Mortality and morbidity in obstructive sleep apnoea-hypopnoea syndrome: results from a 30-year prospective cohort study

Interrelationship Between Obstructive Sleep Apnea Syndrome and Small Airway Disease: A Comprehensive Review

Study Objectives: This review aims to explore the epidemiology, pathophysiology, risk factors, and diagnostic approaches of obstructive sleep apnea syndrome and small airway disease, emphasizing their interrelationship and implications for clinical management. Methods: A comprehensive analysis of the literature was conducted to examine shared and distinct characteristics of obstructive sleep apnea syndrome and small airway disease. Risk factors, clinical presentations, diagnostic tools, and management strategies were reviewed to identify potential areas for improvement in care. Results: Obstructive sleep apnea syndrome, characterized by intermittent upper airway obstruction during sleep, contributes to fragmented sleep and systemic diseases. Small airway disease involves inflammation and obstruction of the small airways, impairing airflow and gas exchange. Shared risk factors, such as obesity, smoking, and age, were identified as contributors to the development and progression of both conditions. The co-occurrence of obstructive sleep apnea syndrome and small airway disease exacerbates respiratory symptoms and increases the risk of comorbidities, such as pulmonary hypertension, heart failure, and respiratory failure. Recognition of their interplay highlights the need for integrated diagnostic and therapeutic strategies. Conclusions: The interrelationship between obstructive sleep apnea syndrome and small airway disease underscores the importance of integrated management approaches to improve patient outcomes. Addressing shared risk factors and understanding the interplay between these conditions are crucial for optimizing care. This review identifies key knowledge gaps, including the need for precise diagnostic tools and targeted therapies, which are essential for advancing personalized treatment strategies for individuals with obstructive sleep apnea syndrome and small airway disease.

Evaluating the Benefit of Home Support Provider Services for Positive Airway Pressure Therapy in Patients With Obstructive Sleep Apnea: Protocol for an Ambispective International Real-World Study

BACKGROUND

Adherence and persistence to positive airway pressure (PAP) therapy are key factors for positive health outcomes. Home support providers participate in the home implementation and follow-up of PAP therapy for patients with obstructive sleep apnea (OSA). In Europe, home support provider service levels are country (or area) specific, resulting in differences in content and frequency of patient interactions. However, no robust evaluation of the impact of these differences on clinical and patient outcomes has been performed.

OBJECTIVE

The AWAIR study aims to evaluate and compare the impact of different home support provider service levels on PAP adherence and persistence in 4 European countries.

METHODS

This real-world, ambispective, cohort study-conducted in France, Belgium, Spain, and Portugal-will recruit adults with OSA who started PAP therapy between 2019 and 2023 and were followed by an Air Liquide Healthcare home support provider. Given the large number of eligible participants (around 150,000), the study will use a decentralized and digital approach. A patient video will present the study objectives and the participation process. A secure electronic solution will be used to manage patient information and consent, as well as to administer a web-based questionnaire. Retrospective data, collected during routine patient follow-up by home support providers, include the level of service and device data, notably PAP use. Prospective data collected using an electronic patient-reported outcome tool include health status, OSA-related factors, patient-reported outcomes including quality of life and symptoms, OSA and PAP literacy, patient-reported experience, and satisfaction with PAP therapy and service. Hierarchical models, adjusted for preidentified confounding factors, will be used to assess the net effect of home support provider services on PAP adherence and persistence while minimizing real-world study biases and considering the influence of country-level contextual factors. We hypothesize that higher levels of home support provider services will be positively associated with adherence and persistence to PAP therapy.

RESULTS

As of December 2024, the study has received approval in France, Portugal, and 2 regions of Spain. The study began enrollment in France in October 2024. Results are expected in the second quarter of 2025.

CONCLUSIONS

The AWAIR study has a unique design, leveraging an unprecedented number of eligible participants, decentralized technologies, and a real-world comparative methodology across multiple countries. This approach will highlight intercountry differences in terms of patient characteristics, PAP adherence, and persistence, as well as patient-reported outcomes, patient-reported experiences, and satisfaction with the home service provider. By assessing the added value of home support provider services, the results will support best practices for patient management and for decision-making by payers and authorities.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/65840.

Smoking History and Nicotine Dependence Alter Sleep Features in Patients with Obstructive Sleep Apnea-Hypopnea Syndrome

Introduction: There are many aspects in the relationship between smoking and sleep that have not been investigated thoroughly yet, especially in regards to obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods: In this cross-sectional study, 2359 participants, who have visited the sleep clinic of our hospital during a 13-year period and were former or current smokers, were included. Their smoking history, measured in packyears of smoking, and their nicotine dependence, measured with the Fagerström scale, were correlated with various epidemiological and sleep-related variables. Results: Patients with respiratory, cardiovascular and metabolic comorbidities were older, more obese and presented a significantly greater history in packyears of smoking. Packyears were positively correlated with the Epworth sleepiness scale (ESS) (r = 0.06, p = 0.007), with %REM sleep time (r = 0.19, p = 0.042), apnea-hypopnea index (AHI) (r = 0.10, p < 0.001), oxygen desaturation index (ODI) (r = 0.10, p < 0.001), mean and maximum apnea duration (r = 0.10, p < 0.001 and r = 0.11, p < 0.001, respectively), while they were negatively correlated with mean and minimum SaO2 (r = -0.18, p < 0.001 and r = -0.13, p < 0.001, respectively). Furthermore, smoking history exhibited a significantly increasing trend with increasing OSA diagnosis and severity (p < 0.001). Patients with abnormal movements during sleep and those with restless sleep showed a significantly higher nicotine dependence, measured with the Fagerström scale, compared to those without abnormal movements or restless sleep (5.4 ± 2.8 vs. 4.7 ± 2.8, p = 0.002 and 5.1 ± 2.9 vs. 4.7 ± 2.7, p = 0.043). Conclusions: Smoking history in packyears probably affects OSAHS characteristics, while nicotine dependence seems to be related more with abnormal sleep behaviors.

Are noradrenergics combined with antimuscarinics the future pharmacologic treatment for obstructive sleep apnea? A systematic review and meta-analysis of randomized controlled trials

PURPOSE

Noradrenergics and antimuscarinics have been proposed as future pharmacotherapy for obstructive sleep apnea (OSA). However, the available randomized controlled trials (RCTs) showed heterogeneous results regarding the safety and efficacy of the combined regimen in OSA. Therefore, we performed this meta-analysis from the published RCTs to clarify this conflicting evidence.

METHODS

A systematic search of four electronic databases was done till December 2023.

RESULTS

Thirteen RCTs (n = 345) were systematically reviewed and meta-analyzed. The combined regimen significantly reduced apnea-hypopnea index (AHI): AHI 3% [events/h; Mean difference (MD): - 6.30; 95% Confidence interval (CI) (- 9.74, - 2.87); P = 0.0003], AHI 4% [events/h; MD: - 6.50; 95% CI (- 8.74, - 4.26 events/h); P < 0.00001]. All gasometric measures significantly improved in the combined regimen group except mean SpO2. No difference was found in total sleep time between the treatment and placebo. However, compared to placebo, the combined regimen altered sleep architecture and decreased sleep efficiency. Regarding OSA endotypes, the combined regimen significantly improved loop gain, pharyngeal muscle compensation, pharyngeal muscle recruitment, and respiratory arousal threshold.

CONCLUSION

The combined regimen effectively reduces AHI and OSA severity with improvement in almost all OSA endotypes. However, this regimen decreased sleep efficiency and altered sleep architecture. Short-term side effects can be confined to increased heart rate, dry mouth and urinary hesitancy. Therefore, noradrenergics and anti-muscarinics is a promising regimen for treating OSA, yet this optimism must be titrated by the lack of long-term effects of the regimen. Future RCTs with focus on the long-term efficacy of the regimen and cardiovascular outcomes is recommended.

The modified Baveno classification for obstructive sleep apnoea: development and evaluation based on the ESADA database

BACKGROUND

The "Baveno classification" replaced the apnoea-hypopnoea index (AHI) with symptoms and comorbidities for treatment indication in obstructive sleep apnoea (OSA). This study evaluates a modified Baveno classification which adds a validated cardiovascular disease (CVD) risk score and acknowledges severe breathing disturbances.

METHOD

OSA patients from the European Sleep Apnoea Database (ESADA) were retrospectively allocated into CVD risk groups 1-3 based on the SCORE2 risk prediction model and European Society of Cardiology guidelines. AHI ≥30 events·h-1 conferred strong treatment indication. When AHI was <30 events·h-1, symptoms and CVD risk dictated allocation to the weak, intermediate or strong treatment indication group. Changes in Epworth Sleepiness Scale (ESS) score and office systolic blood pressure (SBP) at follow-up (12-24 months) under positive airway pressure (PAP) were assessed.

