Lia Rita Azeredo Bittencourt

Universidade Federal de São Paulo, San Paulo, São Paulo, Brazil

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Publications (152)347.61 Total impact

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    ABSTRACT: Objective Patients with craniocervical junction malformations (CCJM) tend to suffer more frequently from sleep respiratory disturbances, which are more frequent and severe in patients with basilar invagination. Here we evaluate if patients with CCJM and sleep respiratory disorders (SRD) present smaller airway dimensions than patients without SRD. Method Patients with CCCM with and without sleep respiratory disturbances were evaluated clinically by Bindal's score, modified Mallampati classification, full-night polysomnography and upper airway cone beam tomography. Results Eleven patients had sleep respiratory disorders (SRD), and nine patients performed control group without SRD. CCJM patients with SRD were predominantly female, older, had higher BMI, were more likely to have Mallampati grades 3 and 4 and had statistically significant smaller anteroposterior diameter of the upper airway than patients without SRD. Conclusion Patients with CCJM and sleep respiratory disturbances have higher BMI, higher Mallampati score and smaller anterior posterior diameter of the upper airway.
    Arquivos de Neuro-Psiquiatria 05/2015; 73(4). DOI:10.1590/0004-282X20150008
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    ABSTRACT: The sleep of patients admitted to coronary care unit (CCU) may be compromised. A feasible and cost-effective tool to evaluate sleep in this scenario could provide important data. The aim of this study was to evaluate sleep with a questionnaire developed specifically for the CCU and to validate it with polysomnography (PSG). Ninety-nine patients (68% male; 56 ± 10 years old) with acute coronary syndrome were included. PSG was performed within 36 h of admission. A specific 18-question questionnaire (CCU questionnaire) was developed and applied after the PSG. Cronbach's alpha test was used to validate the questionnaire. The Spearman test was used to analyze the correlation between the PSG variables and the questionnaire, and the Kruskal-Wallis test was used to compare the PSG variables among patients with good, regular, or poor sleep. The total sleep time was 265 ± 81 min, sleep efficiency 62 ± 18%, REM sleep 10 ± 7%, apnea/hypopnea index 15 ± 23, and the arousal index 24 ± 15. Cronbach's alpha test was 0.69. The CCU questionnaire showed correlation with the sleep efficiency evaluated by PSG (r: 0.52; p < 0.001). Sleep quality was divided into three categories according to the CCU questionnaire: patients with good sleep had a sleep efficiency of 72 ± 9%, better than those with a regular or poor sleep (60 ± 16% and 53 ± 20%, respectively; p < 0.01). The CCU questionnaire is a feasible and reliable tool to evaluate sleep in the CCU, showing correlation with the PSG sleep efficiency. Copyright © 2015 Elsevier B.V. All rights reserved.
    Sleep Medicine 04/2015; DOI:10.1016/j.sleep.2015.03.014
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    ABSTRACT: To investigate the anatomy of the upper airway (UA) of a representative sample of the adult population of São Paulo city, Brazil, and to identify factors associated with the presence of obstructive sleep apnea syndrome (OSAS), as confirmed using full-night polysomnography (PSG). Cross-sectional study. Population-based sample. A 3-stage sampling procedure was used to proportionally recruit adult residents of São Paulo city according to gender, age, and socioeconomic status. A complete evaluation was performed, including a systematic evaluation of the UA prior to conducting PSG. Nine-hundred ninety-three (90.2%) of the participants were seen by an ear, nose, and throat (ENT) specialist. Individuals who were diagnosed with OSAS (32.9%) presented a higher frequency of nasal symptoms and structural abnormalities (both nasal and oropharyngeal) compared with those without OSAS. No anatomical differences were observed in the facial skeleton. An abnormal nasal structure visible via anterior rhinoscopy was the only UA factor predicting OSAS after adjustments for the other common OSAS risk factors (male sex, aging, obesity, and increased neck circumference). This is the first study in which a systematic evaluation of the UA was followed by a sleep study in a population-based sample. In a sample of the general population that had not previously been screened for OSAS, having an abnormal nasal structure was found to be a risk factor for OSAS, in conjunction with other well-established clinical and demographic factors, such as male gender, increased age, increased neck circumference, and body mass index. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.
