Endocrine disorders in obstructive sleep apnoea syndrome: A bidirectional relationship.

Obstructive sleep apnoea (OSA) is a common disorder characterized by recurrent episodes of apnoea or hypopnea due to total or partial pharyngeal collapse and temporary upper airway obstruction during sleep. The prevalence of OSA is increasing and currently affects about 30% of men and 13% of women in Europe. Intermittent hypoxia, oxidative stress, systemic inflammation, and sleep fragmentation resulting from OSA can provoke subsequent cardiometabolic disorders. The relationships between endocrine disorders and OSA are complex and bidirectional. Indeed, several endocrine disorders are risk factors for OSA. Compared with the general population, the prevalence of OSA is increased in patients with obesity, hypothyroidism, acromegaly, Cushing syndrome, and type 1 and 2 diabetes. In some cases, treatment of the underlying endocrine disorder can improve, and occasionally cure, OSA. On the other hand, OSA can also induce endocrine disorders, particularly glucose metabolism abnormalities. Whether continuous positive airway pressure (CPAP) treatment for OSA can improve these endocrine disturbances remains unclear due to the presence of several confounding factors. In this review, we discuss the current state-of-the-art based on the review of the current medical literature for key articles focusing on the bidirectional relationship between endocrine disorders and OSA and the effects of treatment. Screening of OSA in endocrine patients is also discussed, as it remains a subject of debate.

Obstructive sleep apnea is not associated with diabetic retinopathy in diabetes: a prospective case-control study.

PURPOSE: Diabetic retinopathy (DR) is the most common ocular complication of type 2 diabetes mellitus (T2D) and is associated with diabetes duration, glycemic control, and hypertension (HTN). Obstructive sleep apnea (OSA) is frequent in T2D and is associated with poor glycemic control. However, it is unclear if there is an association between OSA and DR. This study aimed to assess whether or not the presence of OSA in patients with T2D was associated with DR. METHODS: In this prospective case-control study, consecutive patients with DM attending the ophthalmology clinics were recruited to include patients with DR (cases) and without DR (controls). OSA was diagnosed by attended polysomnography (PSG). Blood pressure and a fasting morning blood sample, including glycosylated hemoglobin (HbA1c), were recorded. Patients were matched for age, body mass index (BMI), gender, and T2D duration. RESULTS: Thirty diabetic patients with DR were matched with 30 controls. In all patients, the prevalence of moderate-to-severe OSA was 57%. In the logistic regression analysis, DR was associated with increased HbA1c (OR 2.63, 95% CI 1.35-5.16, p = 0.004) but not with any PSG parameter. In the DR group, PSG parameters were not associated with the severity of ocular disease (non-proliferative, proliferative, presence/absence of macular edema). The proliferative aspect of DR was correlated with age (p = 0.017). DR occurred more frequently in uncontrolled diabetes compared to well-controlled diabetes (80% vs 38%, p = 0.029). CONCLUSIONS: In patients with T2D, the presence of DR is not associated with OSA, but with poorly controlled T2D.

Tailored individual Yoga practice improves sleep quality, fatigue, anxiety, and depression in chronic insomnia disorder.

BACKGROUND: Chronic insomnia disorder (CI) is a prevalent sleep disorder that can lead to disturbed daytime functioning and is closely associated with anxiety and depression. First-choice treatment is cognitive behavioral therapy (CBT-I). Other mind-body interventions, such as Tai-chi and Yoga, have demonstrated subjective improvements in sleep quality. The purpose of this study was to assess the efficacy of Yoga for improvement of subjective and objective sleep quality as well as measures of anxiety, depression, sleepiness, and fatigue in patients with CI. METHODS: Adults with CI were prospectively included in this single group pre-post study. Baseline assessments included home polysomnography (PSG), 7-day actigraphy, and questionnaires (Pittsburgh Sleep Quality Index questionnaire (PSQI), Hospital Anxiety Depression scale (HADS), Epworth Sleepiness Scale (ESS), Pichot fatigue scale (PS)). Patients practiced Viniyoga, an individualised Yoga practice with daily self-administered exercises, for 14 weeks. Assessments were repeated at the end of Yoga practice. RESULTS: Twenty-one patients completed the study. Objective sleep measurements revealed no change in PSG parameters after Yoga practice, but a decrease in arousals on actigraphy (p < 0.001). Subjective symptoms improved for all questionnaires (PSQI, p < 0.001; HAD-A, p = 0.020, HAD-D, p = 0.001, ESS, p = 0.041, PS, p = 0.010). In univariate correlations, decrease in PSQI was associated with increase in sleep stage N3 (p < 0.001) on PSG. CONCLUSIONS: We have demonstrated a positive impact of individualized Yoga practice on subjective parameters related to sleep and daytime symptoms in CI, resulting in fewer arousals on actigraphy. Yoga could be proposed as a potentially useful alternative to CBT-I in CI, as it is easy to practice autonomously over the long-term. However, given the design of the present study, future prospective controlled studies should first confirm our results. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03314441 , date of registration: 19/10/2017.