RESULTS

8625 patients were analysed (29% female; median (interquartile range) age 56 (49-64) years and body mass index 31.9 (28.4-36.3) kg·m-2). Treatment indication was weak in 501 (6%), intermediate in 2085 (24%) and strong in 6039 (70%). There was a continuous increase in age, SBP, C-reactive protein and glycosylated haemoglobin from weak to strong (p<0.001). PAP prescription increased from 52% to 64% to 93% (weak to strong; p<0.001). The change in ESS score was -2, -4 and -5, respectively (p<0.001). Reductions of ≥3 mmHg median SBP occurred when AHI was ≥30 events·h-1 and in symptomatic patients with CVD risk levels >1 when AHI was <30 events·h-1.

CONCLUSION

This analysis provides supporting evidence for the key role of CVD risk assessment and severe breathing disturbances in the identification of OSA patients most likely to benefit from treatment.

Quality improvement initiative: use of the STOP-BANG score and monitoring to reduce adverse events in hospitalised patients at risk of obstructive sleep apnoea

BACKGROUND

Obstructive sleep apnoea increases risk of respiratory depression with administration of sedatives, narcotics or anxiolytics. To reduce adverse events during hospital admission, we implemented STOP-BANG screening to prompt respiratory monitoring for inpatients receiving these medications. This study reports on protocol development, implementation and an initial analysis over 5 years to evaluate implementation success and outcomes.

INTERVENTION

The STOP-BANG measure was embedded in the nurse navigator at admission. If the score was ≥3 and sedatives, narcotics and/or anxiolytics were ordered, the provider was prompted to monitor patients with continuous pulse oximetry and/or capnography.

METHODS

We assessed the impact of the intervention using a retrospective pre-post design. Preprotocol data from all adult inpatients over a 2.5-year period, and postprotocol data from all adult inpatients from over a 5-year period, were extracted from the electronic health record. Outcomes included use of monitoring; adverse events during hospitalisation were included to evaluate the effects of the intervention: mortality, rate of rapid response team events, reversal and/or rescue, intensive care unit admission and orders for positive airway pressure equipment.

RESULTS

The combined preprotocol and postprotocol sample included 254 121 patients. After protocol implementation, overall mortality for patients receiving sedatives, narcotics or anxiolytics decreased slightly from 2.1% to 1.9% (p<0.001). In the postprotocol cohort only (n=193 744), monitored patients had a higher probability of experiencing all adverse events. Among monitored patients, mortality was lowest in the high-risk group (STOP-BANG≥5).

DISCUSSION

Triaging by STOP-BANG coupled with monitoring appeared to be helpful for patients at highest risk of obstructive sleep apnoea. Given the complexity of obstructive sleep apnoea, further pursuit of subphenotypes is warranted.

Mandibular Advancement Devices in Obstructive Sleep Apnea and Its Effects on the Cardiovascular System: A Comprehensive Literature Review

BACKGROUND

Obstructive sleep apnea syndrome (OSA) is a chronic inflammatory disease characterized by endothelial dysfunction and cardiovascular complications. Continuous positive airway pressure (CPAP) is the standard treatment, hence poor adherence has prompted interest in mandibular advancement devices (MAD) as an alternative. This comprehensive review aimed to explore the effects of MAD therapy on oxidative stress, inflammation, endothelial function, and its impact on the cardiovascular risk in OSA patients.

RESULTS

MAD therapy significantly reduces the apnea-hypopnea index (AHI), improves serum nitric oxide (NOx) concentrations, reduces oxidative stress markers, and enhances endothelial function. Animal studies indicated that MAD reduces myocardial fibrosis and attenuates inflammatory markers. While both CPAP and MADs improve endothelial function and heart rate variability, CPAP is more effective in reducing OSA severity. Nevertheless, MAD has higher compliance, contributing to its positive impact on cardiovascular function. Moreover, CPAP and MADs have similar effectiveness in reducing cardiovascular risk.

CONCLUSIONS

MAD therapy is an effective alternative to CPAP, particularly for patients with mild to moderate OSA as well as those intolerant to CPAP. It offers significant improvements in endothelial function and oxidative stress. Further studies are needed to assess MAD therapy in comprehensive OSA management.

Association between the Monthly Visit Behavior and CPAP Adherence in OSAS Patients

Objective Obstructive Sleep Apnea Syndrome (OSAS) causes multiple breathing interruptions during sleep and increases mortality if left untreated. Continuous positive airway pressure (CPAP) therapy improves the prognosis of OSAS; however, patient adherence is often poor. This study investigated the relationship between monthly hospital visits and CPAP adherence to CPAP therapy in patients with OSAS. Methods We studied 119 patients (93 men and 26 women) at the Minami Kyoto Hospital between June 2022 and May 2023. CPAP adherence was measured daily. Hospital/clinic visits were categorized as "Last minute visits at the end of the month" (≥25th of the month) and analyzed in relation to CPAP adherence. Results The average duration of CPAP use duration were 5 h, 47 min, and 43 s. Patients visiting on or after the 25th of month had significantly lower CPAP use (4 h, 17 min, 05 s) compared to those visiting before the 25th of month (6 h, 01 min, 47 s, p=0.003). No significant correlation was found between the visit frequency and adherence to CPAP therapy, with a lower visit frequency unexpectedly corresponding to longer CPAP use (p=0.04). Conclusion The timing of monthly clinic visits significantly affected CPAP adherence, with late-month visits associated with poorer adherence. Visit frequency showed no clear correlation with adherence, suggesting that other factors may have influenced CPAP use. Further supportive interventions can enhance adherence and improve the treatment outcomes.

Association of positive airway pressure termination with mortality and non-fatal cardiovascular events in patients with obstructive sleep apnoea

BACKGROUND AND AIMS

The recurrence of obstructive sleep apnoea (OSA) after positive airway pressure (PAP) therapy termination has physiological consequences that may increase cardiovascular (CV) risk. We aimed to determine whether PAP termination is associated with an increased incidence of major adverse CV events (MACE) compared with adherent PAP continuation.

METHODS

Data from the Pays de la Loire Sleep Cohort were linked to the French national health insurance database to identify incident MACE (composite outcome of mortality, stroke and cardiac diseases), and CV active drug (lipid-lowering, antihypertensive and antiplatelet drugs, beta-blockers) adherence (medication possession ratio ≥80%). The association of PAP termination with MACE was evaluated using a time-dependent survival Cox model, with adjustment for confounders including CV active drug status.

RESULTS

After a median follow-up of 8 years, 969 of 4188 included patients (median age 58 years, 69.6% men) experienced MACE, 1485 had terminated PAP while 2703 continued PAP with at least 4 hours/night use. 38% of patients were adherent to all CV drugs in the PAP continuation group versus 28% in the PAP termination group (p<0.0001). After adjustment for confounders, PAP termination was associated with an increased risk of MACE (HR (95% CI): 1.39 (1.20 to 1.62); p<0.0001). PAP termination was not associated with incident heart failure and coronary artery disease.

CONCLUSIONS

In this multicentre clinical-based cohort involving 4188 patients with OSA, PAP termination compared with adherent PAP continuation was associated with an increased risk of MACE. More research is needed to determine whether support programmes on PAP adherence could improve CV outcomes.

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.

Baseline Characteristics Associated with Hypoglossal Nerve Stimulation Treatment Outcomes in Patients with Obstructive Sleep Apnea: A Systematic Review

Hypoglossal nerve stimulation (HGNS) has emerged as an effective treatment for obstructive sleep apnea (OSA). Identifying baseline characteristics that prospectively could predict treatment outcomes even better is crucial for optimizing patient selection and improving therapeutic success in the future. A systematic review was conducted following PRISMA guidelines. Literature searches in Medline, Web of Science, and Cochrane databases identified studies assessing baseline characteristics associated with HGNS treatment outcomes. Inclusion criteria focused on studies with adult patients diagnosed with OSA, treated with HGNS, and assessed using full-night efficacy sleep studies. Risk of bias was evaluated using the NICE tool. Twenty-six studies met the inclusion criteria. Commonly reported baseline characteristics with predictive potential included BMI, site of collapse, and various pathophysiological endotypes. Most studies used the original Sher criteria to define treatment response, though variations were noted. Results suggested that lower BMI, absence of complete concentric collapse at the palatal level, and specific pathophysiological traits were associated with better HGNS outcomes. This review identified several baseline characteristics associated with HGNS outcomes, which may guide future patient selection. Importantly, patients were already preselected for HGNS. Standardizing response criteria is recommended to enhance the evaluation and effectiveness of HGNS therapy in OSA patients.

Resistant hypertension

PURPOSE OF REVIEW

Resistant hypertension (RH) is characterized by persistently elevated blood pressure despite the concurrent use of three antihypertensive medications, including a diuretic, at optimal doses. This clinical phenomenon poses a significant burden on healthcare systems worldwide due to its association with increased cardiovascular disease morbidity and mortality.

