Positive Airway Pressure Adherence, Mortality, and Cardiovascular Events in Patients with Sleep Apnea

Assessment and management of continuous positive airway pressure therapy in patient with obstructive sleep apnea

Obstructive sleep apnea (OSA) causes excessive daytime sleepiness, impaired daytime functioning, and an increased risk of cardiovascular diseases. Continuous positive airway pressure (CPAP) is a highly effective therapy for moderate to severe OSA. Although CPAP adherence is commonly assessed using a 4-hthreshold, determining the optimal usage time based on clinical outcomes is crucial. While subjective sleepiness often improves with ≥4 h of CPAP usage, an extended duration (≥6 h) may be necessary to impact objective sleepiness. CPAP demonstrated a modest yet clinically meaningful dose-dependent effect on lowering blood pressure. For patients seeking antihypertensive benefits from CPAP therapy, the goal should extend beyond 4 h of use to maximize the therapeutic impact. Recognizing individual variations in sleep duration and responses to CPAP therapy is essential. The adoption of 'individualized goals for CPAP use,' outlining target times for specific outcomes, should also consider an individual's total sleep duration, including periods without CPAP. The impact of CPAP on clinical outcomes may vary, even with the same duration of CPAP use, depending on the period without CPAP use, particularly during the first or second half of sleep. Patients who remove or initiate CPAP midway or have a low CPAP usage frequency may require different forms of guidance. Tailoring patient education to address CPAP usage patterns may be necessary to enhanced satisfaction, self-efficacy, and adherence to therapy. Management of CPAP treatment should be personalized to meet individual needs and adapted based on specific response patterns for achieving treatment efficacy.

Heterogeneous Effects of Continuous Positive Airway Pressure in Non-Sleepy Obstructive Sleep Apnea on Cardiovascular Disease Outcomes: Post Hoc Machine Learning Analysis of the ISAACC Trial (ECSACT Study)

Rationale: Randomized controlled trials of continuous positive airway pressure (CPAP) therapy for cardiovascular disease (CVD) prevention among patients with obstructive sleep apnea (OSA) have been largely neutral. However, given that OSA is a heterogeneous disease, there may be unidentified subgroups demonstrating differential treatment effects. Objectives: We sought to apply a novel data-drive approach to identify nonsleepy OSA subgroups with heterogeneous effects of CPAP on CVD outcomes within the Impact of Sleep Apnea Syndrome in the Evolution of Acute Coronary Syndrome (ISAACC) study. Methods: Participants were randomly partitioned into two datasets. One for training (70%) our machine-learning model and a second (30%) for validation of significant findings. Model-based recursive partitioning was applied to identify subgroups with heterogeneous treatment effects. Survival analysis was conducted to compare treatment (CPAP vs. usual care [UC]) outcomes within subgroups. Results: A total of 1,224 nonsleepy OSA participants were included. Of 55 features entered into our model, only two appeared in the final model (i.e., average OSA event duration and hypercholesterolemia). Among participants at or below the model-derived average event duration threshold (19.5 s), CPAP was protective for a composite of CVD events (training hazard ratio [HR], 0.46; P = 0.002). For those with longer event duration (>19.5 s), an additional split occurred by hypercholesterolemia status. Among participants with longer event duration and hypercholesterolemia, CPAP resulted in more CVD events compared with UC (training HR, 2.24; P = 0.011). The point estimate for this harmful signal was also replicated in the testing dataset (HR, 1.83; P = 0.118). Conclusions: We discovered subgroups of nonsleepy OSA participants within the ISAACC study with heterogeneous effects of CPAP. Among the training dataset, those with longer OSA event duration and hypercholesterolemia had nearly 2.5 times more CVD events with CPAP compared with UC, whereas those with shorter OSA event duration had roughly half the rate of CVD events if randomized to CPAP.

National Implementation of CPAP Telemonitoring and a Pay-for-performance Scheme for Homecare Providers in France Leads to Prioritisation of Resources to Individuals with Low Therapy Adherence: The IMPACT-PAP Cohort Study

INTRODUCTION

Long-term adherence to continuous positive airway pressure (CPAP) therapy for obstructive sleep apnoea remains suboptimal and low adherence increases healthcare costs. This study investigated relationships between CPAP adherence and the intensity of support provided by homecare providers after implementation of telemonitoring and pay-for-performance reimbursement for CPAP in France.

METHODS

Adults who started CPAP in 2018/2019, used telemonitoring, and had ≥1 year of homecare provider data were eligible. The main objective was to determine associations between CPAP adherence at 1 month (low [<2h/night], intermediate [2 to <4h/night], high [≥4h/night]) and the number/type of homecare provider interactions (home visits, phone calls, mask change) during the first year.

RESULTS

Eleven thousand, one hundred sixty-six individuals were included (mean age 59.8±12.7 years, 67% male). The number of homecare provider interactions per person increased significantly as 1-month CPAP usage decreased (7.65±4.3, 6.5±4.0, 5.4±3.4 in low, intermediate and high adherence groups; p<0.01). There was marked improvement in device usage over the first 5-6 months of therapy in the low and intermediate adherence subgroups (p<0.05 after adjustment for age, sex, initial CPAP adherence, and number of interactions). After adjustment for age, sex and 1-month adherence, having 3-4 interactions was significantly associated with better 1-year adherence (odds ratio 1.24, 95% confidence interval 1.05-1.46), while having >7 interactions was significantly associated with worse 1-year adherence.

CONCLUSIONS

The telemonitoring/reimbursement scheme in France had a positive impact on CPAP adherence and facilitated a more personalised approach to therapy management, focusing resources on patients with low and intermediate adherence.