    Otolaryngology Head and Neck Surgery 03/2015; DOI:10.1177/0194599815577598
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    ABSTRACT: Although the cognitive-enhancing abilities after modafinil have been demonstrated, its effects on memory consolidation remain overlooked. We investigated the effects of repeated modafinil administration on consolidation of a discriminative avoidance task. Mice were trained in the plus-maze discriminative avoidance task. After training, mice received intraperitonial modafinil (doses of 32, 64 or 128 mg/kg). Animals were treated for more 9 consecutive days; 30 min after the last injection, testing was performed. In addition, the effects of 32 mg/kg modafinil on consolidation at different time points were examined. The smaller dose of modafinil (32 mg/kg) impaired memory consolidation, without modifying anxiety or locomotion. Still, modafinil post-training administration at 1 or 2 h impaired memory persistence. Modafinil impaired memory consolidation in a dose- and time-dependent fashion.
    Acta Neuropsychiatrica 03/2015; DOI:10.1017/neu.2015.16
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    ABSTRACT: Rapid maxillary expansion (RME) is a widely used practice in orthodontics. Scientific evidence shows that RME can be helpful in modifying the breathing pattern in mouth-breathing patients. In order to promote the restoration of physiological breathing we have developed a rehabilitation program associated with RME in children. The aim of the study was a literature review and a model of orofacial rehabilitation in children with obstructive sleep apnea undergoing treatment with rapid maxillary expansion. Muscular training (local exercises and general ones) is the key factor of the program. It also includes hygienic and behavior instructions as well as other therapeutic procedures such as rhinosinusal washes, a postural re-education (Alexander technique) and, if necessary, a pharmacological treatment aimed to improve nasal obstruction. The program should be customized for each patient. If RME is supported by an adequate functional rehabilitation, the possibility to change the breathing pattern is considerably amplified. Awareness, motivation and collaboration of the child and their parents, as well as the cooperation among specialists, such as orthodontist, speech therapist, pediatrician and otolaryngologist, are necessary conditions to achieve the goal.
    12/2014; 7(4):225-233. DOI:10.1016/j.slsci.2014.11.002
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    Dataset: SLEEP2387
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    ABSTRACT: Introdução o sucesso da cirurgia faríngea no tratamento da síndrome da apnéia obstrutiva do sono (SAOS) depende da adequada seleção de pacientes. Objetivo propor um novo estadiamento para indicação de cirurgia faríngea na SAOS. Método estudo retrospectivo, onde foram inclusos, 54 pacientes submetidos a amigdalectomia ampliada, divididos em 6 estádios. Estádio I: pacientes com tonsilas palatinas graus 3/4 e índice de Mallampati modificado (IMM) 1/2; Estádio II: tonsilas palatinas 3/4 e IMM 3/4; Estádio III: tonsilas palatinas 1/2 e IMM 1/2; Estádio IV: tonsilas palatinas 1/2 e IMM 3/4; Estádio V: IMC (índice de massa corpórea) ≥ com tonsilas palatinas 3/4 e IMM 1,2,3 ou 4. Estádio VI: IMC ≥ kg/m2 com tonsilas palatinas 1ou2 e IMM 1, 2, 3, ou 4. Resultados as taxas de sucesso cirúrgico foram de 88,9%; 75,0%; 35,7%; 38,5% e 100,0% nos estádios I a V. Conclusão a presença de tonsilas palatinas hipertróficas foi o fator anatômico em comum nos estádios de maior sucesso (I, II e V), independente do IMC. Apesar do IMM classe III e IV diminuir a taxa de sucesso da cirurgia em pacientes com tonsilas hipertróficas (estádio II), a presença de IMM classe I e II não favoreceu o sucesso cirúrgico em pacientes com tonsilas normotróficas (estádio III).
    Brazilian journal of otorhinolaryngology 11/2014; 80(6). DOI:10.1016/j.bjorl.2014.09.003
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    ABSTRACT: The aim of the present study was to characterize the temporal patterns of sleep and wakefulness in a sample of the adult subjects from São Paulo city. All subjects filled the Morningness/Eveningness Questionnaire (MEQ) and wore an actigraph for at least three consecutive days. A total of 359 subjects were considered for the analyses. The mean age was 43±14 years, the mean body mass index was 26.7±5.7 kg/m2, and 60% were female. The mean MEQ score was 58.0±10.7. The sleep pattern evaluated by the actigraphic analyses showed that 92% had a monophasic sleep pattern, 7% biphasic, and 1% polyphasic sleep pattern. Cluster analysis, based on time to sleep onset, sleep efficiency, sleep latency, and total sleep time, was able to identify three different groups denominated: morning type, evening type, and undefined type. Morning type subjects were more frequent, older, and had higher MEQ scores than evening type subjects. Our results showed that the actigraph objectively assessed the sleep-wake cycle and was able to discriminate between morning and evening type individuals. These findings suggest that the actigraph could be a valuable tool for assessing temporal sleep patterns, including the circadian preferences.