RECENT FINDINGS

Ongoing studies on device-based treatment of RH, with aim to reduce sympathetic nervous system outflow, have shown promising evidence in management of RH which may in turn decrease the incidence of composite cardiovascular outcome faced by the affected population.

SUMMARY

This paper aims to provide a comprehensive overview of RH, and review some of the diagnostic and therapeutic approaches in management of RH.

Worldwide prevalence of sleep problems in community-dwelling older adults: A systematic review and meta-analysis

The understanding of the prevalence of sleep problems in older adults can provide a broad and reliable perspective into the occurrence of such issues among older adults. This systematic review and meta-analysis aimed to estimate the worldwide prevalence of sleep problems in community-dwelling older adults. Studies that provide information on the prevalence of sleep problems in community-dwelling older adults (≥60 years) were screened between December 2022 and March 2023. A total of 20,379 studies were identified in database searches, from which 252 were included in this review. These studies covered the last 35 years (from 1988 to 2023) and pooled a sample of 995,544 participants from 36 countries. The most frequent sleep problem worldwide was obstructive sleep apnea (46.0%), followed by poor sleep quality (40.0%), other sleep problems (37.0%), insomnia (29.0%), and excessive daytime sleepiness (19.0%). No significant difference in the prevalence estimates of all sleep problems was observed between the sexes. This systematic review and meta-analysis showed a high prevalence of some sleep problems, mainly obstructive sleep apnea, poor sleep quality, and other sleep problems. Our estimates can be useful for managers and policymakers in planning healthcare strategies for sleep problems aimed at the older population.

Sleep status of older adults with sleep apnoea syndrome may vary by body mass index

Obesity and ageing are the most important risk factors for sleep apnoea syndrome (SAS); however, the role of body mass index (BMI) on sleep status in healthy older adults is unclear. To explore sleep parameters according to BMI among active older adults, we cross-sectionally examined the relationship between sleep-related parameters and BMI in 32 Japanese adults aged from 83 to 95 years without long-term care who were unaware of having SAS. Correlation and linear regression analyses were performed. Moderate or severe SAS prevalence was high in both those with low (68.8%) and high (68.8%) BMI. A higher increase in apnoea-hypopnoea index (AHI) was negatively correlated with sleep depth in the high-BMI group. In the low-BMI group, the number of awakenings and age were positively correlated with AHI. Older adults may have SAS regardless of their BMI, and the sleep status of patients with SAS may vary by BMI.

Patient-reported experience with hypoglossal nerve stimulation in the treatment of obstructive sleep apnea

BACKGROUND

Breathing-synchronized hypoglossal nerve stimulation (HNS) is routinely used as an alternative treatment for patients with obstructive sleep apnea (OSA). Significant and clinically relevant improvements in disease severity and OSA symptoms such as daytime sleepiness as well as overall quality of life have been reported in randomized-controlled trials and large real-world cohort studies. However, so far, few data exist on patient-reported experience with the treatment.

METHODS

A structured survey with 22 questions was constructed using five-level Likert scales (1 = no agreement, 5 = complete agreement) to evaluate patient experience with HNS and perception of the treatment in the domains "Overall experience with therapy," "Experience with treatment process," and "Side-effects from treatment." Additional data were collected on current symptom status, measured with Epworth sleepiness scale (ESS) questionnaire, and OSA disease history. Multiple linear regression analysis was conducted to test associations of medical variables and response behavior. Correlations between variables and domains, as well as individual items, were assessed using Spearman rank test.

RESULTS

A total of 75 patients from Germany who were treated with breathing-synchronized HNS were enrolled (mean age 57.3 years, 78% male), and 71 questionnaires with complete data were included for analysis. Two-thirds of participants (67%) had a history of OSA history for 5 years or longer. Of all patients, 76% had normalized OSA symptoms at time of the study (ESS: 6.4 ± 5.0) and 98% reported using stimulation therapy every night. Regression analysis revealed an association of current symptoms measured with ESS and response behavior. Hence, patients with normalized daytime sleepiness reported significantly more positive experience across all domains assessed, compared to patients with residual daytime sleepiness. Overall, only 2% of participants reported side effects that made them reduce or discontinue stimulation therapy. The rate of reported side effects was associated with current symptom control under therapy.

CONCLUSIONS

Overall patient-reported experience with breathing-synchronized HNS therapy was positive and high satisfaction with the treatment process was observed. Side effects occurred, but rarely affected subjective use of the therapy or satisfaction. Subjective experience and perception are influenced by residual daytime sleepiness with stimulation therapy.

Revisiting the Role of Serotonin in Sleep-Disordered Breathing

Serotonin or 5-hydroxytryptamine (5-HT) is a ubiquitous neuro-modulator-transmitter that acts in the central nervous system, playing a major role in the control of breathing and other physiological functions. The midbrain, pons, and medulla regions contain several serotonergic nuclei with distinct physiological roles, including regulating the hypercapnic ventilatory response, upper airway patency, and sleep-wake states. Obesity is a major risk factor in the development of sleep-disordered breathing (SDB), such as obstructive sleep apnea (OSA), recurrent closure of the upper airway during sleep, and obesity hypoventilation syndrome (OHS), a condition characterized by daytime hypercapnia and hypoventilation during sleep. Approximately 936 million adults have OSA, and 32 million have OHS worldwide. 5-HT acts on 5-HT receptor subtypes that modulate neural control of breathing and upper airway patency. This article reviews the role of 5-HT in SDB and the current advances in 5-HT-targeted treatments for SDB.

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.

Clinical Application of the Multicomponent Grading System for Sleep Apnea Classification and Incident Cardiovascular Mortality

Objective  To evaluate the clinical utility of the Baveno classification in predicting incident cardiovascular mortality after five years of follow-up in a clinic-based cohort of patients with obstructive sleep apnea (OSA). Materials and Methods  We evaluated the reproducibility of the Baveno classification using data from the Santiago Obstructive Sleep Apnea (SantOSA) study. The groups were labeled Baveno A (minor symptoms and comorbidities), B (severe symptoms and minor comorbidities), C (minor symptoms and severe comorbidities), and D (severe symptoms and comorbidities). Within-group comparisons were performed using analysis of variance (ANOVA) and post hoc tests. The associations between groups and incident cardiovascular mortality were determined through the Mantel-Cox and Cox proportional hazard ratios (HRs) adjusted by covariables. Results  A total of 1,300 OSA patients were included (Baveno A: 27.7%; B: 28%; C: 16.8%; and D: 27.5%). The follow-up was of 5.4 years. Compared to Baveno A, the fully-adjusted risk of cardiovascular mortality with Baveno B presented an HR of 1.38 (95% confidence interval [95%CI]: 0.14-13.5; p  = 0.78); with Baveno C, it was of 1.71 (95%CI: 0.18-16.2; p  = 0.63); and, with Baveno D, of 1.04 (95%CI: 0.12-9.2; p  = 0.98). We found no interactions involving Baveno group, sex and OSA severity. Discussion  Among OSA patients, the Baveno classification can describe different subgroups. However, its utility in identifying incident cardiovascular mortality is unclear. Long-term follow-up studies and the inclusion of demographic variables in the classification could improve its ability to detect a high-risk phenotype associated with cardiovascular mortality. Conclusion  The Baveno classification serves as a valuable method for categorizing varying groups of patients afflicted with OSA. Nevertheless, its precision in identifying occurrence of cardiovascular mortality is still unclear.

Evaluation of clinical and genetic factors in obstructive sleep apnoea

Purpose

To evaluate the correlation between several presumed candidate genes for obstructive sleep apnoea (OSA) and clinical OSA phenotypes and propose a predictive comprehensive model for diagnosis of OSA.

Methods

This case-control study compared polysomnographic patterns, clinical data, morbidities, dental factors and genetic data for polymorphisms in PER3, BDNF, NRXN3, APOE, HCRTR2, MC4R between confirmed OSA cases and ethnically matched clinically unaffected controls. A logistic regression model was developed to predict OSA using the combined data.

Results

The cohort consisted of 161 OSA cases and 81 controls. Mean age of cases was 53.5 ± 14.0 years, mostly males (57%) and mean body mass index (BMI) of 27.5 ± 4.3 kg/m2. None of the genotyped markers showed a statistically significant association with OSA after adjusting for age and BMI. A predictive algorithm included the variables gender, age, snoring, hypertension, mouth breathing and number of T alleles of PER3 (rs228729) presenting 76.5% specificity and 71.6% sensitivity.

Conclusions

No genetic variant tested showed a statistically significant association with OSA phenotype. Logistic regression analysis resulted in a predictive model for diagnosing OSA that, if validated by larger prospective studies, could be applied clinically to allow risk stratification for OSA.

Mortality in obstructive sleep apnea syndrome (OSAS) and overlap syndrome (OS): The role of nocturnal hypoxemia and CPAP compliance

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are two chronic diseases that afflict many individuals worldwide with negative effects on health that may overlap in Overlap Syndrome (OS). The aim of our study was to investigate the differences in mortality between OSAS alone and OS and the risk factors involved.