Pressure adjustment is the most useful intervention for improving compliance in telemonitored patients treated with CPAP in the first 6 months of treatment.

PURPOSE: Telemonitoring (TMg) for patients treated with continuous positive airway pressure (CPAP) is now routine care in some sleep labs. The purpose of the present study was to identify technical interventions associated with improved CPAP compliance in a real-life cohort of newly telemonitored patients with obstructive sleep apnea (OSA) during the first 6 months of treatment. METHODS: All patients with moderate-to-severe OSA (apnea-hypopnea index (AHI) ≥ 15/h) who were newly treated with CPAP were included in the study and telemonitored. A group educational session was scheduled after 1 month. Technical interventions were performed at the patient's request and during scheduled visits and the impact of each intervention on CPAP therapy compliance was collected. RESULTS: Between May 2018 and Dec 2019, 349 patients newly diagnosed with OSA were hospitalized in the sleep lab for CPAP titration and 212 patients were included (mean age 54.6 ± 13.1 years, mean BMI 31.7 ± 5.8 kg/m2, mean AHI 42.8 ± 22.0). TMg acceptance rate was 87%. Mean 6-month compliance was 275 ± 154 min, 13% stopped CPAP, and 17% were non-compliant. Correlations were observed between BMI (r = 0.15, p = 0.029), median and 95th percentile leaks (r = -0.23 and -0.18, p = 0.016 and 0.002), and CPAP compliance. During follow-up, 92 interventions were required, mainly for mask change (n = 80). Pressure modification (n = 16) was the only intervention that increased CPAP use > 30 min/night, p = 0.021. CONCLUSION: Pressure modification was the only adaptation that significantly increased CPAP compliance during the first 6 months. Remote TMg allows providing daily, accurate, and immediate feedback that could help clinicians to confirm that the CPAP treatment is effective.

Telemonitoring for the Follow-Up of Obstructive Sleep Apnea Patients Treated with CPAP: Accuracy and Impact on Therapy.

Continuous positive airway pressure (CPAP) telemonitoring (TMg) has become widely implemented in routine clinical care. Objective measures of CPAP compliance, residual respiratory events, and leaks can be easily monitored, but limitations exist. This review aims to assess the role of TMg in CPAP-treated obstructive sleep apnea (OSA) patients. We report recent data related to the accuracy of parameters measured by CPAP and try to determine the role of TMg in CPAP treatment follow-up, from the perspective of both healthcare professionals and patients. Measurement and accuracy of CPAP-recorded data, clinical management of these data, and impacts of TMg on therapy are reviewed in light of the current literature. Moreover, the crucial questions of who and how to monitor are discussed. TMg is a useful tool to support, fine-tune, adapt, and control both CPAP efficacy and compliance in newly-diagnosed OSA patients. However, clinicians should be aware of the limits of the accuracy of CPAP devices to measure residual respiratory events and leaks and issues such as privacy and cost-effectiveness are still a matter of concern. The best methods to focus our efforts on the patients who need TMg support should be properly defined in future long-term studies.

Post-discharge critical COVID-19 lung function related to severity of radiologic lung involvement at admission.

Lung function impairment persists in 55% of critical COVID-19 patients three months after ICU discharge. Patient lung function, exercise capacity, radiologic, and quality of life data suggest impairment is related to radiologic lung involvement at admission.

Photoplethysmography in Normal and Pathological Sleep.

