Distance follow-up by a remote medical care centre improves adherence to CPAP in patients with obstructive sleep apnoea over the short and long term.

BACKGROUND: Adherence to continuous positive air pressure (CPAP) in patients with obstructive sleep apnoea (OSA) has remained invariably low over the last decades. Remote monitoring of the nocturnal CPAP treatment, within telemedicine (TM)-based follow-up programs, in these patients has been suggested as a potential tool to improve adherence and release the workload of sleep units. The aim of this study was therefore to assess whether a follow-up program carried out by a Remote Medical Care Centre (RMCC), outside the sleep unit, improves adherence to CPAP in the short and long term in patients with OSA. METHODS: In this pilot protocol, we enrolled 37 patients starting CPAP in our Sleep Centre (SC). After three months of standard care in our SC, patients initiated a six-month remote follow-up carried out by the RMCC, functioning as an intermediary between patients and SC. Monthly reports and indication for face-to-face visits were sent to the SC for six months. After this period patients returned to usual care for one year. Results were compared with those obtained in 38 patients (controls) followed with usual care over the same time range. RESULTS: Mean nightly use of CPAP increased from 3.2 ± 2.4 h pre-RMCC to 5.2 ± 1.9 h post-RMCC (p < 0.0001). Nights/month of CPAP use improved from 19.8 ± 9.2 to 25.2 ± 2.5 (p < 0.05) and nights/month with CPAP use >4 h from 12.5 ± 10 to 21.03 ± 8.9 (p < 0.05). This improvement remained stable after 12 months from the return of patients to usual care. No significant changes in CPAP use were observed in controls over the time. CONCLUSION: A six-month follow-up through a remote facility can significantly improve adherence to CPAP in the short and long term. This pilot study provides a solid base for the design of multicentre randomized trials focusing on new models which are able to increase the long-term efficacy of TM programs.

Beat-to-beat cardiac repolarization lability increases during hypoxemia and arousals in obstructive sleep apnea patients.

Obstructive sleep apnea (OSA) is associated with the progression of cardiovascular diseases, arrhythmias, and sudden cardiac death (SCD). However, the acute impacts of OSA and its consequences on heart function are not yet fully elucidated. We hypothesized that desaturation events acutely destabilize ventricular repolarization, and the presence of accompanying arousals magnifies this destabilization. Ventricular repolarization lability measures, comprising heart rate corrected QT (QTc), short-time-variability of QT (STVQT), and QT variability index (QTVI), were calculated before, during, and after 20,955 desaturations from lead II electrocardiography signals of 492 patients with suspected OSA (52% men). Variations in repolarization parameters were assessed during and after desaturations, both with and without accompanying arousals, and groupwise comparisons were performed based on desaturation duration and depth. Regression analyses were used to investigate the influence of confounding factors, comorbidities, and medications. The standard deviation (SD) of QT, mean QTc, SDQTc, and STVQT increased significantly (P < 0.01), whereas QTVI decreased (P < 0.01) during and after desaturations. The changes in SDQT, mean QTc, SDQTc, and QTVI were significantly amplified (P < 0.01) in the presence of accompanying arousals. Desaturation depth was an independent predictor of increased SDQTc (ß = 0.405, P < 0.01), STVQT (ß = 0.151, P < 0.01), and QTVI (ß = 0.009, P < 0.01) during desaturation. Desaturations cause acute changes in ventricular repolarization, with deeper desaturations and accompanying arousals independently contributing to increased ventricular repolarization lability. This may partially explain the increased risk of arrhythmias and SCD in patients with OSA, especially when the OSA phenotype includes high hypoxic load and fragmented sleep.NEW & NOTEWORTHY Nocturnal desaturations are associated with increased ventricular repolarization lability. Deeper desaturations with accompanying arousals increase the magnitude of alterations, independent of confounding factors, comorbidities, and medications. Changes associated with desaturations can partially explain the increased risk of arrhythmias and sudden cardiac death in patients with OSA, especially in patients with high hypoxic load and fragmented sleep. This highlights the importance of detailed electrocardiogram analytics for patients with OSA.