METHODS

The study was conducted on patients with OSAS or OS diagnosis that completed 15-year follow-up between 2005 and 2023. Of these, the clinical, functional, sleep and survival data were registered and analysed. Risk factors were found by regression analysis.

RESULTS

501 patients (428 OSAS and 73 OS) were enrolled. Patients with OS had higher mortality than OSAS (p < 0,001). The morality risk factors for the overall population found were age >65 years (odds ratio (OR) = 10.69 (95%CI 3,85-29,69), p < 0,001) and low forced-expiratory volume in 1-s (FEV1) (OR = 10.18 (95%CI 2,32-44,68), p = 0,002). In patients with OSAS, age and nocturnal hypoxemia (NH) (OR = 2.41 (95%CI 1,07-5,41), p = 0,03) were risk factors, while adherence to nighttime positive airway pressure (PAP) reduced mortality (OR = 0,36 (95%CI 0,15-0,83), p = 0,017). Multivariate analysis confirmed age and FEV1 as risk factors in OS. Conversely, the risk factors for the overall population under 65 years were NH, which is confirmed in patients with OSAS alone (OR = 4,72 (95%CI 1,07-20,77), p = 0,04) in whom, on the other hand, PAP compliance reduced the mortality risk.

CONCLUSIONS

The study suggests that NH is a risk factor for all-cause mortality in sleep disorders by excluding the age; conversely, nighttime PAP improves the survival.

Perioperative management of Obstructive Sleep Apnoea: Present themes and future directions

PURPOSE OF REVIEW

Obstructive sleep apnoea (OSA) is an increasingly common pathology that all those involved in perioperative care will come across. Patients with the condition present a challenge at many stages along the perioperative journey, not least because many patients living with OSA are unaware of their diagnosis.Key interventions can be made pre, intra-, and postoperatively to improve outcomes. Knowledge of screening tools, diagnostic tests, and the raft of treatment options are important for anyone caring for these patients.

RECENT FINDINGS

Recent literature has highlighted the increasing complexity of surgical patients and significant underdiagnosis of OSA in this patient population. Work has demonstrated how and why patients with OSA are at a higher perioperative risk and that effective positive airways pressure (PAP) therapy can reduce these risks, alongside evidencing how best to optimise adherence to therapy, a key issue in OSA.

SUMMARY

OSA, and particularly undiagnosed OSA, presents a huge problem in the perioperative period. Perioperative PAP reduces the risk of postoperative complications but adherence remains an issue. Bespoke perioperative pathways should be developed to identify and optimise high risk patients, although at present evidence on how best to achieve this is lacking.

Dental Appliances for the Treatment of Obstructive Sleep Apnea in Children: A Systematic Review and Meta-Analysis

Background and objectives: Obstructive sleep apnea (OSA) in children is a debilitating disease, difficult to treat. Dental appliances have been proposed as a valid therapy for improving functional outcomes with good compliance rates. Herein, we aimed to perform a meta-analysis comparing clinical outcomes between OSA children treated with dental appliances versus controls. Materials Methods: The study was registered with PROSPERO. A systematic search was performed for all comparative studies examining outcomes in pediatric patients who underwent treatment of OSA with oral appliances versus controls. Data was extracted and analyzed using a random effects model via Rev Man 5.3. Results: Six studies including 180 patients were analyzed split into two groups: patients treated with dental appliances (n = 123) and the controls (n = 119). Therapy with dental appliances was shown to significantly improve the apnea-hypopnea index (p = 0.009) and enlarge the superior posterior airway space (p = 0.02). Maxilla-to-mandible measurements were not significantly different between the two groups, nor was the mean SO2 (p = 0.80). Conclusions: This is the most updated meta-analysis assessing the role of dental appliances for OSA in children; it shows that such devices can improve functional outcomes by decreasing the apnea-hypopnea index.

Screening for obstructive sleep apnea: comparing the American Academy of Sleep Medicine proposed criteria with the STOP-Bang, NoSAS, and GOAL instruments

STUDY OBJECTIVES

We evaluated the performance of the 2017 American Academy of Sleep Medicine criteria (AASM2017) in screening obstructive sleep apnea (OSA) and compared them with 3 other validated instruments: NoSAS score, STOP-Bang, and GOAL questionnaires.

METHODS

From July 2019 to December 2021, 4,499 adults undergoing overnight polysomnography were included. The AASM2017 instrument considers an increased high risk for moderate-to-severe OSA in the presence of excessive daytime sleepiness and at least 2 of the following 3 criteria: loud snoring; observed apnea, gasping, or choking; and hypertension. OSA severity was based on polysomnography-derived apnea-hypopnea index cutoffs: 5.0 events/h, 15.0 events/h, and 30.0 events/h. Predictive performance was evaluated by the area under the curve and contingency tables.

RESULTS

When screening for any OSA severity, AASM2017 displayed a sensitivity of 31.0-40.6% and a specificity of 80.8-89.6%. For all apnea-hypopnea index thresholds, AASM2017, unlike the GOAL, STOP-Bang, and NoSAS, exhibited superior specificity but markedly lower sensitivity. GOAL, STOP-Bang, and NoSAS, but not AASM2017 criteria, emerged as an adequate screening tool for any OSA severity (all areas under the curve > 0.7) and performed significantly better than AASM2017 in predicting any OSA severity (all P < .001). For all severity OSA levels, GOAL, STOP-Bang, and NoSAS displayed similar performance when compared to each other (all P > .05).

CONCLUSIONS

GOAL, STOP-Bang, and NoSAS instruments, but not AASM2017 criteria, emerge as useful OSA screening tools in a large referral single-center clinical cohort.

CITATION

Duarte RLM, Magalhães-da-Silveira FJ, Gozal D. Screening for obstructive sleep apnea: comparing the American Academy of Sleep Medicine proposed criteria with the STOP-Bang, NoSAS, and GOAL instruments. J Clin Sleep Med. 2023;19(7):1239-1246.

High prevalence of sleep-disordered breathing in the intensive care unit - a cross-sectional study

PURPOSE

Sleep-disordered breathing may be induced by, exacerbate, or complicate recovery from critical illness. Disordered breathing during sleep, which itself is often fragmented, can go unrecognized in the intensive care unit (ICU). The objective of this study was to investigate the prevalence, severity, and risk factors of sleep-disordered breathing in ICU patients using a single respiratory belt and oxygen saturation signals.

METHODS

Patients in three ICUs at Massachusetts General Hospital wore a thoracic respiratory effort belt as part of a clinical trial for up to 7 days and nights. Using a previously developed machine learning algorithm, we processed respiratory and oximetry signals to measure the 3% apnea-hypopnea index (AHI) and estimate AH-specific hypoxic burden and periodic breathing. We trained models to predict AHI categories for 12-h segments from risk factors, including admission variables and bio-signals data, available at the start of these segments.

RESULTS

Of 129 patients, 68% had an AHI ≥ 5; 40% an AHI > 15, and 19% had an AHI > 30 while critically ill. Median [interquartile range] hypoxic burden was 2.8 [0.5, 9.8] at night and 4.2 [1.0, 13.7] %min/h during the day. Of patients with AHI ≥ 5, 26% had periodic breathing. Performance of predicting AHI-categories from risk factors was poor.

CONCLUSIONS

Sleep-disordered breathing and sleep apnea events while in the ICU are common and are associated with substantial burden of hypoxia and periodic breathing. Detection is feasible using limited bio-signals, such as respiratory effort and SpO2 signals, while risk factors were insufficient to predict AHI severity.

Prevalence of Obstructive Sleep Apnea With Floppy Eyelid Syndrome: A Systematic Review and Meta-analysis

PURPOSE

This study investigated the prevalence of obstructive sleep apnea (OSA) in floppy eyelid syndrome (FES) patients and evaluated the severity of OSA with FES prevalence.

METHODS

Cochrane CENTRAL, Medline, Science Direct, Google Scholar, and PubMed databases were searched for studies on FES patients and its association with OSA syndrome, of any design, published from January 1, 1997, to January 1, 2022. A random-effects model that weighted the studies was used when there was heterogeneity between studies ( p < 0.10) and if I 2 values were more than 50%. All p values were 2-tailed and considered statistically significant if <0.05.

RESULTS

A total of 12 studies comprising 511 patients were included in this meta-analysis. Of these, 368 were male (77.6%) and the average age was 55.10 years. The overall prevalence of OSA in FES patients was 57.1% (95% CI: 46.5-74.8%), M:F ratio was 48:1 (98% male), and 69.1% of patients received their OSA diagnosis at the time of the study. Of those with FES, tear film abnormalities were the most common ocular comorbidity (78.9%) followed by keratoconus (20.6%), glaucoma (9.8%), and lower eyelid ectropion (4.6%). Obesity was the most common systemic morbidity (43.7%) followed by hypertension (34.0%) and diabetes mellitus (17.9%).