This article presents an overview of the advancements that have been made in the use of photoplethysmography (PPG) for unobtrusive sleep studies. PPG is included in the quickly evolving and very popular landscape of wearables but has specific interesting properties, particularly the ability to capture the modulation of the autonomic nervous system during sleep. Recent advances have been made in PPG signal acquisition and processing, including coupling it with accelerometry in order to construct hypnograms in normal and pathologic sleep and also to detect sleep-disordered breathing (SDB). The limitations of PPG (e.g., oxymetry signal failure, motion artefacts, signal processing) are reviewed as well as technical solutions to overcome these issues. The potential medical applications of PPG are numerous, including home-based detection of SDB (for triage purposes), and long-term monitoring of insomnia, circadian rhythm sleep disorders (to assess treatment effects), and treated SDB (to ensure disease control). New contact sensor combinations to improve future wearables seem promising, particularly tools that allow for the assessment of brain activity. In this way, in-ear EEG combined with PPG and actigraphy could be an interesting focus for future research.

Cardiometabolic comorbidities in obstructive sleep apnea patients are related to disease severity, nocturnal hypoxemia, and decreased sleep quality.

BACKGROUND: Obstructive sleep apnea syndrome (OSA) is currently recognized as an independent risk factor for hypertension, arrhythmia, coronary heart disease, stroke, and metabolic disorders (e.g. diabetes, dyslipidemia). In clinical practice, apnea-hypopnea index (AHI) is the marker used to classify disease severity and guide treatment. However, AHI alone does not sufficiently identify OSA patients at risk for cardiometabolic comorbidities. With this in mind, the aim of this retrospective study was to determine whether some polysomnographic parameters (e.g. apnea-hypopnea duration, sleep structure, nocturnal hypoxemia) are specifically associated with cardiometabolic comorbidities in OSA. METHODS: In this retrospective study, 1717 patients suffering from moderate/severe OSA were included between 2013 and 2017. Data on demographics, comorbidities, and polysomnographic characteristics were collected and analyzed to identify factors associated with cardiometabolic complications. RESULTS: The medical files of 1717 patients (68% male) were reviewed. The mean AHI was 43.1 +/- 27.7 with 57.3% of patients suffering from severe OSA, and 52% from at least one cardiovascular comorbidity (CVCo). Diabetes affected 22% of the patients and 27% exhibited dyslipidemia. Patients affected by CVCos were older, and more often women and non-smokers. These patients also had worse sleep quality, and a more marked intermittent/global nocturnal hypoxemia. With regard to diabetes, diabetics were older, more often non-smoker, non-drinker women, and were more obese. These patients also exhibited more severe OSA, especially in non-REM (NREM) sleep, worse sleep quality, and a more marked intermittent/global nocturnal hypoxemia. Dyslipidemia was more frequent in the absence of alcohol consumption, and was associated with OSA severity, decreased sleep quality, and longer AH in REM sleep. CONCLUSIONS: This study identifies demographic and polysomnographic factors associated with cardiometabolic comorbidities. Patients (especially women) suffering from more severe OSA, longer sleep apneas and hypopneas, worse sleep quality, and marked intermittent/global nocturnal hypoxemia are more likely to develop cardiometabolic comorbidities. This should stimulate clinicians to obtain adequate treatment in this population.

Prevalence of undiagnosed glucose intolerance and type 2 diabetes in patients with moderate-to-severe obstructive sleep apnea syndrome.

PURPOSE: Overweight and obesity are major causal factors for obstructive sleep apnea syndrome (OSAS), providing insight into why one third of patients with OSAS suffer from diabetes mellitus and another third from glucose intolerance. However, a significant proportion of the general population remains undiagnosed for glucose metabolism disorders. The primary aim of this study was to establish the prevalence of known and newly diagnosed glucose metabolism disorders in patients with moderate and severe OSAS referred to the sleep lab for continuous positive airway pressure (CPAP) therapy. METHODS: We prospectively included consecutive patients with moderate or severe OSAS referred for CPAP therapy. A fasting blood sample was collected to determine glycosylated hemoglobin (HbA1c), glucose, and homeostatic model assessment (HOMA) index. Baseline demographic data and medication intake were recorded. RESULTS: Of 280 consecutive patients (70% men, mean ± SD body mass index 33 ± 7 kg/m2, apnea-hypopnea index 49 ± 25), 22% exhibited diabetes and 44% glucose intolerance. Undiagnosed diabetes and glucose intolerance was found in 79 of 280 patients (28%). Insulin resistance was associated with OSAS severity in multivariate linear regression analysis (regression coefficient 2.40 [95% CI 0.07-4.72]; p = 0.04). CONCLUSION: In this population of overweight and obese patients with moderate and severe OSAS, 66% of patients had diabetes or glucose intolerance and 28% were newly diagnosed. Diabetes and glucose intolerance were not related to OSAS severity, contrary to insulin resistance. These data suggest that there is value in systematic screening for glucose metabolism disorders in all patients with moderate and severe OSAS.

