Objective: To study the effects that gender and obesity have on excessive daytime sleepiness (EDS) in individuals with obstructive sleep apnea-hypopnea syndrome (OSAHS), as well as to identify factors associated with EDS in such individuals. Methods: A total of 300 consecutive patients who completed the clinical evaluation satisfactorily and whose polysomnography showed an apnea-hypopnea index (AHI) > 10 events/hour of sleep were selected from a sleep clinic population for inclusion in the study. Results: Mean age was 47 ± 11 years, and mean AHI was 52.1 ± 29.2 events/hour of sleep. Females presented higher mean age, lower EDS scores and less time in apnea . Mean EDS score was 14.7 ± 7.2. The EDS score correlated best with body movements (r = 0.43; p < 0.01), respiratory events during sleep (r = 0.40; p < 0.01), duration of apnea (r = 0.40; p < 0.01), peripheral oxygen saturation (SpO2; r = -0.38; p < 0.01) and AHI (r = 0.37; p < 0.01). Mean body mass index (BMI) was 30.2 ± 5.3 kg/m2. Overweight, obesity and morbid obesity were observed in 41, 44 and 5.3% of cases, respectively. Disease severity correlated most strongly with BMI (r = 0.51; p < 0.01). Conclusions: Higher mean age, lower EDS scores and less time spent in sleep apnea time in apnea were associated with being female. Fragmented sleep, number/duration of respiratory events during sleep, SpO2 levels and obesity were associated with sleepiness. The BMI had a significant effect on OSAHS severity.

Keywords: Sleep apnea, obstructive; Sleep apnea syndromes; Polysomnography; Sleep stages; Obesity.

Objective: To determine the prevalence of obstructive sleep apnea syndrome (OSAS), as well as to identify factors associated with a greater risk of developing OSAS, among truck drivers. Methods: The study population comprised 209 truck drivers (mean age, 38.8 years; 98.5% males) at two branches of a transportation company. The mean body mass index was 26.5 ± 4.4 kg/m2. The participants completed questionnaires regarding sociodemographic data, physical activity and OSAS. The prevalence of OSAS was estimated using the Berlin Questionnaire, associations between OSAS and the factors studied being assessed through univariate and multivariate regression analysis. Results: The prevalence of OSAS in the population was 11.5%. Of the 209 truck drivers, 72 (34.5%) reported having fallen asleep while driving and 81 (38.7%) reported snoring. The following variables were found to present statistically significant associations with OSAS: informal employment (OR = 0.27; p = 0.01); body mass index ≥ 25 kg/m2 (OR = 13.64; p = 0.01); and poor sleep quality (OR = 3.00; p = 0.02). Conclusions: The prevalence of OSAS in this study was lower than that reported in other studies of truck drivers and yet higher that that observed for the general population. In addition, our results suggest that work characteristics, such as employment status, are associated with OSAS. These data show the relevance of considering work activity in studies of factors associated with OSAS.

Keywords: Sleep apnea, obstructive; Sleep disorders; Questionnaires.

Objective: To investigate whether the presence of obstructive sleep apnea syndrome (OSAS) alters the perception of respiratory symptoms and quality of life in COPD patients, by using specific questionnaires, as well as to determine whether scales for assessing daytime sleepiness and for screening for OSAS can be used in the triad of OSAS, COPD, and obesity. Methods: We included 66 patients diagnosed with mild-to-moderate or severe COPD and presenting with a body mass index > 27 kg/m2. After polysomnography, patients completed the Epworth sleepiness scale (ESS), the Berlin questionnaire (BQ), the modified Medical Research Council (mMRC) scale, the Baseline Dyspnea Index (BDI), and the Saint George's Respiratory Questionnaire (SGRQ). Results: Patients were first divided into two groups: COPD + OSAS (n = 46); and COPD-only (n = 20). The COPD + OSAS group was subdivided into a COPD + mild-to-moderate OSAS group (n = 32) and a COPD + severe OSAS group (n = 14), all of which were compared with the COPD-only group. There was a significant difference in mean FEV1 (L) between the COPD + OSAS groups and the COPD-only group (p = 0.073). The presence of the triad did not lead to significantly higher ESS scores, and scores > 10 had a specificity of 0.58. The BQ did not identify high risk for OSAS in the presence of the triad (specificity of 0.31). There were no significant differences in domain or total scores of the SGRQ between the COPD + OSAS groups and the COPD-only group. Conclusions: The confounding factors present in the triad of OSAS, COPD, and obesity prevented the perception of increased daytime sleepiness and high risk for OSAS. We observed no worsening of dyspnea perception or quality of life.