    09/2014; 164(3). DOI:10.1016/j.slsci.2014.09.012
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    ABSTRACT: National surveys are relevant for the study of sleep epidemiology since they can provide specific data about sleep in large dimension with important implications for the health system. Thus, the aim of this study was to investigate the prevalence of sleep complaints among the Brazilian population using a randomized cluster sample according to region and socioeconomic class. For this, a 3-stage sampling technique was used to randomly select Brazilian subjects of both genders older than 16 years. A total of 2017 subjects, from 132 different cities, were selected to estimate prevalence in the Brazilian population with a sampling error of ±2%. Questions about sleep complaints were administered face-to-face by Instituto Datafolha interviewers on April 10 and 16, 2012. Data were expanded using a weighted variable. The results showed that 76% of the study population suffers from at least 1 sleep complaint, indicating that approximately 108 million Brazilians may be affected by sleep disorders. On average, each subject had 1.9 sleep problems with the most common complaints being light and insufficient sleep, snoring, moving a lot during sleep, and insomnia, which usually occurred more than 3 times per week. Low income was associated with higher number of sleep complaints only in Northeast and Southeast regions. In conclusion, this study showed a high prevalence of sleep complaints in a sample of the Brazilian population, suggesting that sleep disorders may be markedly frequent in the Brazilian population with a possible correlation with the socioeconomic situation of the interviewed subjects.
    09/2014; 30(3). DOI:10.1016/j.slsci.2014.08.001
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    ABSTRACT: Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart®) system. Results: A total of 767 participants (461 men) with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat) was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001). After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.
    Arquivos Brasileiros de Cardiologia 09/2014; DOI:10.5935/abc.20140142
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    ABSTRACT: Objective: To systematically analyze the studies that have examined the effect of continuous positive airway pressure (CPAP) on blood pressure (BP) in patients with resistant hypertension and obstructive sleep apnea (OSA). Methods: Design - meta-analysis of observational studies and randomized controlled trials (RCTs) indexed in PubMed and Ovid (All Journals@Ovid). participants: individuals with resistant hypertension and OSA; interventions - CPAP treatment. Results: A total of six studies met the inclusion criteria for preintervention to postintervention analyses. The pooled estimates of mean changes after CPAP treatment for the ambulatory (24-h) SBP and DBP from six studies were -7.21 mmHg [95% confidence interval (CI): -9.04 to -5.38; P < 0.001; I-2 58%) and -4.99 mmHg (95% CI: -6.01 to -3.96; P < 0.001; I-2 31%), respectively. The pooled estimate of the ambulatory SBP and DBP from the four RCTs showed a mean net change of -6.74 mmHg [95% CI: -9.98 to -3.49; P < 0.001; I-2 61%] and -5.94 mmHg (95% CI: -9.40 to -2.47; P = 0.001; I-2 76%), respectively, in favor of the CPAP group. Conclusion: The pooled estimate shows a favorable reduction of BP with CPAP treatment in patients with resistant hypertension and OSA. The effects sizes are larger than those previously reported in patients with OSA without resistant hypertension.
    Journal of Hypertension 09/2014; 32(12). DOI:10.1097/HJH.0000000000000372
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    ABSTRACT: Previous studies have suggested that brain-derived neurotrophic factor (BDNF) participates in the homeostatic regulation of sleep. The objective of this study was to investigate the influence of the Val66Met functional polymorphism of the BDNF gene on sleep and sleep EEG parameters in a large population-based sample. In total 337 individuals participating in the São Paulo Epidemiologic Sleep Study were selected for analysis. None of the participants had indications of a sleep disorder, as measured by full-night polysomnography and questionnaire. Spectral analysis of the EEG was carried out in all individuals using fast Fourier transformation of the oscillatory signals for each EEG electrode. Sleep and sleep EEG parameters in individuals with the Val/Val genotype were compared with those in Met carriers (Val/Met and Met/Met genotypes). After correction for multiple comparisons and for potential confounding factors, Met carriers showed decreased spectral power in the alpha band in stage one and decreased theta power in stages two and three of nonrapid-eye-movement sleep, at the central recording electrode. No significant influence on sleep macrostructure was observed among the genotype groups. Thus, the Val66Met polymorphism seems to modulate the electrical activity of the brain, predicting interindividual variation of sleep EEG parameters. Further studies of this and other polymorphic variants in potential candidate genes will help the characterization of the molecular basis of sleep. © 2014 Wiley Periodicals, Inc.