African ethnicity is associated with a higher prevalence of diabetes in obstructive sleep apnea patients: results of a retrospective analysis.

PURPOSE: Obstructive sleep apnea (OSA) syndrome is a well-recognized independent risk factor for cardiovascular disease and its prevalence is increasing. OSA symptomology, polysomnographic features, and comorbidities are heterogeneous among patients. Ethnicity is thought to influence OSA phenotypes, but extensive knowledge of OSA ethnic patterns is lacking. The primary aim of the present study was to compare comorbidities in Caucasian and African OSA. Secondary aims were to observe OSA symptomatology, polysomnographic characteristics, and CPAP adherence in these two ethnic groups. METHODS: In this retrospective study, 1717 patients suffering from moderate/severe OSA were included between 2013 and 2017. Data on demographics, symptomatology, comorbidities, polysomnographic characteristics, and CPAP adherence were collected. Data were analyzed to identify potential differences between Caucasians and Africans. RESULTS: Despite healthier lifestyles and lower BMI, a higher prevalence of diabetes but less cardiac comorbidities and dyslipidemia was observed in the African population. Younger African patients (< 56 years) suffered more from cognitive impairment than Caucasians and both younger and older Africans complained more of nighttime choking than Caucasians. In analysis of polysomnographic data, Africans had higher apnea-hypopnea index (AHI) in REM sleep, lower supine AHI, lower desaturation time, and lower periodic leg movements index. CONCLUSIONS: Compared with Caucasians, African OSA showed a particular comorbidity profile. There are younger patients who exhibit more diabetes but less cardiac comorbidities than the Caucasians. African diabetics should be more promptly referred for OSA testing. Moreover, as they suffer more often from choking and cognitive impairment, OSA treatment could positively impact their quality of life.

Prevalence of newly established thyroid disorders in patients with moderate-to-severe obstructive sleep apnea syndrome.

BACKGROUND: Hypothyroidism can directly cause obstructive sleep apnea (OSA) but may also contribute to it through its impact on the metabolic syndrome. The purpose of this study was to establish the prevalence of known and newly diagnosed overt and subclinical hypothyroidism (SCH) among patients with OSA. METHODS: We prospectively included all consecutive moderate or severe OSA patients referred for CPAP therapy. A fasting blood sample was collected to determine thyroid-stimulating hormone (TSH) and free T4 (FT4) levels. RESULTS: A total of 280 patients were included (70% male). Mean ± SD body mass index (BMI) and apnea-hypopnea index (AHI) were 33 ± 7 kg/m2 and 49 ± 25, respectively. Median (range) serum TSH levels and mean ± SD FT4 levels were comparable between severe and moderate OSA (1.7 (1.3-2.6) vs 2.1 (1.2-2.8); p = 0.378 and 15.3 ± 2.3 vs 15.3 ± 2.3; p = 0.981). TSH and FT4 levels were not correlated with AHI (p = 0.297 and p = 0.370, respectively), but TSH was correlated with BMI (p = 0.049).Of all patients, 8.9% had increased serum TSH levels (severe and moderate OSA patients had similar levels (p = 0.711)) and 8.2% were newly diagnosed patients (no differences were observed between severe and moderate OSA (p = 0.450)). A total of 16.4% of patients had some type of thyroid disorder. Thyroid function parameters were associated with BMI but not with the severity of OSA. CONCLUSION: In our population of moderate or severe OSA, 16% of patients had a thyroid problem and 8% of these were newly diagnosed with SCH.

Relationship between the sensation of activity limitation and the results of functional assessment in asthma patients.

OBJECTIVE: In asthma patients, the assessment of activity limitation is based on questions evaluating how limited the patient feels in their activities. However, the lack of functional data complicates the interpretation of the answers. We aimed to evaluate the intensity of relationships between the patient's perception of activity limitation and the results of several functional tests. METHODS: Twenty patients complaining of asthma exacerbation were invited to complete three scores (Chronic Respiratory Disease questionnaire, Asthma Control Questionnaire, Hospital Anxiety and Depression scale). They also underwent lung function measurements, a 6-minute walk test and a cardio-pulmonary exercise test. In addition, physical activity was studied by actigraphy. Spearman's rank correlation coefficients between the patient's perception of activity limitation and each of the other parameters were analysed. RESULTS: Five parameters were significantly correlated with the perception of activity limitation: ACQ question 4, related to dyspnea (rs 0.74, p < 0.001); Emotion domain of the Chronic Respiratory Disease questionnaire (rs -0.57, p = 0.02); HAD anxiety (rs 0.48, p = 0.032); HAD depression (rs 0.46, p = 0.041); ACQ question 6, related to reliever use (rs 0.46, p = 0.046). No parameters from the lung function test, 6MWT, CPET or actigraphy, were significantly correlated with the perception of activity limitation. CONCLUSIONS: In response to questions about limitation of activity, patients do not specifically answer mentioning physical limitation but rather the psychological burden associated with this constraint.