Long-term effects on clinical event, mental health, and related outcomes of CPAP for obstructive sleep apnea: a systematic review

STUDY OBJECTIVES

We performed a systematic review of long-term health outcomes of continuous positive airway pressure (CPAP) use in adults with obstructive sleep apnea.

METHODS

We updated prior systematic reviews with searches in multiple databases through January 3, 2023. We included randomized controlled trials (RCTs) and adjusted nonrandomized comparative studies that reported prespecified long-term (mostly > 1 year) health outcomes. We assessed risk of bias, conducted meta-analyses, and evaluated strength of evidence.

RESULTS

We found 38 eligible studies (16 trials, 22 observational). All conclusions were of low strength of evidence given study and data limitations. RCTs found no evidence of effect of CPAP on mortality (summary effect size [ES] 0.89; 95% confidence interval [CI] 0.66, 1.21); inclusion of adjusted nonrandomized comparative studies yields an association with reduced risk of death (ES 0.57; 95% CI 0.44, 0.73). RCTs found no evidence of effects of CPAP for cardiovascular death (ES 0.99; 95% CI 0.64, 1.53), stroke (ES 0.99; 95% CI 0.73, 1.35), myocardial infarction (ES 1.05; 95% CI 0.78, 1.41), incident atrial fibrillation (ES 0.89; 95% CI 0.48, 1.63), or composite cardiovascular outcomes (all statistically nonsignificant). RCTs found no evidence of effects for incident diabetes (ES 1.02; 95% CI 0.69, 1.51) or accidents (all nonsignificant) and no clinically significant effects on depressive symptoms, anxiety symptoms, or cognitive function.

CONCLUSIONS

Whether CPAP use for obstructive sleep apnea affects long-term health outcomes remains largely unanswered. RCTs and nonrandomized comparative studies are inconsistent regarding the effect of CPAP on mortality. Current studies are underpowered, with relatively short duration follow-up and methodological limitations.

CITATION

Balk EM, Adam GP, Cao W, Bhuma MR, D'Ambrosio C, Trikalinos TA. Long-term effects on clinical event, mental health, and related outcomes of CPAP for obstructive sleep apnea: a systematic review. J Clin Sleep Med. 2024;20(6):895-909.

The PAP-RES algorithm: Defining who, why and how to use positive airway pressure therapy for OSA

Obstructive sleep apnea (OSA) is a common condition that is increasing in prevalence worldwide. Untreated OSA has a negative impact on health-related quality of life and is an independent risk factor for cardiovascular diseases. Despite available data suggesting that cardiovascular risk might differ according to clinical phenotypes and comorbidities, current approaches to OSA treatment usually take a "one size fits all" approach. Identification of cardiovascular vulnerability biomarkers and clinical phenotypes associated with response to positive airway pressure (PAP) therapy could help to redefine the standard treatment paradigm. The new PAP-RES (PAP-RESponsive) algorithm is based on the identification of OSA phenotypes that are likely to impact therapeutic goals and modalities. The paradigm shift is to propose a simplified approach that defines therapeutic goals based on OSA phenotype: from a predominantly "symptomatic phenotype" (individuals with high symptom burden that negatively impacts on daily life and/or accident risk or clinically significant insomnia) to a "vulnerable cardiovascular phenotype" (individuals with comorbidities [serious cardiovascular or respiratory disease or obesity] that have a negative impact on cardiovascular prognosis or a biomarker of hypoxic burden and/or autonomic nervous system dysfunction). Each phenotype requires a different PAP therapy care pathway based on differing health issues and treatment objectives.

Effect of CPAP Treatment on Cardiovascular Outcomes

INTRODUCTION

Randomized controlled trials (RCT) have not demonstrated a role for continuous positive airway pressure (CPAP) on the secondary prevention of major cardiovascular events in obstructive sleep apnea (OSA) patients. However, participants in RCTs are substantially different from real-world patients. Therefore, we aimed to assess the effect of CPAP treatment on major cardiovascular events in real-world OSA patients.

METHODS

Population-based longitudinal observational study including all OSA patients with an active CPAP prescription at the beginning of 2011 in Catalonia, Spain, that terminated CPAP treatment during 2011 and did not have CPAP prescriptions between 2012-2015; and propensity-score-matched OSA patients that continued CPAP treatment until the end of 2015 or death. Adjusted hazard ratios were used to assess the association between CPAP treatment and overall and cardiovascular mortality, cardiovascular hospitalizations, or major adverse cardiovascular events (MACEs).

RESULTS

3638 CPAP terminators and 10,914 propensity-score-matched continuators were included (median age 67 [57-77] years, 71.4% male). During a median follow-up of 47.9 months CPAP continuators showed a lower risk of cardiovascular death than terminators (hazard ratio [HR]: 0.61; 95% confidence interval [CI]: 0.50-0.75) after adjusting by age, sex and key comorbidities. Similar results were found for cardiovascular hospitalizations (HR: 0.87; 95% CI: 0.76-0.99) and MACEs (HR: 0.84; 95% CI: 0.75-0.95).

CONCLUSION

CPAP treatment continuation could be associated with a significantly lower risk of major cardiovascular events in real-world OSA patients. This result highlights the importance of including real-world patients in studies on OSA.

The Future of Telemedicine for Obstructive Sleep Apnea Treatment: A Narrative Review

Obstructive sleep apnea is a common type of sleep-disordered breathing associated with multiple comorbidities. Nearly a billion people are estimated to have obstructive sleep apnea, which carries a substantial economic burden, but under-diagnosis is still a problem. Continuous positive airway pressure (CPAP) is the first-line treatment for OSAS. Telemedicine-based interventions (TM) have been evaluated to improve access to diagnosis, increase CPAP adherence, and contribute to easing the follow-up process, allowing healthcare facilities to provide patient-centered care. This narrative review summarizes the evidence available regarding the potential future of telemedicine in the management pathway of OSA. The potential of home sleep studies to improve OSA diagnosis and the importance of remote monitoring for tracking treatment adherence and failure and to contribute to developing patient engagement tools will be presented. Further studies are needed to explore the impact of shifting from teleconsultations to collaborative care models where patients are placed at the center of their care.