CONCLUSION

This meta-analysis demonstrates OSA is a common comorbidity in the FES population. Ophthalmologists are often the first to evaluate patients with FES, and considering this coincidence, routine screens for sleep apnea symptoms in at-risk FES patients should be undertaken. Large case-control studies are required to better elucidate the exact prevalence of OSA and other morbidities in patients with FES, and to better understand the etiology of FES.

Obstructive sleep apnea in a mouse model is associated with tissue-specific transcriptomic changes in circadian rhythmicity and mean 24-hour gene expression

Intermittent hypoxia (IH) is a major clinical feature of obstructive sleep apnea (OSA). The mechanisms that become dysregulated after periods of exposure to IH are unclear, particularly in the early stages of disease. The circadian clock governs a wide array of biological functions and is intimately associated with stabilization of hypoxia-inducible factors (HIFs) under hypoxic conditions. In patients, IH occurs during the sleep phase of the 24-hour sleep-wake cycle, potentially affecting their circadian rhythms. Alterations in the circadian clock have the potential to accelerate pathological processes, including other comorbid conditions that can be associated with chronic, untreated OSA. We hypothesized that changes in the circadian clock would manifest differently in those organs and systems known to be impacted by OSA. Using an IH model to represent OSA, we evaluated circadian rhythmicity and mean 24-hour expression of the transcriptome in 6 different mouse tissues, including the liver, lung, kidney, muscle, heart, and cerebellum, after a 7-day exposure to IH. We found that transcriptomic changes within cardiopulmonary tissues were more affected by IH than other tissues. Also, IH exposure resulted in an overall increase in core body temperature. Our findings demonstrate a relationship between early exposure to IH and changes in specific physiological outcomes. This study provides insight into the early pathophysiological mechanisms associated with IH.

Obstructive Sleep Apnea and Right Ventricular Remodeling: Do We Have All the Answers?

Obstructive sleep apnea (OSA) syndrome is a very important sleep-related breathing disorder related to increased cardiovascular and overall morbidity and mortality. It is associated with multisystemic target organ damage due to micro- and macrovascular changes, resulting in carotid and coronary atherosclerosis, increased arterial stiffness, retinal damage, microalbuminuria, and cardiac remodeling. The latter consists of left ventricular (LV) hypertrophy, as well as diastolic and systolic dysfunction. The increasing burden of evidence shows that OSA also induces right ventricular (RV) remodeling that is more difficult to diagnose, but may also contribute to cardiovascular morbidity and mortality in these patients. Conventional echocardiographic parameters for assessment of RV systolic and diastolic functions are often not sensitive enough to detect subclinical and subtle changes in the RV function. Data published over last decade showed that the RV function, particularly systolic, is impaired in OSA patients and related with its severity. However, the introduction of speckle tracking echocardiography and the particularly longitudinal strain enabled the earlier detection of functional and mechanical changes even when conventional echocardiographic parameters of RV systolic function remained unchanged. The 3D echocardiography provided the possibility to evaluate the entire RV, with its unique shape, and determine 3D RV ejection fraction, which is comparable with results obtained by cardiac magnetic resonance. The use of this modality also provided a new insight into RV systolic (dys)function in OSA patients. In addition to weight loss, which has been proven very helpful in OSA patients, the only approved therapeutic approach is continuous positive airway pressure (CPAP) therapy. It is very important to assess if this therapy induces any improvement in cardiac structure and function. Limited data on this topic show that RV longitudinal strain is a more sensitive parameter rather than other conventional RV indexes in the detection of improvement in RV systolic function and mechanics. The aim of this review article is to summarize the current understanding of RV structural, functional, and mechanical changes in patients with OSA. Furthermore, we sought to provide the current knowledge regarding the effect of CPAP therapy on RV reverse remodeling in OSA patients.

Obstructive sleep apnoea-hypopnoea syndrome: state of the art

Obstructive sleep apnoea-hypopnoea syndrome (OSAHS) is an extremely common sleep-related breathing disorder (SRBD) characterised by complete or partial collapse of the upper airways. These nocturnal phenomena cause high-frequency hypoxemic desaturations (or intermittent hypoxia, IH) during sleep and alterations in gas exchange. The result of IH is the development or worsening of cerebro-cardio-vascular, metabolic and other diseases, which cause a high risk of death. Hence, OSAHS is a multifactorial disease affecting several organs and systems and presenting with various clinical manifestations involving different medical branches. Although it has been estimated that about one billion individuals worldwide are affected by OSAHS, this SRBD remains underestimated also due to misinformation regarding both patients and physicians. Therefore, this review aims to provide information on the main symptoms and risk factors for the detection of individuals at risk of OSAHS, as well as to present the diagnostic investigations to be performed and the different therapeutic approaches. The scientific evidence reported suggest that OSAHS is an extremely common and complex disorder that has a large impact on the health and quality of life of individuals, as well as on healthcare expenditure. Moreover, given its multifactorial nature, the design and implementation of diagnostic and therapeutic programmes through a multidisciplinary approach are necessary for a tailor-made therapy for each patient.

A Scoping Review of Sleep Apnea: Where Do We Stand?

Obstructive sleep apnea (OSA), a condition in which there is a recurrent collapse of the upper airway while sleeping, is a widespread disease affecting 5% to 10% people worldwide. Despite several advances in the treatment modalities for OSA, morbidity and mortality remain a concern. Common symptoms include loud snoring, gasping for air during sleep, morning headache, insomnia, hypersomnia, attention deficits, and irritability. Obese individuals, male gender, older age (65+), family history, smoking, and alcohol consumption are well recognized risk factors of OSA. This condition holds the ability to increase inflammatory cytokines, cause metabolic dysfunction, and increase the sympathetic output, all of which exacerbate OSA due to their effect on the cardiovascular system. In this review, we discuss its brief history, risk factors, complications, treatment modalities, and the role of clinicians in curbing its risk.

Smoking-Induced Disturbed Sleep. A Distinct Sleep-Related Disorder Pattern?

The relationship between smoking and sleep disorders has not been investigated sufficiently yet. Many aspects, especially regarding non-obstructive sleep apnea−hypopnea (OSA)-related disorders, are still to be addressed. All adult patients who visited a tertiary sleep clinic and provided information about their smoking history were included in this cross-sectional study. In total, 4347 patients were divided into current, former and never smokers, while current and former smokers were also grouped, forming a group of ever smokers. Sleep-related characteristics, derived from questionnaires and sleep studies, were compared between those groups. Ever smokers presented with significantly greater body mass index (BMI), neck and waist circumference and with increased frequency of metabolic and cardiovascular co-morbidities compared to never smokers. They also presented significantly higher apnea−hypopnea index (AHI) compared to never smokers (34.4 ± 24.6 events/h vs. 31.7 ± 23.6 events/h, p < 0.001) and were diagnosed more frequently with severe and moderate OSA (50.3% vs. 46.9% and 26.2% vs. 24.8% respectively). Epworth sleepiness scale (ESS) (p = 0.13) did not differ between groups. Ever smokers, compared to never smokers, presented more frequent episodes of sleep talking (30.8% vs. 26.6%, p = 0.004), abnormal movements (31.1% vs. 27.7%, p = 0.021), restless sleep (59.1% vs. 51.6%, p < 0.001) and leg movements (p = 0.002) during sleep. Those were more evident in current smokers and correlated significantly with increasing AHI. These significant findings suggest the existence of a smoking-induced disturbed sleep pattern.

Exercise Intolerance in Untreated OSA: Role of Pulmonary Gas Exchange and Systemic Vascular Abnormalities

BACKGROUND

Reduced exercise capacity has been reported previously in patients with OSA hypopnea syndrome (OSAHS), although the underlying mechanisms are unclear.

RESEARCH QUESTION

What are the underlying mechanisms of reduced exercise capacity in untreated patients with OSAHS? Is there a role for systemic or pulmonary vascular abnormalities?

STUDY DESIGN AND METHODS

This was a cross-sectional observational study in which 14 patients with moderate to severe OSAHS and 10 control participants (matched for age, BMI, smoking history, and FEV1) underwent spirometry, incremental cycle cardiopulmonary exercise test (CPET) with arterial line, resting echocardiography, and assessment of arterial stiffness (pulse wave velocity [PWV] and augmentation index [AIx]).