    Journal of Neuroscience Research 08/2014; 92(8). DOI:10.1002/jnr.23380
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    ABSTRACT: Aim: Parkinson's disease (PD) patients frequently present visual hallucinations (VHs) that have been associated with depression, old age, and cognitive impairment. Sleep abnormalities are also related to these factors. The aim of this study is to evaluate risk factors, particularly sleep alterations, associated with VHs in PD. Methods: This is a cross-sectional evaluation of consecutive patients from a Movement Disorder's clinics. Patients were clinically evaluated, and behavioral questionnaires were applied in a face-to-face interview. Results: Among 100 PD patients (67% male, mean age = 65·0 ± 10·4), VHs were present in 28% of cases; individuals with VHs had worse sleep quality (Pittsburgh Sleep Questionnaire Index) and more severe sleep disturbances [Parkinson's Disease Sleep Scale (PDSS)]. Logistic regression analysis showed that vivid dreams and Unified Parkinson's Disease Rating Scale (UPDRS) I scores (i.e., mentation, behavior, and mood symptoms) are independently associated with VHs. Our data show that the presence of vivid dreams is associated with VHs in PD and reaffirm that VHs are linked to cognitive impairment. Conclusions: Investigating vivid dreams may help the identification of VHs in PD. Identifying vivid dreams can be hard considering that patients may fail to report symptoms for the fear of the stigma associated with psychosis and dementia.
    Neurological Research 07/2014; DOI:10.1179/1743132814Y.0000000418
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    ABSTRACT: With increases life expectancy, the incidence of undesirable manifestations of menopause has increased as well. The effects of lost ovarian function include progressive decrease in estradiol secretion, trophic changes in the breast, vasomotor symptoms, anxiety, depression, and sleep disorders. Insomnia, which has physiological consequences and can result in a loss of quality of life, is prevalent in women after menopause. Hormone therapy has been widely used to reduce menopausal symptoms, but its use in recent years has been questioned because of the reported risks of cardiovascular events and increased incidence of tumors. This controversy has generated significant interest in non-hormonal treatments among both physicians and patients. Our previous research has shown a positive effect of massage therapy on menopausal symptoms. We explored the hypothesis that massage therapy would produce beneficial effects in postmenopausal women through inflammatory and immunological changes. Recent results from self-report questionnaires have shown improvements in sleep pattern and quality of life following massage therapy. These findings demonstrate the effectiveness of massage therapy for the treatment of postmenopausal symptoms, particularly insomnia, and indicate that it is a promising line of research.
    06/2014; 27(2). DOI:10.1016/j.slsci.2014.09.005
  • B108. DIAGNOSTIC AND PROGNOSTIC ASSESSMENT OF PULMONARY VASCULAR DISEASE. May 1, 2014, A3863-A3863; 05/2014
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    ABSTRACT: Objective Although many studies have shown the evolution of sleep parameters across the lifespan, not many have included a representative sample of the general population. The objective of this study was to describe age-related changes in sleep structure, sleep respiratory parameters and periodic limb movements of the adult population of São Paulo. Methods We selected a representative sample of the city of São Paulo, Brazil that included both genders and an age range of 20–80 years. Pregnant and lactating women, people with physical or mental impairments that prevent self-care and people who work every night were not included. This sample included 1024 individuals who were submitted to polysomnography and structured interviews. We subdivided our sample into five-year age groups. One-way analysis of variance was used to compare age groups. Pearson product–moment was used to evaluate correlation between age and sleep parameters. Results Total sleep time, sleep efficiency, percentage of rapid eye movement (REM) sleep and slow wave sleep showed a significant age-related decrease (P < 0.05). WASO (night-time spent awake after sleep onset), arousal index, sleep latency, REM sleep latency, and the percentage of stages 1 and 2 showed a significant increase (P < 0.05). Furthermore, apnea–hypopnea index increased and oxygen saturation decreased with age. The reduction in the percentage of REM sleep significantly correlated with age in women, whereas the reduction in the percentage of slow wave sleep correlated with age in men. The periodic limb movement (PLM) index increased with age in men and women. Conclusions Sleep structure and duration underwent significant alterations throughout the aging process in the general population. There was an important correlation between age, sleep respiratory parameters and PLM index. In addition, men and women showed similar trends but with different effect sizes.