Adherence to continuous positive airway pressure therapy in patients with spinal cord injury and obstructive sleep apnea: trajectories and predictors

PURPOSE

To identify specific determinants of non-adherence or cessation of continuous positive airway pressure (CPAP) therapy in a population of patients with spinal cord injuries (SCI).

METHODS

Retrospective analysis of data from patients with SCI who underwent a full night supervised polysomnography between 2015 and 2021 and presented with moderate to severe obstructive sleep apnea (OSA) and for whom CPAP was indicated. Adherence was studied at 1, 6, and 12 months. Univariate and multivariate analyses were performed to identify factors associated with non-adherence (< 4 h per night or CPAP cessation). Factors studied were demographic and disease-related data and both subjective and objective sleep parameters.

RESULTS

A total of 60 patients were included (40% cervical SCI). In univariate analysis, the only predictive parameters of non-adherence observed at 1, 6, and 12 months were the average use of CPAP on the 1st night (p = 0.02) and over the 1st week (p ≤ 0.001). A complete lesion (AIS-A) was predictive of non-adherence at 1 and 6 months (p = 0.02 at 6 months), while mask leakage was associated with non-adherence at 12 months (p = 0.02). Upper limb autonomy and the presence of family caregivers did not appear to be protective. In multivariate analysis, only the average use in the first week remained predictive of adherence (> 4 h) in the short, medium and long term.

CONCLUSION

In patients with SCI and OSA, the 1st week of CPAP treatment seems to be determinant of short-, medium-, and long-term CPAP adherence. Support for SCI patients from the start of treatment is essential and may help avoid treatment failures.

Guidelines for the assessment and management of residual sleepiness in obstructive apnea-hypopnea syndrome: Endorsed by the French Sleep Research and Medicine Society (SFRMS) and the French Speaking Society of Respiratory Diseases (SPLF)

Excessive daytime sleepiness (EDS) is frequent among patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and can persist despite the optimal correction of respiratory events (apnea, hypopnea and respiratory efforts), using continuous positive airway pressure (CPAP) or mandibular advancement device. Symptoms like apathy and fatigue may be mistaken for EDS. In addition, EDS has multi-factorial origin, which makes its evaluation complex. The marketing authorization [Autorisation de Mise sur le Marché (AMM)] for two wake-promoting agents (solriamfetol and pitolisant) raises several practical issues for clinicians. This consensus paper presents recommendations of good clinical practice to identify and evaluate EDS in this context, and to manage and follow-up the patients. It was conducted under the mandate of the French Societies for sleep medicine and for pneumology [Société Française de Recherche et de Médecine du Sommeil (SFRMS) and Société de Pneumologie de Langue Française (SPLF)]. A management algorithm is suggested, as well as a list of conditions during which the patient should be referred to a sleep center or a sleep specialist. The benefit/risk balance of a wake-promoting drug in residual EDS in OSAHS patients must be regularly reevaluated, especially in elderly patients with increased cardiovascular and psychiatric disorders risks. This consensus is based on the scientific knowledge at the time of the publication and may be revised according to their evolution.

Identifying clusters of patient comorbidities associated with obstructive sleep apnea using electronic health records

STUDY OBJECTIVES

The objectives of this study were to understand the relative comorbidity burden of obstructive sleep apnea (OSA), determine whether these relationships were modified by sex or age, and identify patient subtypes defined by common comorbidities.

METHODS

Cases with OSA and noncases (controls) were defined using a validated electronic health record (EHR)-based phenotype and matched for age, sex, and time period of follow-up in the EHR. We compared prevalence of the 20 most common comorbidities between matched cases and controls using conditional logistic regression with and without controlling for body mass index. Latent class analysis was used to identify subtypes of OSA cases defined by combinations of these comorbidities.

RESULTS

In total, 60,586 OSA cases were matched to 60,586 controls (from 1,226,755 total controls). Patients with OSA were more likely to have each of the 20 most common comorbidities compared with controls, with odds ratios ranging from 3.1 to 30.8 in the full matched set and 1.3 to 10.2 after body mass index adjustment. Associations between OSA and these comorbidities were generally stronger in females and patients with younger age at diagnosis. We identified 5 distinct subgroups based on EHR-defined comorbidities: High Comorbidity Burden, Low Comorbidity Burden, Cardiovascular Comorbidities, Inflammatory Conditions and Less Obesity, and Inflammatory Conditions and Obesity.

CONCLUSIONS

Our study demonstrates the power of leveraging the EHR to understand the relative health burden of OSA, as well as heterogeneity in these relationships based on age and sex. In addition to enrichment for comorbidities, we identified 5 novel OSA subtypes defined by combinations of comorbidities in the EHR, which may be informative for understanding disease outcomes and improving prevention and clinical care. Overall, this study adds more evidence that OSA is heterogeneous and requires personalized management.

CITATION

Te TT, Keenan BT, Veatch OJ, Boland MR, Hubbard RA, Pack AI. Identifying clusters of patient comorbidities associated with obstructive sleep apnea using electronic health records. J Clin Sleep Med. 2024;20(4):521-533.

ERS International Congress 2023: highlights from the Sleep Disordered Breathing Assembly

The topic of sleep-related breathing disorders is always evolving, and during the European Respiratory Society (ERS) International Congress 2023 in Milan, Italy, the latest research and clinical topics in respiratory medicine were presented. The most interesting issues included new diagnostic tools, such as cardiovascular parameters and artificial intelligence, pathophysiological traits of sleep disordered breathing from routine polysomnography or polygraphy signals, and new biomarkers and the diagnostic approach in patients with excessive daytime sleepiness. This article summarises the most relevant studies and topics presented at the ERS International Congress 2023. Each section has been written by early career members of ERS Assembly 4.