Keywords: Sleep apnea, obstructive; Pulmonary disease, chronic obstructive; Obesity; Surveys and questionnaires.

Objective: Obstructive sleep apnea syndrome (OSAS) has a high prevalence and carries significant cardiovascular risks. It is important to study new therapeutic approaches to this disease. Positional therapy might be beneficial in reducing the apnea-hypopnea index (AHI). Imaging methods have been employed in order to facilitate the evaluation of the airways of OSAS patients and can be used in order to determine the effectiveness of certain treatments. This study was aimed at determining the influence that upper airway volume, as measured by cervical CT, has in patients diagnosed with OSAS. Methods: This was a quantitative, observational, cross-sectional study. We evaluated 10 patients who had been diagnosed with OSAS by polysomnography and on the basis of the clinical evaluation. All of the patients underwent conventional cervical CT in the supine position. Scans were obtained with the head of the patient in two positions (neutral and at a 44° upward inclination), and the upper airway volume was compared between the two. Results: The mean age, BMI, and neck circumference were 48.9 ± 14.4 years, 30.5 ± 3.5 kg/m2, and 40.3 ± 3.4 cm, respectively. The mean AHI was 13.7 ± 10.6 events/h (range, 6.0-41.6 events/h). The OSAS was classified as mild, moderate, and severe in 70%, 20%, and 10% of the patients, respectively. The mean upper airway volume was 7.9 cm3 greater when the head was at a 44° upward inclination than when it was in the neutral position, and that difference (17.5 ± 11.0%) was statistically significant (p = 0.002). Conclusions: Elevating the head appears to result in a significant increase in the caliber of the upper airways in OSAS patients.

Keywords: Sleep apnea, obstructive/prevention and control; Sleep apnea, obstructive/therapy; Tomography.

Madelung's disease, or multiple symmetric lipomatosis, is a rare disease, characterized by accumulation of unencapsulated fat, generally located symmetrically around the neck and shoulders. Here, we present the case of a patient with diffuse lipomatosis accompanied by obstructive sleep apnea due to cervical involvement and facial deformity, which made it necessary to use nasal pillows for ventilation. The patient was hospitalized with a diagnosis of pneumonia and required noninvasive ventilation due to severe hypercapnia. A brief review of the literature was made, and we describe and discuss the investigation of this rare clinical case.

Keywords: Lipomatosis, multiple symmetrical; Sleep apnea, obstructive; Continuous positive airway pressure; Masks.

Objective: To determine the prevalence of risk factors for obstructive sleep apnea syndrome in interstate bus drivers. Methods: This study involved 262 professional interstate bus drivers employed by a Brazilian company headquartered in the Federal District. The drivers were evaluated using a questionnaire designed to assess respiratory sleep disorders, the Epworth Sleepiness Scale, test of sustained attention, test of divided attention and anthropometric measurements. Results: Body weight was found to be above the ideal in 68% of the drivers evaluated, 34% of which had a neck circumference = 42 cm. During the study period, the drivers reported using tobacco (27%), cola-based soft drinks (55%), alcohol (65%) and coffee (88%). The Epworth Sleepiness Scale score was = 10 points in 28%. Snoring was reported by 36%, sleep apnea by 5%, a sensation of suffocation during sleep by 12%, restless sleep by 29% and drowsiness while driving by 48%. There were 42% who had been involved in transit accidents, 7.6% of which were attributed to hypersomnolence. Those scoring higher than 10 of the Epworth Sleepiness Scale presented lower levels of sustained attention. In addition, a reduction in divided attention was found to correlate with greater daytime sleepiness and larger neck circumference. Conclusion: The rate of stimulant use found in the group of drivers evaluated is alarming. The high prevalence of daytime sleepiness indicates that attentiveness is reduced in this population.