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.

Sleep and cardiometabolic comorbidities in the obstructive sleep apnoea-COPD overlap syndrome: data from the European Sleep Apnoea Database.

Aim: The impact of obstructive sleep apnoea (OSA)-COPD overlap syndrome (OVS) on sleep quality and cardiovascular outcomes has not been fully explored. We aimed to compare clinical and polysomnographic characteristics of patients with OVS versus patients with OSA, and to explore pathophysiological links between OVS and comorbidities. Study design and methods: This cross-sectional analysis initially included data from 5600 patients with OSA and lung function in the European Sleep Apnoea Database. Two subgroups of patients with OSA (n=1018) or OVS (n=509) were matched (2:1) based on sex, age, body mass index and apnoea-hypopnea index at baseline. Results: After matching, patients with OVS had more severe hypoxia, lower sleep efficiency and presented with higher prevalences of arterial hypertension, ischaemic heart disease and heart failure compared with patients with OSA. OVS was associated with a significant decrease in sleep efficiency (mean difference (ß) -3.0%, 95% CI -4.7 to -1.3) and in nocturnal mean peripheral oxyhaemoglobin saturation (SpO2) (ß -1.1%, 95% CI -1.5 to -0.7). Further analysis revealed that a decrease in forced expiratory volume in 1 s and arterial oxygen tension was related to a decrease in sleep efficiency and in mean nocturnal SpO2. A COPD diagnosis increased the odds of having heart failure by 1.75 (95% CI 1.15-2.67) and systemic hypertension by 1.36 (95% CI 1.07-1.73). Nocturnal hypoxia was strongly associated with comorbidities; the mean nocturnal SpO2 and T90 (increase in time below SpO2 of 90%) were associated with increased odds of systemic hypertension, diabetes and heart failure but the oxygen desaturation index was only related to hypertension and diabetes. Conclusion: Patients with OVS presented with more sleep-related hypoxia, a reduced sleep quality and a higher risk for heart failure and hypertension.

What to expect from the ERS International Congress 2023.

This article provides an overview of the reasons to attend the 2023 ERS Congress, including a summary of the ECM session and the NEXT programme. https://bit.ly/46ghP4g.

Clinical characteristics and positive airway pressure adherence among elderly European sleep apnoea patients from the ESADA cohort.

Background: The prevalence of obstructive sleep apnoea (OSA) is growing as the population is ageing. However, data on the clinical characteristics of elderly patients with OSA and their adherence to positive airway pressure (PAP) treatment are scarce. Methods: Data from 23 418 30-79-year-old OSA patients prospectively collected into the ESADA database during 2007-2019 were analysed. Information on PAP use (h·day-1) in association with a first follow-up visit was available for 6547 patients. The data was analysed according to 10-year age groups. Results: The oldest age group was less obese, less sleepy and had a lower apnoea-hypopnoea index (AHI) compared with middle-aged patients. The insomnia phenotype of OSA was more prevalent in the oldest age group than in the middle-aged group (36%, 95% CI 34-38 versus 26%, 95% CI 24-27, p<0.001). The 70-79-year-old group adhered to PAP therapy equally well as the younger age groups with a mean PAP use of 5.59 h·day-1 (95% CI 5.44-5.75). PAP adherence did not differ between clinical phenotypes based on subjective daytime sleepiness and sleep complaints suggestive of insomnia in the oldest age group. A higher score on the Clinical Global Impression Severity (CGI-S) scale predicted poorer PAP adherence. Conclusion: The elderly patient group was less obese, less sleepy, had more insomnia symptoms and less severe OSA, but were rated to be more ill compared with the middle-aged patients. Elderly patients with OSA adhered to PAP therapy equally well as middle-aged patients. Low global functioning (measured by CGI-S) in the elderly patient predicted poorer PAP adherence.