Large variability in definitions of sleep apnea indices used in clinical studies

STUDY OBJECTIVES

We explored the variability of sleep apnea indices and definitions of obstructive sleep apnea in clinical studies of continuous positive airway pressure.

METHODS

In a systematic review of the long-term clinical effects of continuous positive airway pressure, we noted variability across studies in how sleep apnea was defined. We, thus, sought to quantify the heterogeneity.

RESULTS

Across 57 comparative studies of long-term clinical outcomes of continuous positive airway pressure, only 40% fully and explicitly reported their definitions of apnea and hypopnea. Most studies defined apnea as 100% airflow cessation, but a minority used 90% or even down to 75% thresholds. Almost half of the studies defined hypopnea as ≥ 50% airflow cessation, but the majority used 30% or even 25% thresholds. Similarly, about half of the studies used a 4% desaturation threshold to define oxygen desaturation and about half used a 3% threshold, with 2 studies using both thresholds for different purposes. Randomized trials were no more consistent or better-reported than observational studies. Studies that cited published criteria generally reported definitions that were different from the cited criteria.

CONCLUSIONS

The criteria used to define sleep apnea indices (apnea, hypopnea, and oxygen desaturation) were highly variable, even among studies stating that definitions were based on the same standard criteria. It was often difficult to discern the actual criteria used. The great variability across studies and lack of transparency about their sleep study methods hampers the interpretability and utility of the studies and calls into question whether studies are generalizable from one setting to another.

CITATION

Balk EM, Adam GP, D'Ambrosio CM. Large variability in definitions of sleep apnea indices used in clinical studies. J Clin Sleep Med. 2024;20(3):461-468.

Approach the Patient With Obstructive Sleep Apnea and Obesity

Obstructive sleep apnea (OSA) and obesity are highly prevalent and bidirectionally associated. OSA is underrecognized, however, particularly in women. By mechanisms that overlap with those of obesity, OSA increases the risk of developing, or having poor outcomes from, comorbid chronic disorders and impairs quality of life. Using 2 illustrative cases, we discuss the relationships between OSA and obesity with type 2 diabetes, dyslipidemia, cardiovascular disease, cognitive disturbance, mood disorders, lower urinary tract symptoms, sexual function, and reproductive disorders. The differences in OSA between men and women, the phenotypic variability of OSA, and comorbid sleep disorders are highlighted. When the probability of OSA is high due to consistent symptoms, comorbidities, or both, a diagnostic sleep study is advisable. Continuous positive airway pressure or mandibular advancement splints improve symptoms. Benefits for comorbidities are variable depending on nightly duration of use. By contrast, weight loss and optimization of lifestyle behaviors are consistently beneficial.

Loop Gain as a Predictor of Blood Pressure Response in Patients Treated for Obstructive Sleep Apnea: Secondary Analysis of a Clinical Trial

Rationale: Randomized trials have shown inconsistent cardiovascular benefits from obstructive sleep apnea (OSA) therapy. Intermittent hypoxemia can increase both sympathetic nerve activity and loop gain ("ventilatory instability"), which may thus herald cardiovascular treatment benefit. Objectives: To test the hypothesis that loop gain predicts changes in 24-hour mean blood pressure (MBP) in response to OSA therapy and compare its predictive value against that of other novel biomarkers. Methods: The HeartBEAT (Heart Biomarker Evaluation in Apnea Treatment) trial assessed the effect of 12 weeks of continuous positive airway pressure (CPAP) versus oxygen versus control on 24-hour MBP. We measured loop gain and hypoxic burden from sleep tests and identified subjects with a sleepy phenotype using cluster analysis. Associations between biomarkers and 24-h MBP were assessed in the CPAP/oxygen arms using linear regression models adjusting for various covariates. Secondary outcomes and predictors were analyzed similarly. Results: We included 93 and 94 participants in the CPAP and oxygen arms, respectively. Overall, changes in 24-hour MBP were small, but interindividual variability was substantial (mean [standard deviation], -2 [8] and 1 [8] mm Hg in the CPAP and oxygen arms, respectively). Higher loop gain was significantly associated with greater reductions in 24-hour MBP independent of covariates in the CPAP arm (-1.5 to -1.9 mm Hg per 1-standard-deviation increase in loop gain; P ⩽ 0.03) but not in the oxygen arm. Other biomarkers were not associated with improved cardiovascular outcomes. Conclusions: To our knowledge, this is the first study suggesting that loop gain predicts blood pressure response to CPAP therapy. Eventually, loop gain estimates may facilitate patient selection for research and clinical practice. Clinical trial registered with www.clinicaltrials.gov (NCT01086800).

Heterogeneity of obstructive sleep apnea phenotypes after ischemic stroke: Outcome variation by cluster analysis

INTRODUCTION

Obstructive sleep apnea (OSA) is common but under-recognized after stroke. The aim of this study was to determine whether post-stroke phenotypic OSA subtypes are associated with stroke outcome in a population-based observational cohort.

METHODS

Ischemic stroke patients (n = 804) diagnosed with OSA (respiratory event index ≥10) soon after ischemic stroke were identified from the Brain Attack Surveillance in Corpus Christi (BASIC) project. Functional, cognitive, and quality of life outcomes were assessed at 90 days post-stroke and long-term stroke recurrence was ascertained. Latent profile analysis was performed based on demographic and clinical features, pre-stroke sleep characteristics, OSA severity, and vascular risk factors. Regression models were used to assess the association between phenotypic clusters and outcomes.