The Feasibility of Tracheal Oxygen Supplementation during Flexible Bronchoscopy.

BACKGROUND: Hypoxemia is a frequent adverse event occurring during flexible bronchoscopy and is usually prevented by close monitoring and, if needed, oxygen supplementation by nasal cannula. OBJECTIVE: We aim to demonstrate that tracheal oxygen supplementation during flexible bronchoscopy is a feasible, safe and effective method to restore oxygen saturation levels after oxygen desaturation. METHODS: In a first phase, we compare oxygen supplementation by the tracheal or nasal route in a single blinded cross-over design in healthy volunteers. In a second phase, we study patients referred for diagnostic flexible bronchoscopy, who desaturate despite oxygen supplementation by nasal cannula, in order to assess the ability to correct hypoxemia through tracheal oxygen supplementation. RESULTS: In the first phase, the mean capillary partial pressure of oxygen was 181 mm Hg when oxygen at a flow rate of 4 liters/min was administered by the tracheal route, compared to 125 mm Hg by the nasal route (p < 0.001). The capillary partial pressure of carbon dioxide was not significantly different. During 950 bronchoscopic procedures in the second phase of the trial, 30 patients desaturated below 90% despite oxygen supplementation by nasal cannula. In 22 out of these 30 patients, switching to the tracheal route resulted in a correction of the saturation within 120 s. In the remaining 8 patients, saturation levels were corrected after increasing the oxygen flow rate to 4 liters/min. After restoring saturation levels, the bronchoscopy could be completed in 25 of 30 patients. CONCLUSIONS: Tracheal oxygen supplementation is safe, feasible and an effective way to restore oxygen saturation levels during flexible bronchoscopy.

Chronic Obstructive Pulmonary Disease: CT Quantification of Airway Dimensions, Numbers of Airways to Measure, and Effect of Bronchodilation.

PURPOSE: To determine the effect of bronchodilation on airway indexes reflecting airway disease in patients with chronic obstructive pulmonary disease (COPD) and to determine the minimum number of segmental and subsegmental airways required. MATERIALS AND METHODS: This study was approved by the local ethical committee, and written informed consent was obtained from all subjects. Twenty patients with COPD who had undergone pre- and postbronchodilator pulmonary function tests and computed tomographic (CT) examinations were prospectively included. Eight healthy volunteers underwent two CT examinations. Luminal area and wall thickness (WT) of third- and fourth-generation airways were measured twice by three readers. The percentage of total airway area occupied by the wall and the square root of wall area at an internal perimeter of 10 mm (√WAPi10) were calculated. The effects of pathologic status, session, reader, bronchodilation, and CT examination were assessed by using mixed linear model analyses. The number of airways to measure for a definite percentage error of √WAPi10 was computed by using a bootstrap method. RESULTS: There were no significant session, reader, or bronchodilation effects on WT in third-generation airways and √WAPi10 in patients with COPD (P values ranging from .187 to >.999). WT in third-generation airways and √WAPi10 were significantly different in patients with COPD and control subjects (P = .018 and <.001, respectively). Measuring 12 third- or fourth-generation airways ensured a maximal 10% error of √WAPi10. CONCLUSION: WT in third-generation airways and √WAPi10 are not significantly different before and after bronchodilation and are different in patients with COPD and control subjects. Twelve is the minimum number of third- or fourth-generation airways required to ensure a maximal 10% error of √WAPi10. (©) RSNA, 2015 Clinical trial registration no. NCT01142531 Online supplemental material is available for this article.

Factors Associated with Persistent Obstructive Sleep Apnea After Bariatric Surgery: A Narrative Review.