Adaptive responses to chronic intermittent hypoxia: contributions from the European Sleep Apnoea Database (ESADA) Cohort.

Obstructive sleep apnoea (OSA) is a common disease in the general population, and is associated with increased cardiovascular risk and several comorbidities. Obesity favours upper airway collapsibility, but other pathophysiological traits have been identified, i.e. upper airway muscle activity, modulation of the respiratory drive, and the arousal threshold. OSA causes chronic intermittent hypoxia, inflammatory activation and autonomic imbalance with diurnal and nocturnal sympathetic hyperactivity. Disentangling so many components to investigate the pathogenesis of OSA's consequences is very hard clinically. However, albeit imperfect, clinical medicine constitutes a major source of inspiration for basic research, and a mutual exchange of information is essential between clinicians and physiologists to improve our understanding of disease states. OSA is no exception, and this narrative review will summarize the results of clinical studies performed over the years by the European Sleep Apnoea Database (ESADA) Study Group, to explore the variables linked to markers of intermittent hypoxia as opposed to the traditional assessment of OSA severity based on the frequency of respiratory events during sleep (the Apnoea Hypopnoea Index). The results of the clinical studies indicate that intermittent hypoxia variables are associated with several comorbidities, although evidence of a cause-effect relationship is still missing in many cases. It is also possible that adaptive rather than maladaptive responses could be evoked by intermittent hypoxia. The intensity, duration and frequency of intermittent hypoxia episodes causing adaptive rather than maladaptive responses, and their clinical implications, deserve further investigation.

Co-existence of OSA and respiratory diseases and the influence of gender.

INTRODUCTION: Sleep-disordered breathing (SDB), especially obstructive sleep apnea (OSA), is commonly associated with respiratory diseases, such as COPD, asthma and interstitial lung disease. AREAS COVERED: This narrative review aims to comprehensively synthesize the existing information on SDB in respiratory diseases, investigate the role of gender in this association, and highlight the importance of OSA management in improving sleep, quality of life, and disease prognosis in these specific patient populations. EXPERT OPINION: Research indicates a synergistic link between OSA and chronic respiratory diseases, which leads to greater morbidity and mortality compared to each disorder alone. Given the lack of an optimal OSA screening tool for these patients, a comprehensive patient approach and overnight diagnostic sleep study are imperative. Despite the limited evidence available, it seems that gender has an impact on the prevalence, severity, and susceptibility of this coexistence. Recognizing the role of gender in the coexistence of OSA and other respiratory diseases can enhance everyday medical practice and enable clinicians to adopt a more personalized approach toward optimal screening and diagnosis of these patients.

Epidemiology, Physiology and Clinical Approach to Sleepiness at the Wheel in OSA Patients: A Narrative Review.

Sleepiness at the wheel (SW) is recognized as an important factor contributing to road traffic accidents, since up to 30 percent of fatal accidents have been attributed to SW. Sleepiness-related motor vehicle accidents may occur both from falling asleep while driving and from behavior impairment attributable to sleepiness. SW can be caused by various sleep disorders but also by behavioral factors such as sleep deprivation, shift work and non-restorative sleep, as well as chronic disease or the treatment with drugs that negatively affect the level of vigilance. An association between obstructive sleep apnea (OSA) and motor vehicle accidents has been found, with an increasing risk in OSA patients up to sevenfold in comparison to the general population. Regular treatment with continuous positive airway pressure (CPAP) relieves excessive daytime sleepiness and reduces the crash risk. Open questions still remain about the physiological and clinical determinants of SW in OSA patients: the severity of OSA in terms of the frequency of respiratory events (apnea hypopnea index, AHI) or hypoxic load, the severity of daytime sleepiness, concomitant chronic sleep deprivation, comorbidities, the presence of depressive symptoms or chronic fatigue. Herein, we provide a review addressing the epidemiological, physiological and clinical aspects of SW, with a particular focus on the methods to recognize those patients at risk of SW.