RESULTS

Four distinct phenotypic clusters provided the best fit. Cluster 1 was characterized by more severe stroke; cluster 2 by severe OSA and higher prevalence of medical comorbidities; cluster 3 by mild stroke and mild OSA; and cluster 4 by moderate OSA and mild stroke. Compared to cluster 3 and after adjustment for baseline stroke severity, cluster 1 and cluster 2 had worse 90-day functional outcome and cluster 1 also had worse quality of life. No difference in cognitive outcome or stroke recurrence rate was noted by cluster.

CONCLUSION

Post-stroke OSA is a heterogeneous disorder with different clinical phenotypes associated with stroke outcomes, including both daily function and quality of life. The unique presentations of OSA after stroke may have important implications for stroke prognosis and personalized treatment strategies.

Sleep disordered breathing assessment in patient with slowly progressive neuromuscular disease

BACKGROUND

Sleep-disordered breathing (SDB) is common in patients with neuromuscular diseases (NMD). Focusing on hypercapnia may lead to the neglect of other SDB such as obstructive and/or central sleep apnea syndrome (SAS). Our objectives were to assess the risk of inappropriate SDB management according to different screening strategies and to evaluate the prevalence and determinants of isolated and overlapping sleep apnea in patients with slowly progressive NMD.

METHODS

This monocentric, cross-sectional, retrospective study analyzed medical records of adult NMD patients referred to a sleep department. Diagnostic strategies, including respiratory polygraphy (RP), nocturnal transcutaneous capnography (tcCO2), and blood gases (BG), were assessed for their performance in diagnosing SDB. Demographics and pulmonary function test results were compared between patients with or without SDB to identify predictors.

RESULTS

Among the 149 patients who underwent a full diagnostic panel (RP + tcCO2 + BG), 109 were diagnosed with SDB. Of these, 33% had isolated SAS, and central apneas were predominant. Using single diagnostic strategies would lead to inappropriate SDB management in two thirds of patients. A combination of 2 diagnostic tools resulted respectively in 21.1, 22.9 and 42.2 % of inappropriate SDB management for RP + tcCO2, RP + BG and tcCO2 + BG.

CONCLUSION

The significant prevalence of sleep apnea syndrome in patients with slowly progressive NMD highlights the need for increased awareness among clinicians. Improved diagnostics involve a systematic approach addressing both sleep apnea and diurnal and nocturnal alveolar hypoventilation to avoid inappropriate management and limit the consequences of SDB.

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.

Positive airway pressure therapy adherence and outcomes in obstructive sleep apnea: An exploratory longitudinal retrospective randomized chart review

Background

Positive airway pressure (PAP) therapy is prescribed to patients with obstructive sleep apnea (OSA). A commonly used definition for PAP therapy adherence is based upon the minimum requirements to receive Medicare coverage in the US, defined as PAP usage of four or more hours per night on 70 percent of nights for at least 30 consecutive days. However, little evidence exists to support this definition for PAP therapy adherence. Therefore, the present study sought to determine the efficacy of the present definition of PAP therapy adherence on longitudinal outcomes in patients with OSA, using objectively measured PAP device usage time.

Methods

An exploratory longitudinal, retrospective, randomized chart review was done to assess clinical outcomes between patients with OSA who were defined as PAP therapy adherent (n=50) and non-adherent (n=50) during an eight-year observation period.

Results

No significant differences were shown between groups for mortality, hospitalizations, or development of co-morbidities during the observation period. However, logistic regression showed significantly higher odds of adherence in male patients compared to female patients (OR=8.519; 95%CI=1.301-55.756; p=0.025) and significantly lower odds of adherence in patients with higher normal (OR=0.039; 95%CI=0.005-0.392; p=0.003), mild excessive (OR=0.039; 95%CI=0.003-0.517; p=0.014), and severe excessive (OR=0.088; 95%CI=0.012-0.635; p=0.016) daytime sleepiness compared to patients with lower normal daytime sleepiness. An increasing number of hospitalizations also corresponded with a significant decrease in odds of being adherent (OR=0.741; 95%CI=0.551-0.995; p=0.046).

Conclusion

The present study supports a steadily growing body of literature calling for more consideration and evidence to support a definition of PAP therapy adherence that is clinically meaningful.

FACE study: 2-year follow-up of adaptive servo-ventilation for sleep-disordered breathing in a chronic heart failure cohort

BACKGROUND

Sleep-disordered breathing (SDB) is a common comorbidity in patients with heart failure (HF) and is associated with worse prognosis.

OBJECTIVES

This study evaluated the effects of adaptive servo-ventilation (ASV) on morbidity and mortality in a large heterogeneous population of HF patients with different etiologies/phenotypes.

METHODS

Consecutive HF patients with predominant central sleep apnea (± obstructive sleep apnea) indicated for ASV were included; the control group included patients who refused or stopped ASV before three months follow-up. Six homogenous clusters were determined using the latent class analysis (LCA) method. The primary endpoint was time to composite first event (all-cause death, lifesaving cardiovascular intervention, or unplanned hospitalization for worsening of chronic HF).

RESULTS

Of 503 patients at baseline, 324 underwent 2-year follow-up. Compared to control group, 2-year primary endpoint event-free survival was significantly greater in patients in ASV group only in univariable analysis (1.67, 95% [1.12-2.49]; p = 0.01). Secondary endpoints, event-free of cardiovascular death or heart failure-related hospitalization and all-cause death or all-cause hospitalization were positively impacted by ASV (univariate and multivariable analysis). LCA identified two groups, with preserved and mid-range left ventricular ejection fraction (LVEF) and severe hypoxia, in whom ASV increase prognosis benefit.