Keywords: Automobile driving; Sleep apnea, obstructive; Work schedule tolerance; Psychometrics; Risk factors; Attention; Questionnaires

Objective: To evaluate lung function and inspiratory muscle strength, correlating them with exercise tolerance, in obese individuals with obstructive sleep apnea syndrome (OSAS). Methods: The sample comprised 31 adult subjects with moderate-to-severe OSAS diagnosed by polysomnography. We used spirometry to measure FVC, FEV1, and FVC/FEV1 ratio, using pressure manometry to measure MIP and MEP. The incremental shuttle walk test (ISWT) and the six-minute walk test (6MWT) were used in order to determine functional exercise capacity. Results: In this sample, the mean values for FVC (% of predicted), FEV1 (% of predicted): MIP, and MEP were 76.4 ± 12.3%, 80.1 ± 6.3%, 60.0 ± 21.9 cmH2O, and 81.3 ± 22.2 cmH2O, respectively. The mean distances covered on the ISWT and 6MWT were 221 ± 97 m and 480.8 ± 67.3 m, respectively. The ISWT distance showed moderate positive correlations with FVC (r = 0.658; p = 0.001) and FEV1 (r = 0.522; p = 0.003). Conclusions: In this sample of obese subjects with untreated OSAS, lung function, inspiratory muscle strength, and exercise tolerance were all below normal. In addition, we found that a decline in lung function, but not in respiratory muscle strength, was associated with exercise tolerance in these patients.

Keywords: Sleep apnea syndromes; Exercise tolerance; Respiratory function tests; Respiratory muscles.

The physiopathology of obstructive sleep apnea syndrome is multifactorial. Gender and obesity status, as well as genetic, anatomic, and hormonal factors, together with ventilatory drive, interact in a diverse manner in the physiopathology and clinical expression of the disease. Obesity is the main risk factor, since increases in body mass index, visceral fat, and neck circumference are strong predictors of the disease. Progesterone increases the activity of the upper airway dilator muscles and therefore plays a protective role in premenopausal women. This explains the fact that the prevalence of the disease is higher in postmenopausal patients, in patients with polycystic ovary syndrome, as well as in males. Evidence supports the fact that, as individuals grow older, there is a decrease in muscle tonus, with a consequent reduction in the dimensions of the upper airway lumen. Craniofacial anomalies, such as in retrognathia or micrognathia, are accompanied by posterior positioning of the tongue and can result in narrowing of the upper airway lumen. Finally, decreased ventilatory drive has been detected in patients with obstructive sleep apnea syndrome and hypercapnia.

Keywords: Sleep apnea obstructive/physiopathology; Body mass index; Obesity

Objective: To identify risk factors for respiratory complications after adenotonsillectomy in children ≤ 12 years of age with obstructive sleep apnea who were referred to the pediatric ICU (PICU). Methods: A cross-sectional historical cohort study analyzing 53 children after adenotonsillectomy who met predetermined criteria for PICU referral in a tertiary level teaching hospital. The Student's t-test, Mann-Whitney test, and chi-square test were used to identify risk factors. Results: Of the 805 children undergoing adenotonsillectomy between January of 2006 and December of 2012 in the teaching hospital, 53 were referred to the PICU. Twenty-one children (2.6% of all those undergoing adenotonsillectomy and 39.6% of those who were referred to the PICU) had respiratory complications. Of those 21, 12 were male. The mean age was 5.3  2.6 years. A high apnea-hypopnea index (AHI; p = 0.0269), a high oxygen desaturation index (ODI; p = 0.0082), a low SpO2 nadir (p = 0.0055), prolonged orotracheal intubation (p = 0.0011), and rhinitis (p = 0.0426) were found to be independent predictors of respiratory complications. Some of the complications observed were minor (SpO2 90-80%), whereas others were major (SpO2 ≤ 80%, laryngospasm, bronchospasm, acute pulmonary edema, pneumonia, and apnea). Conclusions: Among children up to 12 years of age with OSA, those who have a high AHI, a high ODI, a low SpO2 nadir, or rhinitis are more likely to develop respiratory complications after adenotonsillectomy than are those without such characteristics.

Keywords: Postoperative complications; Tonsillectomy; Sleep apnea, obstructive.