Investigation and management of residual sleepiness in CPAP-treated patients with obstructive sleep apnoea: the European view.

Excessive daytime sleepiness (EDS) is a major symptom of obstructive sleep apnoea (OSA), defined as the inability to stay awake during the day. Its clinical descriptors remain elusive, and the pathogenesis is complex, with disorders such as insufficient sleep and depression commonly associated. Subjective EDS can be evaluated using the Epworth Sleepiness Scale, in which the patient reports the probability of dozing in certain situations; however, its reliability has been challenged. Objective tests such as the multiple sleep latency test or the maintenance of wakefulness test are not commonly used in patients with OSA, since they require nocturnal polysomnography, daytime testing and are expensive. Drugs for EDS are available in the United States but were discontinued in Europe some time ago. For European respiratory physicians, treatment of EDS with medication is new and they may lack experience in pharmacological treatment of EDS, while novel wake-promoting drugs have been recently developed and approved for clinical use in OSA patients in the USA and Europe. This review will discuss 1) the potential prognostic significance of EDS in OSA patients at diagnosis, 2) the prevalence and predictors of residual EDS in treated OSA patients, and 3) the evolution of therapy for EDS specifically for Europe.

Application of Inverse-Probability-of-Treatment Weighting to Estimate the Effect of Daytime Sleepiness in Patients with Obstructive Sleep Apnea.

Rationale: Continuous positive airway pressure (CPAP), the first line therapy for obstructive sleep apnea (OSA), is considered effective in reducing daytime sleepiness. Its efficacy relies on adequate adherence, often defined as >4 hours per night. However, this binary threshold may limit our understanding of the causal effect of CPAP adherence and daytime sleepiness, and a multilevel approach for CPAP adherence can be more appropriate. Objectives: In this study, we show how two causal inference methods can be applied on observational data for the estimation of the effect of different ranges of CPAP adherence on daytime sleepiness as measured by the Epworth Sleepiness Scale (ESS). Methods: Data were collected from a large prospective observational French cohort for patients with OSA. Four groups of CPAP adherence were considered (0-4, 4-6, 6-7, and 7-10 h per night). Multivariable regression, inverse-probability-of-treatment weighting (IPTW), and inverse propensity weighting with regression adjustment (IPW-RA) were used to assess the impact of CPAP adherence level on daytime sleepiness. Results: In this study, 9,244 patients with OSA treated by CPAP were included. The mean initial ESS score was 11 (±5.2), with a mean reduction of 4 points (±5.1). Overall, there was evidence of the causal effect of CPAP adherence on daytime sleepiness which was mainly observed between the lower CPAP adherence group (0-4 h) compared with the higher CPAP adherence group (7-10 h). There are no differences by considering higher level of CPAP adherence (>4 h). Conclusions: We showed that IPTW and IPW-RA can be easily implemented to answer questions regarding causal effects using observational data when randomized trials cannot be conducted. Both methods give a direct causal interpretation at the population level and allow the assessment of the appropriate consideration of measured confounders.

Obesity and Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) is characterized by upper airway collapse during sleep. Chronic intermittent hypoxia, sleep fragmentation, and inflammatory activation are the main pathophysiological mechanisms of OSA. OSA is highly prevalent in obese patients and may contribute to cardiometabolic risk by exerting detrimental effects on adipose tissue metabolism and potentiating the adipose tissue dysfunction typically found in obesity. This chapter will provide an update on: (a) the epidemiological studies linking obesity and OSA; (b) the studies exploring the effects of intermittent hypoxia and sleep fragmentation on the adipose tissue; (c) the effects of OSA treatment with continuous positive airway pressure (CPAP) on metabolic derangements; and (d) current research on new anti-diabetic drugs that could be useful in the treatment of obese OSA patients.

Pre-sleep arousal and sleep quality during the COVID-19 lockdown in Italy.