CONCLUSIONS

Patients with HF and SDB are a highly heterogeneous group identified using LCA. Systematic deep phenotyping is essential to ensure that ASV is prescribed to those benefit from therapy, as ASV use in patients with severe hypoxic burden and those with HFpEF was associated with a significant reduction in cardiovascular events and mortality.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT01831128.

Incident Coronary Calcium Score in Patients With OSA With and Without Excessive Sleepiness: Brazilian Longitudinal Study of Adult Health

BACKGROUND

Uncertainty exists about the impact of OSA and its phenotypes on cardiovascular disease.

RESEARCH QUESTION

Are OSA and clinical features such as daytime sleepiness associated with incident subclinical coronary atherosclerosis?

STUDY DESIGN AND METHODS

In this prospective community-based cohort study, we administered a sleepiness questionnaire, actigraphy, and home sleep studies at baseline. Coronary artery calcium (CAC; 64-slice multidetector CT scan imaging) was measured at two different time points throughout the study (baseline, between 2010 and 2014, and follow-up, between 2016 and 2018). Incidence of subclinical atherosclerosis was defined as baseline CAC of 0 followed by CAC of > 0 at a 5-year follow-up visit. The association of incident CAC outcome was assessed using logistic regression. Stratified analyses based on excessive daytime sleepiness (EDS) were performed.

RESULTS

We analyzed 1,956 participants with available CAC scores at baseline (mean age, 49 ± 8 years; 57.9% female; 32.4% with OSA). In covariate-adjusted analyses (n = 1,247; mean follow-up, 5.1 ± 0.9 years), we found a significant association between OSA and incidence of subclinical atherosclerosis (OR, 1.26; 95% CI, 1.06-1.48), with stronger effects among those reporting EDS (OR, 1.66; 95% CI, 1.30-2.12; P = .028 for interaction). Interestingly, EDS per se was not associated with any CAC outcome. An exploratory analysis of the square root of CAC progression (baseline CAC > 0 followed by a numerical increase in scores at follow-up; n = 319) showed a positive association for both OSA (β = 1.084; 95% CI, 0.032-2.136; P = .043) and OSA with EDS (β = 1.651; 95% CI, 0.208-3.094; P = .025).

INTERPRETATION

OSA, particularly with EDS, predicts the incidence and progression of CAC. These results support biological plausibility for the increased cardiovascular risk observed among patients with OSA with excessive sleepiness.

Long-term health outcomes for patients with obstructive sleep apnea: placing the Agency for Healthcare Research and Quality report in context-a multisociety commentary

This multisociety commentary critically examines the Agency for Healthcare Research and Quality (AHRQ) final report and systematic review on long-term health outcomes in obstructive sleep apnea. The AHRQ report was commissioned by the Centers for Medicare & Medicaid Services and particularly focused on the long-term patient-centered outcomes of continuous positive airway pressure, the variability of sleep-disordered breathing metrics, and the validity of these metrics as surrogate outcomes. This commentary raises concerns regarding the AHRQ report conclusions and their potential implications for policy decisions. A major concern expressed in this commentary is that the AHRQ report inadequately acknowledges the benefits of continuous positive airway pressure for several established, long-term clinically important outcomes including excessive sleepiness, motor vehicle accidents, and blood pressure. While acknowledging the limited evidence for the long-term benefits of continuous positive airway pressure treatment, especially cardiovascular outcomes, as summarized by the AHRQ report, this commentary reviews the limitations of recent randomized controlled trials and nonrandomized controlled studies and the challenges of conducting future randomized controlled trials. A research agenda to address these challenges is proposed including study designs that may include both high quality randomized controlled trials and nonrandomized controlled studies. This commentary concludes by highlighting implications for the safety and quality of life for the millions of people living with obstructive sleep apnea if the AHRQ report alone was used by payers to limit coverage for the treatment of obstructive sleep apnea while not considering the totality of available evidence.

CITATION

Patil SP, Billings ME, Bourjeily G, et al. Long-term health outcomes for patients with obstructive sleep apnea: placing the Agency for Healthcare Research and Quality report in context-a multisociety commentary. J Clin Sleep Med. 2024;20(1):135-149.

New insights and potential clinical implications of the odds ratio product

The odds ratio product (ORP) is a continuous metric of sleep depth that ranges from 0 (very deep sleep) to 2. 5 (full wakefulness). Its advantage over the conventional method recommended by AASM is that it discloses different levels of stage wake (sleep propensity) and different sleep depths within the same sleep stage. As such, it can be used to identify differences in sleep depth between subjects, and in the same subjects under different circumstances, when differences are not discernible by conventional staging. It also identifies different sleep depths within stage rapid-eye-movement sleep, with possible implications to disorders during this stage. Epoch-by-epoch ORP can be displayed graphically across the night or as average values in conventional sleep stages. In addition, ORP can be reported as % of recording time in specific ORP ranges (e.g., deciles of the total ORP range) where it produces distinct distribution patterns (ORP-architecture) that have been associated with different clinical disorders and outcomes. These patterns offer unique research opportunities to identify different mechanisms and potential therapy for various sleep complaints and disorders. In this review I will discuss how ORP is measured, its validation, differences from delta power, and the various phenotypes, and their postulated mechanisms, identified by ORP architecture and the opportunities for research to advance management of sleep-disordered breathing, insomnia and idiopathic hypersomnia.

Sleep and Breathing Conference highlights 2023: a summary by ERS Assembly 4

This paper presents some of the highlights of the Sleep and Breathing Conference 2023 https://bit.ly/46MxJml.