Objective: To study the effects of nocturnal hypoxemia in patients with chronic obstructive pulmonary disease without obstructive sleep apnea syndrome. Methods: We studied 21 patients-10 desaturators and 11 nondesaturators-submitted to arterial blood gas analysis, polysomnography, spirometry, cardiopulmonary exercise testing (cycle ergometer), and hand-grip dynamometry, as well as measurements of maximal inspiratory pressure, maximal expiratory pressure, and C-reactive protein (CRP) levels. Patients with arterial oxygen tension > 60 mmHg were included; those with an apnea-hypopnea index > 5 events/hour of sleep were excluded. Maximal oxygen uptake, maximal power, systolic blood pressure, diastolic blood pressure (DBP), and maximal heart rate were measured during exercise in order to detect hemodynamic alterations. Patients presenting CRP levels above 3 mg/L were considered CRP-positive. Results: Minimal peripheral oxygen saturation during sleep was significantly higher among nondesaturators (p = 0.03). More desaturators presented CRP > 3 mg/L (p < 0.05). No differences were observed in terms of any variables, However, mean peripheral oxygen saturation during sleep correlated with DBP and maximal inspiratory pressure (p < 0.001 and p = 0.001, respectively). Conclusions: Although nocturnal hypoxemia does not reduce exercise capacity or hand-grip strength in patients with mild/moderate COPD, its effect on maximal exercise DBP seems to depend on the degree of hypoxemia. In addition, there is a positive relationship between maximal inspiratory pressure and mean peripheral oxygen saturation during sleep, as well as evidence of pronounced inflammatory activation in patients with nocturnal hypoxemia.

Keywords: Pulmonary disease, chronic obstructive; Exercise test; Anoxia; Respiratory function tests.

Symptoms of sleep-disordered breathing, especially obstructive sleep apnea syndrome (OSAS), are common in asthma patients and have been associated with asthma severity. It is known that asthma symptoms tend to be more severe at night and that asthma-related deaths are most likely to occur during the night or early morning. Nocturnal symptoms occur in 60-74% of asthma patients and are markers of inadequate control of the disease. Various pathophysiological mechanisms are related to the worsening of asthma symptoms, OSAS being one of the most important factors. In patients with asthma, OSAS should be investigated whenever there is inadequate control of symptoms of nocturnal asthma despite the treatment recommended by guidelines having been administered. There is evidence in the literature that the use of continuous positive airway pressure contributes to asthma control in asthma patients with obstructive sleep apnea and uncontrolled asthma.

A case of obstructive sleep apnea syndrome (OSAS) with narcoleptic features is described; polysomnographic studies were carried out and revealed a severe nocturnal respiratory impairment due to apneic episodes. A multiple sleep latency test (MSLT) showed early REM sleep onset in two out of five series. Nasal CPAP utilization improved the quality of nocturnal sleep and reverted all narcoleptic features in the next day's MSLT.

Keywords: Obstructive sleep apnea syndrome (OSAS). Narcolepsy. Sleep deprivation. CPAP.

Objective: To investigate the symptoms most frequently found in children with a polysomnographic diagnosis of obstructive sleep apneahypopnea syndrome (OSAHS). Methods: We evaluated 38 children consecutively referred to the sleep laboratory with suspicion of OSAHS between June of 2003 and December of 2004. The patients were submitted to a pre-sleep questionnaire and to polysomnography. Results: The mean age was 7.8 ± 4 years (range, 2-15 years), and 50% of the children were male. Children without apnea accounted for 7.9% of the sample. The obstructive sleep apnea observed in the remainder was mild in 42.1%, moderate in 28.9% and severe in 22.1%. Severe cases of apnea were most common among children under the age of six (pre-school age). In children with OSAHS, the most common symptoms were snoring and nasal obstruction, which were observed in 74.3 and 72.7% of the children, respectively. Excessive sleepiness and bruxism were seen in 29.4 and 34.3%, respectively, and reflux disease was seen in only 3.1%. Restless legs and difficulty in falling asleep were identified in 65 and 33%, respectively. All of the children diagnosed with severe OSAHS also presented snoring and bruxism. Conclusions: Snoring and nasal obstruction were the most common symptoms found in our sample of children and adolescents with OSAHS. In addition, OSAHS severity was associated with being in the lower age bracket.

Keywords: Obstructive sleep apnea; Polysomnography; Pediatrics; Snoring.

