REM sleep obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) can occur in both rapid eye movement (REM) and non-REM sleep or be limited to REM sleep, when the upper airway is most prone to collapse due to REM sleep atonia. Respiratory events are usually longer and more desaturating in REM than in NREM sleep. The prevalence of REM OSA is higher in women than in men and REM OSA usually occurs in the context of mild-moderate OSA based on the apnoea-hypopnoea index calculated for the entire sleep study. Studies have highlighted some detrimental consequences of REM OSA; for example, its frequent association with systemic hypertension and a degree of excessive daytime sleepiness similar to that found in nonsleep-stage-dependent OSA. Moreover, REM OSA could increase cardiometabolic risk. Continuous positive airway pressure (CPAP) treatment aimed at preventing REM OSA should be longer than the 4 h usually considered as good compliance, since REM sleep occurs mostly during the second half of the night. Unfortunately, patients with REM OSA show poor adherence to CPAP. Alternative non-CPAP treatments might be a good choice for REM OSA, but data are lacking. This review summarises the available data on REM OSA and critically examines the weaknesses and strengths of existing literature.

Obstructive sleep apnea and comorbidities: a dangerous liaison.

Obstructive sleep apnea (OSA) is a highly prevalent disease, and is traditionally associated with increased cardiovascular risk. The role of comorbidities in OSA patients has emerged recently, and new conditions significantly associated with OSA are increasingly reported. A high comorbidity burden worsens prognosis, but some data suggest that CPAP might be protective especially in patients with comorbidities. Aim of this narrative review is to provide an update on recent studies, with special attention to cardiovascular and cerebrovascular comorbidities, the metabolic syndrome and type 2 diabetes, asthma, COPD and cancer. Better phenotypic characterization of OSA patients, including comorbidities, will help to provide better individualized care. The unsatisfactory adherence to CPAP in patients without daytime sleepiness should prompt clinicians to examine the overall risk profile of each patient in order to identify subjects at high risk for worse prognosis and provide the optimal treatment not only for OSA, but also for comorbidities.

Sleep Disturbances in COPD are Associated with Heterogeneity of Airway Obstruction.

Individuals with Chronic Obstructive Pulmonary Disease (COPD) experience sleep disturbances due to the impact of respiratory symptoms on sleep quality. We explored whether sleep disturbances in COPD are linked to heterogeneity of airway constriction. The impact of breathing problems on sleep quality was measured in consecutive COPD outpatients with the COPD and Asthma Sleep Impact Scale (CASIS) questionnaire. Impulse oscillometry technique (IOS) was employed to assess heterogeneity of airway constriction. Subjects with a previous or concomitant diagnosis of asthma or obstructive sleep apnea (OSA) were excluded. Fifty COPD subjects (M/F 40/10; age: 71 ± 8 yrs, Body Mass Index (BMI): 26.2 ± 4.7 kg/m2, Forced Expiratory Volume in the first second (FEV1): 65 ± 25% predicted; mean ± SD) were enrolled. The mean CASIS score was 36 ± 3.3, and the R5-R20 value was 0.2 ± 0.15 kPa s L-1. The CASIS score was significantly higher in subjects with increased R5-R20 (>0.07 kPa s L-1) (39 ± 24; p = 0.02) compared to normal R5-R20 (21 ± 17). When subjects were categorized on the basis of lung function in severely versus non severely obstructed (FEV1 ≤ or >50% predicted) or air trappers versus non air trappers (Residual Volume, RV ≥ or <120% predicted) the CASIS score remained unchanged (for FEV1: 37 ± 23 versus 33 ± 25, respectively, p = 0.61; for RV: 30 ± 20 versus 40 ± 23, p = 0.16). Sleep disturbances due to COPD symptoms are associated with heterogeneity of airway constriction, possibly reflecting peripheral airway dysfunction.

Use of autobilevel ventilation in patients with obstructive sleep apnea: An observational study.

Continuous positive airway pressure (CPAP) is the first-choice treatment for obstructive sleep-disordered breathing. Automatic bilevel ventilation can be used to treat obstructive sleep-disordered breathing when CPAP is ineffective, but clinical experience is still limited. To assess the outcome of titration with CPAP and automatic bilevel ventilation, the charts of 356 outpatients (obstructive sleep apnea, n = 242; chronic obstructive pulmonary disease + obstructive sleep apnea overlap, n = 80; obesity hypoventilation syndrome [OHS], n = 34; 103 females) treated for obstructive sleep-disordered breathing from January 2014 to April 2017 were reviewed. Positive airway pressure titration was considered successful in the case of sleep-disordered breathing resolution (apnea-hypopnea index <10/hr) with cumulative time at SaO2  < 90% (CT90%) <10% and/or improved daytime arterial blood gases at the end of titration. CPAP was effective in 268 patients (75.0%). CPAP treatment failure (n = 88) occurred in 13.6% of obstructive sleep apnea, 32.5% of overlap, and 85.3% of OHS patients. Compared with successful CPAP cases, patients undergoing the automatic bilevel ventilation trial showed higher body mass index (39.3 ± 10.5 kg/m2 versus 34.8 ± 6.9 kg/m2 , p < 0.0001), worse mean nocturnal SaO2 (89.2 ± 4.0% versus 91.3 ± 4.0%, p < 0.003) and CT90% (40.6 ± 28.6% versus 24.0 ± 23.3%), but similar age (62.8 ± 11.9 years versus 60.5 ± 12.0 years, p = 0.11), apnea-hypopnea index (39.4 ± 23.2/hr versus 41.0 ± 21.2/hr, p = 0.55) and oxygen desaturation index (37.8 ± 23.5/hr versus 39.2 ± 21.1/hr, p = 0.61) at diagnosis. Automatic bilevel ventilation was successful in 79.5% of CPAP treatment failures (n = 70). Automatic bilevel ventilation failure was independently associated with baseline body mass index >40 kg/m2 (odds ratio 6.16, confidence interval 1.50-25.17, p = 0.011) and CT90% >42% (odds ratio 5.87, confidence interval 1.39-24.83, p = 0.016). During follow-up, automatic bilevel ventilation treatment failed in seven patients (10%), and compliance was similar in CPAP (4.5 ± 2.2 hr) and automatic bilevel ventilation (5.2 ± 2.3 hr, p = 0.09) groups. Automatic bilevel ventilation was useful to treat sleep-disordered breathing, but failed in patients with severe OHS.

Endurance training: is it bad for you?

EDUCATIONAL AIMS: To illustrate the characteristics of endurance exercise training and its positive effects on health.To provide an overview on the effects of endurance training on airway cells and bronchial reactivity.To summarise the current knowledge on respiratory health problems in elite athletes. Endurance exercise training exerts many positive effects on health, including improved metabol-ism, reduction of cardiovascular risk, and reduced all-cause and cardiovascular mortality. Intense endurance exercise causes mild epithelial injury and inflammation in the airways, but does not appear to exert detrimental effects on respiratory health or bronchial reactivity in recreational/non-elite athletes. Conversely, elite athletes of both summer and winter sports show increased susceptibility to development of asthma, possibly related to environmental exposures to allergens or poor conditioning of inspired air, so that a distinct phenotype of "sports asthma" has been proposed to characterise such athletes, who more often practise aquatic and winter sports. Overall, endurance training is good for health but may become deleterious when performed at high intensity or volume.