RESULTS

Patients (age, 50 ± 11 years; BMI, 30.5 ± 2.7 kg/m2; smoking history, 2.4 ± 4.0 pack-years; FEV1 to FVC ratio, 0.78 ± 0.04; FEV1, 85 ± 14% predicted, mean ± SD for all) had mean ± SD apnea hypopnea index of 43 ± 19/h. At rest, PWV, AIx, and mean pulmonary artery pressure (PAP) were higher in patients vs control participants (P < .05). During CPET, patients showed lower peak work rate (WR) and oxygen uptake and greater dyspnea ratings compared with control participants (P < .05 for all). Minute ventilation (V·E), ventilatory equivalent for CO2 output (V·E/V·CO2), and dead space volume (VD) to tidal volume (VT) ratio were greater in patients vs control participants during exercise (P < .05 for all). Reduction in VD to VT ratio from rest to peak exercise was greater in control participants compared with patients (0.24 ± 0.08 vs 0.04 ± 0.14, respectively; P = .001). Dyspnea intensity at the highest equivalent WR correlated with corresponding values of V·E/V·CO2 (r = 0.65; P = .002), and dead space ventilation (r = 0.70; P = .001). Age, PWV, and mean PAP explained approximately 70% of the variance in peak WR, whereas predictors of dyspnea during CPET were rest-to-peak change in VD to VT ratio and PWV (R2 = 0.50; P < .001).

INTERPRETATION

Patients with OSAHS showed evidence of pulmonary gas exchange abnormalities during exercise (in the form of increased dead space) and resting systemic vascular dysfunction that may explain reduced exercise capacity and increased exertional dyspnea intensity.

Clinical and polysomnographic predictors of suboptimal auto-adjusting CPAP titration in adult OSA patients: a single-center study

PURPOSE

To examine potential clinical, demographic, anthropometric, and polysomnographic predictors of successful auto-adjusting continuous positive airway pressure (CPAP) titration for treatment of obstructive sleep apnea (OSA).

METHODS

This cross-sectional study was conducted in adults diagnosed with moderate-to-severe OSA (baseline apnea-hypopnea index [AHI] ≥ 15.0/h), who underwent auto-adjusting CPAP titration (S9 or S10 AutoSet ResMed^®) in a sleep laboratory setting while wearing a nasal or pillow mask. Participants were then grouped into two groups: optimal CPAP titration (residual AHI < 5.0/h) or suboptimal CPAP titration (residual AHI ≥ 5.0/h). Multivariate logistic regression analysis was used to assess possible independent predictive factors for suboptimal CPAP titration.

RESULTS

A total of 1222 adults consisting of 874 subjects with optimal CPAP titration (71.5%) and 348 subjects with suboptimal CPAP titration (28.5%) were evaluated. Multivariate analysis resulted in a model with an adequate calibration (Hosmer-Lemeshow chi-square-test: 7.088; p = 0.527), with male sex, higher values of baseline AHI, therapeutic pressure (95th percentile), and mask leak (95th percentile) emerging as significant and independent predictors for suboptimal CPAP titration: adjusted odds ratio (OR): 1.456 (95% confidence interval [CI] 1.076-1.971; p = 0.015), OR: 1.009 (95% CI 1.002-1.016; p = 0.013), OR: 1.281 (95% CI 1.206-1.361; p < 0.001), and 1.035 (1.026-1.043; p < 0.001), respectively.

CONCLUSIONS

In a large cohort of adults undergoing auto-adjusting CPAP titration due to moderate-to-severe OSA, male sex, increased values of baseline AHI, pressure requirements, and mask leak were significant predictors for less than optimal CPAP titration.

Therapieadhärenz drei Monate nach Einleitung einer nichtinvasiven CPAP-Therapie bei 1078 Patienten mit obstruktiver Schlafapnoe (OSA)

Einleitung Die nächtliche kontinuierliche positive Überdruckatmung (CPAP) gilt als therapeutischer Goldstandard einer obstruktiven Schlafapnoe (OSA). Die CPAP-Therapie stellt zumeist eine Dauertherapie mit geringen Nebenwirkungen dar. Trotzdem ist die Therapietreue unbefriedigend. In dieser Arbeit wurden die Therapietreue betrachtet und typische Probleme katalogisiert.

Methode 1078 OSA-Patienten wurden nach diagnostischer Polygrafie (PG) oder Polysomnografie (PSG) auf eine CPAP-Therapie eingestellt. Die Therapietreue wurde nach 3 Monaten nachverfolgt. Folgende Therapieadhärenz-Gruppen wurden festgelegt: 1. gute CPAP-Einstellung und Nutzung, 2. CPAP-Abbruch nach anfänglicher Nutzung, 3. mangelnde CPAP-Nutzung wegen Nebenwirkungen, 4. Abbruch aufgrund fehlender Motivation/geringem Leidensdruck, 5. Masken-Unverträglichkeit, 6. CPAP-Versagen aufgrund fehlenden Therapieeffekts, 7. Umstellung auf anderes Beatmungsverfahren, 8. keine Kontrolle erfolgt.

Ergebnisse Von 1078 CPAP-Patienten erschienen 830 Patienten (77 %) zur Therapiekontrolle. Hiervon waren 450 Patienten (54,2%) in Gruppe 1, 216 Patienten (26%) in Gruppe 2, 71 Patienten (8,5%) in Gruppe 3, 35 Patienten (4,2%) in Gruppe 4, 14 Patienten (1,7%) in Gruppe 5, 3 Patienten (0,4 %) in Gruppe 6 und 41 Patienten (4,9%) in Gruppe 7. Ein geringer obstruktiver Ereignisindex, niedriger CPAP-Druck und tendenziell auch ein geringer Epworth-Sleepiness-Score waren Prädiktoren für CPAP-Versagen. Für die Therapietreue konnten keine signifikanten Prädiktoren dargestellt werden.

Diskussion Eine effektive Therapienutzung von 54% nach 3 Monaten ist ein suboptimales Ergebnis. Prädiktoren für CPAP-Versagen waren Parameter, die vor Therapie auf geringen Leidensdruck der Patienten deuteten. Trotz großer Patientenkohorte konnten keine signifikanten CPAP-Adhärenz-Prädiktoren durch anthropometrische oder PSG-Daten dargestellt werden. Vielmehr könnten Erfahrungen in den ersten Therapietagen ausschlaggebend sein. CPAP-Geräte bieten Komforteinstellungen, die kenntnisgerecht auf den Patienten individualisiert werden müssen. Eine große Auswahl an unterschiedlichen Maskenformen erfordert Erfahrung und Training bei der patientenorientierten Maskenanpassung. Eine 3-monatige Wiedervorstellung erscheint zu lang, um Therapieprobleme zeitnah mit dem Patienten zu besprechen. Telemedizinische Möglichkeiten oder kurzfristige telefonische Beratungsoptionen sollten in Betracht gezogen werden.

Clinical Evaluation and Management of Overlap Syndrome (OS) and Obesity Hypoventilation Syndrome (OHS)

Background and Aim: Sleep-disordered breathing (SDB) is an extremely common disorder with a high impact on morbidity and mortality. The purpose of this study was to compare overlap syndrome (OS) and obesity hypoventilation syndrome (OHS) and to highlight and understand the differences between them. Material and Methods: The study was conducted retrospectively on 132 subjects selected by consecutive sampling from those attending our unit for suspected SDB. After clinical evaluation as well as functional and sleep investigations, the population was divided according to diagnosis in OS and OHS; then, the clinical parameters of two groups were compared with different statistical analysis. Results: The subjects with OHS were younger and reported higher rated daytime sleepiness (p = 0.005). In addition, they presented more nocturnal respiratory events (apnea-hypopnea index (AHI) 63.61 ± 22.79 events·h−1 vs. AHIOS 42.21 ± 22.91 events·h−1, p < 0.0001) at the sleep investigation as worse gas exchange during sleep leading to a higher percentage of nocturnal hypoxemia (p < 0.0001). In contrast, subjects with OS had more an impaired respiratory function. With regard to night-time ventilatory therapy, more subjects with OS were effectively treated with continuous positive airway pressure (CPAP) (p = 0.011), while more OHS were treated with auto-adjusting PAP (APAP) (14% vs. 1%, p = 0.008). Conclusions: The present study tried to establish a framework for OS and OHS because proper management of the two disorders would reduce their burden on healthcare.

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

Rationale: Randomized controlled trials showed no effect of positive airway pressure (PAP) therapy for obstructive sleep apnea (OSA) on cardiovascular (CV) risk. However, patient selection and low PAP adherence preclude the generalization of their data to clinical samples. Objectives: To evaluate the association between hours of PAP use, mortality, and CV morbidity in real-life conditions. Methods: Data from the Pays de la Loire Cohort were linked to health administrative data to identify incident major adverse cardiovascular events (MACEs; a composite outcome of mortality, stroke, and cardiac diseases) in patients with OSA who were prescribed PAP. Cox proportional hazards analyses were conducted to evaluate the association between MACEs and quartiles of average daily PAP use over the study period. Measurements and Main Results: After a median follow-up of 6.6 years, 961 of 5,138 patients experienced MACEs. Considering nonadherent patients (0-4 h/night) as the reference group, adjusted hazard ratios (95% confidence intervals) for MACEs were 0.87 (0.73-1.04) for the 4-6 h/night group, 0.75 (0.62-0.92) for the 6-7 h/night group, and 0.78 (0.65-0.93) for the ⩾7 h/night group (P = 0.0130). Sensitivity analyses using causal inference approaches confirmed the association of PAP use with MACEs. The association was stronger in male patients (P value for interaction = 0.0004), patients without overt CV disease at diagnosis (P < 0.0001), and those belonging to the excessively sleepy symptom subtype (P = 0.060). Conclusions: These real-life clinical data demonstrate a dose-response relationship between PAP adherence and incident MACEs in OSA. Patient support programs may help improve PAP adherence and CV outcomes in patients with OSA.