Objective: To identify the main predictive factors for obtaining a diagnosis of obstructive sleep apnea (OSA) in patients awaiting bariatric surgery. Methods: Retrospective study of consecutive patients undergoing pre-operative evaluation for bariatric surgery and referred for in-laboratory polysomnography. Eight variables were evaluated: sex, age, neck circumference (NC), BMI, Epworth Sleepiness Scale (ESS) score, snoring, observed apnea, and hypertension. We employed ROC curve analysis to determine the best cut-off value for each variable and multiple linear regression to identify independent predictors of OSA severity. Results: We evaluated 1,089 patients, of whom 781 (71.7%) were female. The overall prevalence of OSA-defined as an apnea/hypopnea index (AHI) ≥ 5.0 events/h-was 74.8%. The best cut-off values for NC, BMI, age, and ESS score were 42 cm, 42 kg/m2, 37 years, and 10 points, respectively. All eight variables were found to be independent predictors of a diagnosis of OSA in general, and all but one were found to be independent predictors of a diagnosis of moderate/severe OSA (AHI ≥ 15.0 events/h), the exception being hypertension. We devised a 6-item model, designated the NO-OSAS model (NC, Obesity, Observed apnea, Snoring, Age, and Sex), with a cut-off value of ≥ 3 for identifying high-risk patients. For a diagnosis of moderate/severe OSA, the model showed 70.8% accuracy, 82.8% sensitivity, and 57.9% specificity. Conclusions: In our sample of patients awaiting bariatric surgery, there was a high prevalence of OSA. At a cut-off value of ≥ 3, the proposed 6-item model showed good accuracy for a diagnosis of moderate/severe OSA.

Keywords: Polysomnography; Sleep apnea, obstructive; Bariatric surgery.

Objective: To identify fibromyalgia syndrome in patients with sleep disordered breathing. Method: We studied 50 patients seeking treatment at a sleep disorder clinic for snoring, apnea and excessive daytime sleepiness. Sleep disordered breathing was diagnosed through the use of polysomnography. To diagnose fibromyalgia syndrome, patients were evaluated in accordance with the criteria established by the American College of Rheumatology. Results: Of the 50 patients, 32 were male. The mean (± standard deviation) age of the group was 50 ± 12 years. The mean body mass index was 29.7 ± 5.6 kg/m2. The mean apnea-hypopnea index was 36 ± 29 attacks of apnea or hypopnea per hour of sleep. Of the 18 women and 32 men evaluated, 9 and 2, respectively, met the American College of Rheumatology criteria for fibromyalgia syndrome. Conclusion: Considering the fact that the prevalence of fibromyalgia syndrome in the general population is 0.5% for men and 3.4% for women, the more than ten-fold higher proportion of fibromyalgia cases seen in this sample supports the hypothesis that there is an association between sleep disordered breathing and fibromyalgia syndrome.

Keywords: Respiration disorders/complications; Fibromyalgia/complications; Sleep apnea, obstructive; Polysomnography

Objective: To evaluate the performance of the No-Apnea score, a simplified screening instrument for obstructive sleep apnea (OSA), by gender. Methods: This was a cross-sectional study including adults undergoing full polysomnography. The No-Apnea model comprises two items (neck circumference and age) with a total score of 0 to 9. The severity of OSA was categorized, on the basis of the apnea-hypopnea index, as any (≥ 5 events/h), moderate-to-severe (≥ 15 events/h), or severe (≥ 30 events/h). The performance of the No-Apnea instrument was assessed by determining the area under the (ROC) curve (AUC) and by constructing contingency tables. Results: We evaluated a total of 6,606 adults (53.8% men). For categorizing the level of OSA severity, the No-Apnea score had a sensitivity of 83.9-93.0% and a specificity of 57.3-35.2%. At all OSA severity levels, the No-Apnea score exhibited higher sensitivity and lower specificity in men than in women. The No-Apnea score proved to be an appropriate screening model for patients in general or when separated by gender or severity of OSA (AUC > 0.7 for all). The discriminatory power of the No-Apnea score to predict any, moderate-to-severe, and severe OSA was similar between genders (p = 0.109, p = 0.698, and p = 0.094, respectively). Conclusions: In a sample of adults referred to the sleep laboratory, there was no significant difference between men and women in terms of the discriminatory power of the No-Apnea instrument in for screening for OSA severity.

Keywords: Sleep apnea, obstructive/diagnosis; Polysomnography; Sex; Surveys and questionnaires.