OBJECTIVE: The COVID-19 pandemic has strongly affected daily habits and psychological wellbeing, and many studies point to large modifications in several sleep and sleep-related domains. Nevertheless, pre-sleep arousal during the pandemic has been substantially overlooked. Since hyperarousal represents one of the main factors for the development and the perpetuation of chronic insomnia disorder, the assessment of variables associated with high levels of pre-sleep arousal during the pandemic is clinically relevant. The study aimed to assess the prevalence and predictors of perceived sleep quality and pre-sleep arousal in an Italian sample during the COVID-19 lockdown. METHODS: We used an online survey to collect self-reported sociodemographic, environmental, clinical, sleep, and sleep-related data. Our final sample included 761 participants. RESULTS: Beyond a high frequency of poor sleep quality, depressive and stress symptoms, our results show that almost half of the sample suffered from clinically relevant levels of at least one component (ie, cognitive, somatic) of pre-sleep arousal. Subjects with greater pre-sleep arousal exhibited poorer sleep quality. Also, sleep quality was strongly associated with somatic and cognitive pre-sleep arousal. Regarding the predictors of sleep and sleep-related measures, depressive and event-related stress symptoms were the main factors associated with both poor sleep quality and pre-sleep arousal components. Moreover, specific sociodemographic and environmental variables were uniquely related to sleep quality, cognitive or somatic pre-sleep arousal. CONCLUSIONS: These findings suggest that the assessment of specific sleep-related factors (ie, pre-sleep arousal), together with more global measures of sleep quality, may be crucial to depict the complex impact of the pandemic on sleep, and to help prevent and counteract the spread of insomnia symptoms.

Persistence of the Effects of the COVID-19 Lockdown on Sleep: A Longitudinal Study.

The effects of the COVID-19 pandemic on sleep have been widely documented, but longitudinal evaluations during different phases of the "COVID-19 era" are needed to disentangle the specific consequences of the r145estrictive measures on sleep variables. The aim of this study was to assess the immediate effect of the lockdown's end on sleep and sleep-related dimensions in an Italian sample, also considering the stress and depressive symptoms. We used an online survey to longitudinally collect data on sociodemographic, environmental, clinical, sleep, and sleep-related variables in two time points: during and immediately after the lockdown. The final sample included 102 participants. The large prevalence of poor sleep quality, clinically relevant pre-sleep arousal, and depressive symptoms, as well as poor sleep quality and pre-sleep arousal score observed during the lockdown, remained stable after its end. On the other hand, the prevalence of moderate-to-severe event-related stress and intrusive symptom scores exhibited a drastic reduction after the end of home confinement. Both bedtime and rise time were anticipated after the lockdown, while sleep quality exhibited only a trend of post-lockdown sleep disturbance reduction. Our findings point to a reduced stress level (specific for the intrusive symptomatology) after the end of the lockdown and persistence of sleep problems, suggesting two non-mutually exclusive hypotheses: (a) the strict restrictive measures are not the main cause of sleep problems during the pandemic and (b) home confinement induces long-lasting effects on sleep observable after its end, and a longer period of time might be needed to observe an improvement.

Burden of Comorbidities in Patients with OSAS and COPD-OSAS Overlap Syndrome.