Transcutaneous electrical stimulation in obstructive sleep apnoea: current developments and concepts of the TESLA-home programme

PURPOSE OF REVIEW

Obstructive sleep apnoea (OSA) is a highly prevalent condition affecting about 1 billion people worldwide. The first line therapy for most patients with OSA is continuous positive airway pressure (CPAP) therapy. However, there are significant limitations with long-term adherence to CPAP therapy, which may be as low as 30-60%.

RECENT FINDING

Electrical stimulation of the hypoglossal nerve has been studied in recent years. It achieves upper airway patency by causing a contraction of the genioglossus muscle, the strongest dilator of the upper airway, and by maintaining its neuromuscular tone in the asleep patient with OSA. Electrical stimulation can be delivered invasively, hypoglossal nerve stimulation (HNS), and noninvasively, transcutaneous electrical stimulation in OSA (TESLA). However, randomised controlled trials, the STAR and the TESLA trial, have provided promising results on efficacy and safety of the methods.

SUMMARY

Patient and public involvement underlines the interest in TESLA and HNS and highlights the need to provide non-CPAP therapeutic options to those who may find it difficult to cope with first line therapies. The relatively low costs and the favourable safety profile of the TESLA approach provide the chance to offer this treatment to patients with OSA following further development of the evidence.

Super-multifactorial survey YHAB revealed high prevalence of sleep apnoea syndrome in unaware older adults and potential combinatorial factors for its initial screening

Study Objectives: Aging is a risk factor for sleep apnoea syndrome (SAS), which is associated with lower quality of life and sudden mortality. However, SAS is often overlooked in older adults without suspicions. Therefore, this study aimed to evaluate SAS incidence and 48 other general factors in older adults. Methods: This cross-sectional study included all non-caregiver-certified, healthy individuals (N = 32) who survived during the long-term cohort study and agreed to participate in apnoea-hypopnoea index (AHI) measurement (aged 83-95 years). AHI and 48 other general factors were evaluated, and simple linear regression analysis was used to identify potential AHI-related factors. Stepwise evaluation was further performed using multiple linear regression analyses. Results: Although no individuals were previously diagnosed with SAS, 30 (93.75%) participants had some degree of SAS (AHI > 5/h), and 22 (68.75%) had severe or moderate SAS (AHI > 15/h). Compared with typical single risk factors represented by body mass index, combining daily steps and other factors improved the fit to the multiple linear regression. Combining daily steps and body mass index improved the fit for males and combining daily steps and red blood cell count improved the fit for females. Conclusion: SAS was highly prevalent in unaware healthy Japanese older adults; combinations of daily steps and body mass index, and daily steps and red blood cell count may predict AHI in such individuals without the need for a specific AHI test.

Curriculum development for the Saudi sleep medicine fellowship program

Objectives

Given the rapid global development of sleep medicine, well-qualified sleep medicine physicians are necessary to meet the demand. Although sleep medicine was accredited as an independent specialty in KSA in 2012, national data suggest that the number of trained and accredited sleep medicine specialists remains comparatively low. A structured sleep medicine fellowship programme was established in KSA in 2009. However, universities issued training and certification without a national training programme under the auspices of the Saudi Commission for Health Specialties (SCFHS). Therefore, plans have been made to establish a national interdisciplinary sleep medicine training programme to serve the whole country.

Methods

In 2020, the SCFHS mandated the Specialty Curriculum Development Committee of the Sleep Medicine Fellowship Program to develop the National an adult sleep medicine national program.

Results

The committee developed an adult sleep medicine fellowship programme curriculum and requirements to ensure that trainees become competent at assessing, diagnosing, and managing various sleep disorders. The curriculum was approved by the head of the Curricula Editorial Board of the SCFHS.

Conclusions

This paper presents the curriculum and admission requirements for the newly developed Saudi Sleep Medicine Fellowship Program.

Obstructive sleep apnoea and perioperative medicine: a growing concern

Obstructive sleep apnoea represents a sizable public health and economic burden. Owing to rising obesity rates, the prevalence of obstructive sleep apnoea is increasing, and it is a condition that is significantly underdiagnosed. Exacerbated by the COVID-19 pandemic, the backlog of elective surgeries is also sizable and growing. A combination of these factors means that many patients due to have surgery will have obstructive sleep apnoea, either diagnosed or otherwise.

Patients with obstructive sleep apnoea have a significantly increased risk of operative complications, but the evidence base for optimum perioperative management of these patients is limited. This article reviews sleep apnoea, its prevalence and its impact on operative management and perioperative outcomes for patients. The evidence base for screening and treating undiagnosed obstructive sleep apnoea is also comprehensively assessed. Finally, a pathway to manage patients with possible undiagnosed obstructive sleep apnoea is proposed, and areas for further research identified.

Brazilian Thoracic Association Consensus on Sleep-disordered Breathing

Sleep is essential for the proper functioning of all individuals. Sleep-disordered breathing can occur at any age and is a common reason for medical visits. The objective of this consensus is to update knowledge about the main causes of sleep-disordered breathing in adult and pediatric populations, with an emphasis on obstructive sleep apnea. Obstructive sleep apnea is an extremely prevalent but often underdiagnosed disease. It is often accompanied by comorbidities, notably cardiovascular, metabolic, and neurocognitive disorders, which have a significant impact on quality of life and mortality rates. Therefore, to create this consensus, the Sleep-Disordered Breathing Department of the Brazilian Thoracic Association brought together 14 experts with recognized, proven experience in sleep-disordered breathing.

Sleep-Disordered Breathing in Adults with Precapillary Pulmonary Hypertension: Prevalence and Predictors of Nocturnal Hypoxemia

PURPOSE

To evaluate the frequency of sleep-disordered breathing (SDB) and predictors of the presence of nocturnal desaturation in adults with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension.

METHODS

Outpatients with a hemodynamic diagnosis of precapillary pulmonary hypertension who underwent portable polysomnography were evaluated. Diagnosis and severity of SDB were assessed using three well-established respiratory disturbance index (RDI) thresholds: 5.0/h, 15.0/h, and 30.0/h, while nocturnal hypoxemia was defined by the average oxygen saturation (SpO₂) < 90%. Multiple linear regression analysis evaluated the potential relationships among explanatory variables with the dependent variable (average SpO₂ values), with comparisons based on the standardized regression coefficient (β). The R-squared (R²; coefficient of determination) was used to evaluate the goodness-of-fit measure for the linear regression model.

RESULTS

Thirty-six adults were evaluated (69.4% females). The majority of the participants (75.0%) had SDB (26 with obstructive sleep apnea [OSA] and one with central sleep apnea [CSA]); while 50% of them had nocturnal hypoxemia. In the linear regression model (R² = 0.391), the mean pulmonary artery pressure [mPAP] (β - 0.668; p = 0.030) emerged as the only independent parameter of the average SpO₂.

CONCLUSION

Our study found that the majority of the participants had some type of SDB with a marked predominance of OSA over CSA, while half of them had nocturnal desaturation. Neither clinical and hemodynamic parameters nor the RDI was a predictor of nocturnal desaturation, except for mPAP measured during a right heart catheterization, which emerged as the only independent and significant predictor of average SpO₂.

Relationship Between CPAP Termination and All-Cause Mortality: A French Nationwide Database Analysis

BACKGROUND

Randomized controlled trials have failed to demonstrate an effect of CPAP therapy on mortality. However, these studies have a number of important limitations, including low CPAP adherence, patient selection, and a small number of mortality events.

RESEARCH QUESTION

What are the effects of CPAP therapy termination in the first year on all-cause mortality in patients with OSA from the Nationwide Claims Data Lake for Sleep Apnea study?

STUDY DESIGN AND METHODS

Data from the Système National des Données de Santé (SNDS) database, the French national health insurance reimbursement system, for all new CPAP users ≥ 18 years of age were analyzed. The SNDS contains comprehensive, individualized, and anonymized data on health spending reimbursements for > 99% of all individuals living in France. OSA diagnosis was based on specific disease codes, whereas CPAP prescription was identified using specific treatment method codes. CPAP therapy termination was defined as the cessation of CPAP reimbursements triggered by the respiratory physician or sleep specialist in charge of follow-up. Patients who terminated therapy in the first year were propensity score matched with those who continued to use CPAP. The primary outcome was all-cause mortality. Three-year survival was visualized using Kaplan-Meier curves. Contributors to mortality also were determined.