    Sleep Medicine 04/2014; DOI:10.1016/j.sleep.2013.11.791
  • Karin Mitiyo Correa, Lia Rita Azeredo Bittencourt, Sergio Tufik, Helena Hachul
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    ABSTRACT: To evaluate the frequency of sleep disorders, such as obstructive sleep apnea, restless leg syndrome and insomnia in overweight/obese postmenopausal women seen in a climacteric sleep disorders clinic. Thirty-four postmenopausal women were selected using the following inclusion criteria: age between 50 and 70 years; at least 12 months of amenorrhea; body mass index (BMI) greater than or equal to 25 kg/m2; and sleep-related complaints with at least one previous polysomnography. Patients provided responses to 6 questionnaires related to sleep characteristics and menopausal symptoms. Weight and height were measured using standardized scales, and abdomen and hip circumferences were also measured. The statistical analyses were performed using the χ2 test for qualitative variables and using Student's t-test for quantitative variables. Patients' characteristics were as follows: mean age of 60.35 years; mean BMI of 31.62; an average of 11.61 postmenopausal years and an average Kupperman Index of 19. A total of 85.2% of the patients had a waist/hip ratio of less than 0.8. The Epworth Scale score was greater than or equal to 9 in 50% of patients; 68% had sleep disturbances according to the Pittsburgh Index, and 68% were classified as high-risk for sleep apnea by the Berlin Questionnaire. On polysomnography, 70.58% of the patients had a sleep efficiency lower than 85%; 79.41% had a sleep latency of less than 30 min; 58.82% had a REM sleep latency of less than 90 min, and 44.11% had mild apnea. When the groups were compared, a linear association was identified between BMI and the AHI average, and a relationship between high BMI and use of drugs for thyroid treatment was found. There was a high prevalence of sleep-disordered breathing, initial insomnia, fragmented sleep, and thyroid disorders in the group with higher BMI.
    Revista brasileira de ginecologia e obstetrićia: revista da Federação Brasileira das Sociedades de Ginecologia e Obstetrícia 02/2014; 36(2):90-6.
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    ABSTRACT: Due to increasing demand for sleep services, there has been growing interest in ambulatory models of care for patients with obstructive sleep apnea (OSA). The implementation of alternative approaches to the current management by full polysomnography (PSG) in the sleep laboratory is necessary for diagnosing this syndrome due to the high cost of full-night PSG. A good alternative option for OSA diagnosis is portable monitoring (PM), which is known for its accuracy, ease of management and lower cost when compared with full PSG. PM has not been well validated for OSA diagnosis in patients with medical comorbidities or in elderly individuals and children. PM may be recommended as an alternative method to PSG for patients with high clinical risk for OSA. In the present review, we describe the use of PM for OSA diagnosis and evaluate the current progress, costs, limitations and applications of these devices in various groups of patients, particularly for patients with comorbid diseases.
    Expert Review of Respiratory Medicine 12/2013; DOI:10.1586/17476348.2014.850421
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    ABSTRACT: Inflammatory markers like tumour necrosis factor-alpha (TNF-α) have been related to erectile dysfunction (ED) and may interact with other cardiovascular risk factors such as obstructive sleep apnoea syndrome (OSAS). The aim of this study was to examine the inflammatory, metabolic and hormonal profile of men with or without ED complaints and/or OSAS recruited through the Epidemiologic Sleep Study (EPISONO). A sample of 363 men completed sexual questionnaires for ED and had physical and blood examinations. OSAS was evaluated by polysomnography and clinical assessment. The blood samples were used for determination of TNF-α, interleukin-6, leptin, cholesterol and fractions, triglycerides, homocysteine, glucose and hormonal levels. After controlling for confounding factors, men with ED complaints presented higher systolic blood pressure and TNF-α, independent of OSAS. Significant interaction between ED and OSAS was only observed for neck circumference, which was higher in ED men with OSAS than men with OSAS without ED and men with ED without OSAS. Binary logistic regression showed that the predictor factors for ED were age >43 years, myocardial infarction events, TNF-α and systolic blood pressure. Finally, a receiver-operating characteristics curve suggested a cut-off point of 9.95 pg/mL for TNF-α with sensitivity of 60% and specificity of 59% in men with ED complaints. Furthermore, there was a significant association between high levels of TNF-α (>9.95 pg/mL) and the presence of ED complaints. The results showed that there was an association between TNF-α levels and ED complaints in men independent of OSAS.
    Andrology 10/2013; DOI:10.1111/j.2047-2927.2013.00136.x

Publication Stats

1k Citations
347.61 Total Impact Points

Institutions

  • 2000–2015
    • Universidade Federal de São Paulo
      • Departamento de Psicobiologia
      San Paulo, São Paulo, Brazil
  • 2010
    • University of São Paulo
      • Hospital das Clínicas (FMUSP)
      Ribeirão Preto, Estado de Sao Paulo, Brazil
  • 2009
    • University of the Witwatersrand
      Johannesburg, Gauteng, South Africa
    • Universidade Metodista de São Paulo
      San Paulo, São Paulo, Brazil
  • 2002
    • University of British Columbia - Vancouver
      • Department of Oral Health Sciences
      Vancouver, British Columbia, Canada