Background and Objectives: Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are usually associated with multi-morbidity. The aim of this study was to retrospectively investigate the prevalence of comorbidities in a cohort of patients with OSAS and COPD-OSAS overlap syndrome (OS) patients and to explore differences between these two groups. Materials and Methods: Included were consecutive OS patients and OSAS patients who had been referred to our sleep laboratory, and were matched in terms of sex, age, BMI, and smoking history. Presence of comorbidities was recorded based on their medical history and after clinical and laboratory examination. Results: The two groups, OS patients (n = 163, AHI > 5/h and FEV1/FVC < 0.7) and OSAS patients (n = 163, AHI > 5/h, and FEV1/FVC > 0.7), did not differ in terms of apnea hypopnea index (p = 0.346), and oxygen desaturation index (p = 0.668). Compared to OSAS patients, OS patients had lower average SpO2 (p = 0.008) and higher sleep time with oxygen saturation <90% (p = 0.002) during sleep, and lower PaO2 (p < 0.001) and higher PaCO2 (p = 0.04) in wakefulness. Arterial hypertension was the most prevalent comorbidity for both OS and OSAS, followed by dyslipidemia, cardiovascular disease (CVD) and diabetes. OS was characterized by a higher prevalence of total comorbidities (median (IQR):2 (1-3) vs. 2 (1-2), p = 0.033), which was due to the higher prevalence of CVD (p = 0.016) than OSAS. No differences were observed in other comorbidities. Conclusions: In OS patients, nocturnal hypoxia and impaired gas exchange in wakefulness are more overt, while a higher burden of CVD is observed among them in comparison to sex-, age- and BMI-matched OSAS patients.

Is kidney a new organ target in patients with obstructive sleep apnea? Research priorities in a rapidly evolving field.

The bidirectional relationship between sleep disordered breathing and chronic kidney disease (CKD) has recently gained a lot of interest. Several lines of evidence suggest the high prevalence of coexistent obstructive sleep apnea (OSA) in patients with CKD and end-stage renal disease (ESRD). In addition, OSA seems to result in loss of kidney function in some patients, especially in those with cardio-metabolic comorbidities. Treatment of CKD/ESRD and OSA can alter the natural history of each other; still better phenotyping with selection of appropriate treatment approaches is urgently needed. The aim of this narrative review is to provide an update of recent studies on epidemiological associations, pathophysiological interactions, and management of patients with OSA and CKD or ESRD.

Excessive Daytime Sleepiness in Obstructive Sleep Apnea Patients Treated With Continuous Positive Airway Pressure: Data From the European Sleep Apnea Database.

Excessive daytime sleepiness (EDS) is a symptom of obstructive sleep apnea (OSA) that resolves under treatment with continuous positive airway pressure (CPAP). In some patients, sleepiness persists despite CPAP treatment. We retrospectively analyzed data on subjective residual EDS, assessed as an Epworth Sleepiness Scale score (ESS) >10, in patients from the European Sleep Apnea Database (n = 4,853, mean age ± SD 54.8 ± 11.8 years, 26.1% females), at baseline and at the first visit (median follow-up: 5 months, interquartile range 3-13). An ESS > 10 occurred in 56% of patients at baseline and in 28.2% of patients at follow-up. Residual EDS was analyzed in 2,190 patients (age: 55.1 ± 12.0 years, 26.1% females) with sleep monitoring data (median follow-up: 3 months, interquartile range 1-15). Sleep studies during CPAP use were obtained in 58% of these patients; EDS was reported by 47.2% of patients at baseline and by 30.3% at follow-up. Residual OSA, defined as an apnea-hypopnea index >10/h, and insufficient CPAP adherence, defined as nightly use <4 h, occurred with similar frequency in patients with and without EDS at follow-up. Prevalence of residual EDS was highest (40%) in patients with a first follow-up visit at 0-3 months, then it was 13-19% in patients with a first follow-up visit after 4 months to 2 years. The change in ESS (n = 2,190) was weakly correlated with CPAP use (R2 = 0.023, p < 0.0001). Logistic regression showed that an ESS score >10 at the first follow-up visit was associated directly with ESS at baseline and inversely with duration of follow-up, and CPAP use (R2 of the model: 0.417). EDS showed heterogeneity in different European countries both at baseline and at the first follow-up visit, suggesting modulation by cultural and lifestyle factors. In conclusion, residual EDS in CPAP-treated OSA occurred in approximately one in four patients at follow-up; its prevalence was highest (40%) in the first 3 months of treatment and subsequently decreased. The finding of residual EDS in a significant percentage of optimally treated OSA patients suggests that wake-promoting agents may be useful, but their indication should be evaluated after at least 3 months of treatment.