Creating an Optimal Approach for Diagnosing Sleep Apnea

Sleep apnea is nowadays recognized as a treatable chronic disease and awareness of it has increased, leading to an upsurge in demand for diagnostic testing. Conventionally, diagnosis depends on overnight polysomnography in a sleep clinic, which is highly human-resource intensive and ignores the night-to-night variability in classical sleep apnea markers, such as the apnea-hypopnea index. In this review, the authors summarize the main improvements that could be made in the sleep apnea diagnosis strategy; how technological innovations and multi-night home testing could be used to simplify, increase access, and reduce costs of diagnostic testing while avoiding misclassification of severity.

Unmasking Heterogeneity of Sleep Apnea

Sleep apnea is heterogeneous in multiple dimensions. There are different physiological risk factors that may have clinical relevance. However, assessing them is challenging. An approach to ascertain them using a simple model of ventilatory control has been proposed. It is based, however, on untenable assumptions. There are limited validation data and reproducibility is not stellar. There are also different symptom subtypes. They have been found in multiple population-based and clinical cohorts worldwide. Symptomatic benefit from therapy is most marked in the excessively sleepy subtype. This group may also be the group at increased CV risk from obstructive sleep apnea.

Obstructive sleep apnoea heterogeneity and cardiovascular disease

Obstructive sleep apnoea (OSA), characterized by recurrent periods of upper airway obstruction and intermittent hypoxaemia, is prevalent in patients with cardiovascular disease (CVD), and is therefore important to consider in the prevention and management of CVD. Observational studies indicate that OSA is a risk factor for incident hypertension, poorly controlled blood pressure, stroke, myocardial infarction, heart failure, cardiac arrhythmias, sudden cardiac death and all-cause death. However, clinical trials have not provided consistent evidence that treatment with continuous positive airway pressure (CPAP) improves cardiovascular outcomes. These overall null findings might be explained by limitations in trial design and low levels of adherence to CPAP. Studies have also been limited by the failure to consider OSA as a heterogeneous disorder that consists of multiple subtypes resulting from variable contributions from anatomical, physiological, inflammatory and obesity-related risk factors, and resulting in different physiological disturbances. Novel markers of sleep apnoea-associated hypoxic burden and cardiac autonomic response have emerged as predictors of OSA-related susceptibility to adverse health outcomes and treatment response. In this Review, we summarize our understanding of the shared risk factors and causal links between OSA and CVD and emerging knowledge on the heterogeneity of OSA. We discuss the varied mechanistic pathways that result in CVD that also vary across subgroups of OSA, as well as the potential role of new biomarkers for CVD risk stratification.

Investigating associations between social determinants, self-efficacy measurement of sleep apnea and CPAP adherence: the SEMSA study

Study objectives

The prospective Self-Efficacy Measure for Sleep Apnea study (SEMSAS) is investigating thresholds for health literacy, self-efficacy and precariousness at obstructive sleep apnea (OSA) diagnosis to predict CPAP adherence. This paper describes the study protocol and presents baseline data from the ongoing study.

Methods

Eligible individuals had confirmed OSA and were referred to a homecare provider for continuous positive airway pressure (CPAP) therapy initiation. Data on patient characteristics and comorbidities were collected, along with baseline evaluations of self-efficacy [15-item Self-Efficacy Measure for Sleep Apnea tool (SEMSA-15)], precariousness [Deprivation in Primary Care Questionnaire (DipCareQ)], and health literacy (Health Literacy Questionnaire). CPAP adherence over 12 months of follow-up will be determined using remote monitoring of CPAP device data. The primary objective is to define an optimal SEMSA-15 score threshold to predict CPAP adherence at 3- and 12-month follow-up.

Results

Enrollment of 302 participants (71% male, median age 55 years, median body mass index 31.6 kg/m²) is complete. Low self-efficacy (SEMSA-15 score ≤ 2.78) was found in 93/302 participants (31%), and 38 (12.6%) reported precariousness (DipCareQ score > 1); precariousness did not differ significantly between individuals with a SEMSA-15 score ≤ 2.78 versus >2.78. Health literacy was generally good, but was significantly lower in individuals with versus without precariousness, and with low versus high self-efficacy.

Conclusion

SEMSAS is the first study using multidimensional baseline assessment of self-efficacy, health literacy and precariousness, plus other characteristics, to determine future adherence to CPAP, including CPAP adherence trajectories. Collection of follow-up data is underway.

Strategies to Assess the Effect of Continuous Positive Airway Pressure on Long-Term Clinically Important Outcomes among Patients with Symptomatic Obstructive Sleep Apnea: An Official American Thoracic Society Workshop Report

Continuous positive airway pressure (CPAP) is the first-line treatment for obstructive sleep apnea (OSA). Although CPAP improves symptoms (e.g., daytime sleepiness), there is a lack of high-quality evidence that CPAP prevents many long-term outcomes, including cognitive impairment, myocardial infarction, and stroke. Observational studies suggest that patients with symptoms may be particularly likely to experience these preventive benefits with CPAP, but ethical and practical concerns limited the participation of such patients in prior long-term randomized trials. As a result, there is uncertainty about the full benefits of CPAP, and resolving this uncertainty is a key priority for the field. This workshop assembled clinicians, researchers, ethicists, and patients to identify strategies to understand the causal effects of CPAP on long-term clinically important outcomes among patients with symptomatic OSA. Quasi-experimental designs can provide valuable information and are less time and resource intensive than trials. Under specific conditions and assumptions, quasi-experimental studies may be able to provide causal estimates of CPAP's effectiveness from generalizable observational cohorts. However, randomized trials represent the most reliable approach to understanding the causal effects of CPAP among patients with symptoms. Randomized trials of CPAP can ethically include patients with symptomatic OSA, as long as there is outcome-specific equipoise, adequate informed consent, and a plan to maximize safety while minimizing harm (e.g., monitoring for pathologic sleepiness). Furthermore, multiple strategies exist to ensure the generalizability and practicality of future randomized trials of CPAP. These strategies include reducing the burden of trial procedures, improving patient-centeredness, and engaging historically excluded and underserved populations.

