturnal oximetry approaches in identifying obstructive sleep apnea (OSA) among bariatric surgical candidates.
Methods
This was a cross-sectional study involving adult bariatric patients who were undergoing in-lab polysomnography and who were previously screened with the GOAL questionnaire. OSA severity was established as any OSA, moderate/severe OSA, and severe OSA. Oximetry data were evaluated as oxygen saturation (average and nadir), oxygen desaturation index (ODI) at 3%, and proportion of time spent with oxygen saturation <90%. Associations between oximetry data and the apnea-hypopnea index (AHI) were assessed by Spearman correlation index (r), linear regression, logistic regression, and discrimination.
Results
All oximetry values were significantly correlated with the AHI among 1,178 individuals, with the ODI emerging as the better parameter (r = 0.911, p < 0.001). Using linear regression, the ODI was the only predictor of the AHI (β = 0.952, p < 0.001). In the multivariate analysis, the ODI was the only independent parameter predicting OSA at all severity levels. In addition, the ODI exhibited excellent discrimination to predict OSA and displayed improved performance among individuals screened as being at high risk versus those at low risk with the GOAL instrument.
Conclusions
The ODI emerges as a valid surrogate predictor of the AHI, particularly among those screened as being at high risk for OSA.
Turkish Thoracic Society Early Career Members Taskforce Group’s Virtual Congress Notes, Part I: ERS 2020 Virtual Congress
Available from: https://www.toraks.org.tr/site/community/downloads/tS5bMgnfB14Yh_5n
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.