The prevalence of obstructive sleep apnea (OSA) among the bariatric surgery population is estimated to be 45-70%. However, weight loss obtained by bariatric surgery is not always associated with full remission of OSA, suggesting that other confounding factors are present. This article aims to review the current literature, focusing on factors that could predict the persistence of OSA after bariatric surgery. For this purpose, relevant studies of more than 50 patients that assessed pre- and post-operative presence and severity of OSA detected by poly(somno)graphy (PG/PSG) in bariatric populations were collected. Six retrospective and prospective studies were evaluated that included 1302 OSA patients, with a BMI range of 42.6 to 56 kg/m2, age range of 44.8 to 50.7 years, and percentage of women ranging from 45% to 91%. The studies were very heterogeneous regarding type of bariatric surgery, diagnostic criteria for OSA and OSA remission, and delay of OSA reassessment. OSA remission was observed in 26% to 76% of patients at 11-12 months post-surgery. Loss to follow-up was high in all studies, leading to a potential underestimation of OSA remission. Based on this limited sample of bariatric patients, age, pre-operative OSA severity, proportion of weight loss, and type 2 diabetes (T2D) were identified as factors associated with OSA persistence but the results were inconsistent between studies regarding the impact of age and the magnitude of weight loss. Several other factors may potentially lead to OSA persistence in the bariatric surgery population, such as fat distribution, ethnicity, anatomical predisposition, pathophysiological traits, supine position, and REM-predominant hypopnea and apnea. Further well-conducted multicentric prospective studies are needed to document the importance of these factors to achieve a better understanding of OSA persistence after bariatric surgery in obese patients.

An Unusual Cause of Increasing Excessive Daytime Sleepiness in a CPAP-treated Obstructive Sleep Apnea Patient.

The onset of narcolepsy type 1 (NT1) occurs after 50 years of age in less than 2% of the cases. In older adults, the diagnosis is often delayed due to the presence of neurological degenerative and inflammatory comorbidities and overlapping sleep disorders. We report the case of a 63-year-old man with a 5-year history of excessive daytime sleepiness (EDS) and a 2-year diagnosis of obstructive sleep apnea syndrome (OSAS), which. OSAS was confirmed by respiratory polygraphy that showed an apnea-hypopnea index (AHI) of 71 events/hour of sleep associated with significant nocturnal hypoxemia (lowest oxygen saturation: 53%), which lead to the initiation of continuous positive airway pressure (CPAP) treatment. Cognitive complaints, unexplained spells of dizziness, and lack of improvement in EDS with CPAP led to further diagnostic investigation of infectious, inflammatory, and neurodegenerative disorders. Low hypocretin levels in the cerebrospinal fluid (CSF) confirmed the diagnosis of NT1, and the patient's symptoms improved with the treatment with pitolisant. Though exceptional in older adults, NT1 should be suspected in the presence of atypical EDS with neurological complaints, unexplained dizzy spells, or OSAS that resists the CPAP treatment. Low levels of hypocretin in the CSF are highly specific and rule out other neurological and sleep disorders.

Correlation between sleep parameters, physical activity and quality of life in somnolent moderate to severe obstructive sleep apnea adult patients.

PURPOSE: Several symptoms are described in obstructive sleep apnea (OSA), including excessive daytime sleepiness, depressive mood and neurocognitive dysfunction. However, few studies examined the relationship between objective physical activity, quality of life and sleep parameters. The purpose of this study was to determine sleep parameters (evaluated by actigraphy and polysomnography) implied in the occurrence of impaired physical activity and reduced quality of life in somnolent moderate to severe OSA patients. METHODS: We reviewed retrospectively data of 75 somnolent moderate to severe (Apnea-Hypopnea Index > 20) OSA patients. Data of 5-days actigraphy and polysomnography were analysed. They all completed the Nottingham Health Profile questionnaire (NHP). Sleep parameters associated with physical activity and quality of life were assessed. RESULTS: Patients were mainly obese (mean BMI 36) and males (53 %). Controlling for age and BMI, physical activity, expressed as number of steps walked/day, is associated with OSA severity in REM sleep (p = 0.05). Subjective somnolence was not associated with reduced physical activity. Regarding quality of life, "sleep", "energy" and "emotional reactions" scored highest; and patients evaluated correctly their activity impairment through the "mobility" item of NHP questionnaire. CONCLUSIONS: Low level of physical activity is associated with increasing OSA severity in somnolent moderate to severe OSA patients but is not linked to subjective somnolence. These patients describe concomitantly a severely impaired quality of life in several domains, and the negative perception in the "mobility" domain is effectively related to an objective low level of physical activity.