The individual and societal price of non-adherence to continuous positive airway pressure, contributors and strategies for improvement

INTRODUCTION

Continuous positive airway pressure (CPAP) is the first line therapy for obstructive sleep apnea (OSA). CPAP is highly effective for improving symptoms and quality of life but the major issue is adherence, with up to 50% of OSA discontinuing CPAP in the first 3 years after CPAP initiation.

AREAS COVERED

We present the individual and societal cost of non-adherence to CPAP, factors associated with non-adherence to CPAP, as well as current strategies for improving adherence including telehealth, couples-based interventions and behavioral interventions. We also report on challenges and pitfalls for the visualization and analysis of CPAP remote monitoring platforms.

EXPERT OPINION

CPAP termination rates and adherence to therapy remain major issues despite technical improvements in CPAP devices. The individual and societal price of non-adherence to CPAP for OSA patients goes beyond excessive sleepiness and includes cardiovascular events, all-cause mortality, and increased health costs. Strategies for improving CPAP adherence should be individually tailored and aim to also improve lifestyle habits including physical activity and nutrition. Access to these strategies should be supported by refining visualization dashboards of CPAP remote monitoring platforms, and by disseminating telehealth and innovative analytics, including artificial intelligence.

Utilization of the GOAL questionnaire as a standardized screening tool for obstructive sleep apnea

The purpose of our study was to evaluate the application value of the GOAL questionnaire in screening obstructive sleep apnea (OSA) and to compare it with the other three questionnaires in sleep clinics. A cross-sectional study was conducted in 436 patients who had undergone nocturnal polysomnography in the sleep unit of the First Hospital of Shanxi Medical University between September 2021 and May 2022, and all patients completed the four questionnaires (GOAL questionnaire, STOP-Bang questionnaire, NoSAS score and No-Apnea score) truthfully, and the patients were divided into 3 groups: AHI ≥ 5 events/h group, AHI ≥ 15 events/h group and AHI ≥ 30 events/h group. The predictive effect of the questionnaire on different AHI cut-off values was calculated, and performance of four questionnaires was assessed by the discriminatory ability. This study ultimately included 410 patients, and there were statistically significant differences in gender, age, BMI, neck circumference, clinical symptoms, hypertension, diabetes, AHI, and minimum oxygen saturation between OSA and non-OSA groups (P < 0.05). The AUC for No-Apnea score was 0.79, the AUC for STOP-Bang questionnaire was 0.86, the AUC for NoSAS score was 0.81, and the AUC for GOAL questionnaire was 0.77. These four questionnaires were effective in screening OSA when AHI ≥ 15 events/h. Similar to No-Apnea score, STOP-Bang score and NoSAS score, GOAL questionnaire has a good predictive value for OSA, which is a questionnaire suitable for primary health-care centers and clinics.

Contemporary Concise Review 2022: Sleep

COVID-19 AND SLEEP: The COVID-19 pandemic is associated with an increase in insomnia and impaired sleep quality Health care workers are particularly susceptible and improved with cognitive behavioural therapy for insomnia (CBT-I) Long COVID has significant effects on sleep OSA impacts on the severity of acute COVID-19 illness OBSTRUCTIVE SLEEP APNOEA: Large trials of clinically representative patients confirm the cardiovascular benefits of CPAP treatment in OSA CPAP may improve long-term cognitive outcomes in OSA, but further research is needed Racial disparities in OSA prevalence and mortality risk are becoming evident Periodic evaluation of OSA risk in pregnancy is important as timing may be key for intervention to prevent or treat cardiovascular risk factors INSOMNIA: Comorbid insomnia and obstructive sleep apnoea (COMISA) can frequently co-exist and the combined negative effects of both may be deleterious, particularly to cardiovascular health There is evidence for effectiveness with novel orexin receptor antagonists.

Impact of a telerehabilitation programme combined with continuous positive airway pressure on symptoms and cardiometabolic risk factors in obstructive sleep apnea patients

Background

Obstructive sleep apnea syndrome is a common sleep-breathing disorder associated with adverse health outcomes including excessive daytime sleepiness, impaired quality of life and is well-established as a cardiovascular risk factor. Continuous positive airway pressure is the reference treatment, but its cardiovascular and metabolic benefits are still debated. Combined interventions aiming at improving patient's lifestyle behaviours are recommended in guidelines management of obstructive sleep apnea syndrome but adherence decreases over time and access to rehabilitation programmes is limited. Telerehabilitation is a promising approach to address these issues, but data are scarce on obstructive sleep apnea syndrome.

Methods

The aim of this study is to assess the potential benefits of a telerehabilitation programme implemented at continuous positive airway pressure initiation, compared to continuous positive airway pressure alone and usual care, on symptoms and cardiometabolic risk factors of obstructive sleep apnea syndrome. This study is a 6-months multicentre randomized, parallel controlled trial during which 180 obese patients with severe obstructive sleep apnea syndrome will be included. We will use a sequential hierarchical criterion for major endpoints including sleepiness, quality of life, nocturnal systolic blood pressure and inflammation biological parameters.

Discussion

m-Rehab obstructive sleep apnea syndrome is the first multicentre randomized controlled trial to examine the effectiveness of a telerehabilitation lifestyle programme in obstructive sleep apnea syndrome. We hypothesize that a telerehabilitation lifestyle intervention associated with continuous positive airway pressure for 6 months will be more efficient than continuous positive airway pressure alone on symptoms, quality of life and cardiometabolic risk profile. Main secondary outcomes include continuous positive airway pressure adherence, usability and satisfaction with the telerehabilitation platform and medico-economic evaluation.

Trial registration

Clinicaltrials.gov Identifier: NCT05049928. Registration data: 20 September 2021.