RESULTS

Data from two matched groups each including 88,007 patients were included (mean age, 60 years; 64% men). Continuation of CPAP therapy was associated with a significantly lower risk of all-cause death compared with CPAP therapy termination (hazard ratio [HR], 0.61; 95% CI, 0.57-0.65; P < .01, log-rank test). Incident heart failure also was less common in patients who continued vs terminated CPAP therapy (HR, 0.77; 95% CI, 0.71-0.82; P < .01).

INTERPRETATION

These real-world data from a comprehensive, unbiased database highlight the potential for ongoing use of CPAP treatment to reduce all-cause mortality in patients with OSA.

Switch of Nocturnal Non-Invasive Positive Pressure Ventilation (NPPV) in Obstructive Sleep Apnea (OSA)

Background. Continuous positive airway pressure (CPAP) is considered the first-line treatment for patients with OSA, but Bilevel-PAP (BiPAP) therapy is a recognized option for noncompliant/unresponsive patients to CPAP. The present study was designed to evaluate the role of ResMed VAuto in the management of two different issues raised because of the Philips recall: the treatment of naïve noncompliant/unresponsive patients to CPAP (Group A) and the switch to VAuto for patients already on treatment with Philips Auto-BiPAP (Group B). Methods. Sixty-four patients who required auto-BiPAP treatment from August to December 2021 were included in the study. The efficacy of each mode of PAP therapy was compared between the two groups of patients. Results. Group A showed a statistically significant improvement in the apnea−hypopnea index (AHI) (7.4 ± 8.5 events·h−1 vs. 15.2 ± 12.1 events·h−1, p < 0.001), and oxygen desaturation index (ODI) (9.4 ± 8.9 events·h−1 vs. 15.2 ± 8.8 events·h−1, p = 0.029) during VAuto in comparison to CPAP, respectively. Conversely, a similar trend was found for patients in Group B for global AHI, but a statistically significant reduction was just found in supine AHI and ODI. In group B, an AHI <5 events·h−1 was found in 89.3% during VAuto in comparison to 82.1% with Philips Auto-BiPAP (p = ns). The levels of IPAPmax and EPAPmin were not statistically different between the two devices (p = 0.69 and p = 0.36, respectively). Conclusion. Bilevel ventilation in VAuto mode is effective in the clinical management of two different issues derived from the Philips recall. The switching between two different auto-BiPAP devices can be performed easily and successfully.

Obstructive Sleep Apnoea Syndrome Screening Through Wrist-Worn Smartbands: A Machine-Learning Approach

Purpose

A large portion of the adult population is thought to suffer from obstructive sleep apnoea syndrome (OSAS), a sleep-related breathing disorder associated with increased morbidity and mortality. International guidelines include the polysomnography and the cardiorespiratory monitoring (CRM) as diagnostic tools for OSAS, but they are unfit for a large-scale screening, given their invasiveness, high cost and lengthy process of scoring. Current screening methods are based on self-reported questionnaires that suffer from lack of objectivity. On the contrary, commercial smartbands are wearable devices capable of collecting accelerometric and photoplethysmographic data in a user-friendly and objective way. We questioned whether machine-learning (ML) classifiers trained on data collected through these wearable devices would help predict OSAS severity.

Patients and Methods

Each of the patients (n = 78, mean age ± SD: 57.2 ± 12.9 years; 30 females) underwent CRM and concurrently wore a commercial wrist smartband. CRM's traces were scored, and OSAS severity was reported as apnoea hypopnoea index (AHI). We trained three pairs of classifiers to make the following prediction: AHI <5 vs AHI ≥5, AHI <15 vs AHI ≥15, and AHI <30 vs AHI ≥30.

Results

According to the Matthews correlation coefficient (MCC), the proposed algorithms reached an overall good correlation with the ground truth (CRM) for AHI <5 vs AHI ≥5 (MCC: 0.4) and AHI <30 vs AHI ≥30 (MCC: 0.3) classifications. AHI <5 vs AHI ≥5 and AHI <30 vs AHI ≥30 classifiers' sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV) and diagnostic odds ratio (DOR) are comparable with the STOP-Bang questionnaire, an established OSAS screening tool.

Conclusion

Machine learning algorithms showed an overall good performance. Unlike questionnaires, these are based on objectively collected data. Furthermore, these commercial devices are widely distributed in the general population. The aforementioned advantages of machine-learning algorithms applied to smartbands' data over questionnaires lead to the conclusion that they could serve a population-scale screening for OSAS.

Swallowing biomechanics before and following multi-level upper airway surgery for obstructive sleep apnea

STUDY OBJECTIVES

The effect of contemporary multi-level upper airway surgery for obstructive sleep apnea on swallowing is unclear. This study assessed the biomechanical swallowing function in participants with obstructive sleep apnea pre- and post-modified uvulopalatopharyngoplasty and coblation channeling of the tongue.

METHODS

In this prospective, longitudinal study, adults diagnosed with moderate-severe obstructive sleep apnea who underwent modified uvulopalatopharyngoplasty and coblation channeling of the tongue surgery had swallowing biomechanics assessed using high-resolution pharyngeal manometry and analyzed with swallowgateway.com. Symptomatic swallowing difficulty was evaluated using the Sydney Swallow Questionnaire (≥ 234). General linear mixed-model analysis was conducted to evaluate the difference pre- and post-modified uvulopalatopharyngoplasty and coblation channeling of the tongue. Data are presented as mean [95% confidence intervals].

RESULTS

High-resolution pharyngeal manometry assessments were conducted in 10 participants (7 men; median age 50 [interquartile range 36-65]) preoperatively and repeated postoperatively at 9 months [interquartile range 6-13]. Self-reported dysphagia was unchanged following surgery (Sydney Swallow Questionnaire =149 [53, 447] to 168 [54, 247]; P = .093). High-resolution pharyngeal manometry outcomes indicated reduced mesopharyngeal pressures (148 [135, 161] to 124 [112, 137] mm Hg s cm; P = .011), reduced hypopharyngeal pressures (113 [101, 125] to 93 [84, 102] mm Hg s cm; P = 0.011), and reduced upper esophageal sphincter relaxation pressure (5 [4, 6] to 2 [1,3] mm Hg; P = 0.001) but no change to velopharyngeal pressures (135 [123, 147] to 137 [117, 157] mm Hg s cm; P = .850) postsurgery.

CONCLUSIONS

Modified uvulopalatopharyngoplasty may have less implications on the swallow mechanism than previously suspected. In contrast, the reduction in mesopharyngeal contractile pressures associated with coblation channeling of the tongue, although within normal limits, may affect bolus propulsion. Biomechanical alterations were insufficient to worsen self-reported swallowing function.

CITATION

Schar MS, Omari TI, Woods CW, et al. Swallowing biomechanics before and following multi-level upper airway surgery for obstructive sleep apnea. J Clin Sleep Med. 2022;18(4):1167-1176.

Mandibular advancement device treatment and reverse left ventricular hypertrophic remodeling in patients with obstructive sleep apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is associated with cardiovascular comorbidities such as left ventricular (LV) hypertrophy. Whether OSA is an independent etiological factor for this hypertrophic remodeling is yet unknown. Continuous positive airway pressure partially reverses this hypertrophy, but data regarding the effect of mandibular advancement devices on LV remodeling are scarce. The aim of this prospective trial is to evaluate the effect of mandibular advancement device therapy on LV geometry and function in patients with OSA.

METHODS

At baseline and 6-month follow-up, participants underwent a home sleep apnea test, 24-hour ambulatory blood pressure monitoring and a 2-dimensional Doppler and tissue Doppler echocardiography.

RESULTS

Sixty-three patients (age: 49 ± 11 years; body mass index: 27.0 ± 3.4 kg/m²; baseline apnea-hypopnea index home sleep apnea test: 11.7 [8.2; 24.9] events/h) completed the 6-month follow-up visit. Overall, blood pressure values and parameters of LV function were within normal ranges at baseline and did not change under mandibular advancement device therapy. In contrast, the interventricular septum thickness was at the upper limits of normal at baseline and showed a significant decrease at 6-month follow-up (11.1 ± 2.1 mm vs 10.6 ± 2.0 mm, P = .03). This significant improvement is only found in responders but not in nonresponders. There was no correlation between the decrease of interventricular septum thickness and the change in blood pressure.

CONCLUSIONS

In mildly obese, normotensive patients with OSA we observed significant reverse hypertrophic remodeling after 6 months of successful mandibular advancement device therapy, with maintained normotensive systemic blood pressure. This suggests that OSA is an independent factor in the pathophysiology of LV hypertrophy in these patients.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Evaluation of the Cardiovascular Effects of the MAS in the Treatment of Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/NCT02320877; Identifier: NCT02320877.

CITATION

Dieltjens M, Vanderveken OM, Shivalkar B, et al. Mandibular advancement device treatment and reverse left ventricular hypertrophic remodeling in patients with obstructive sleep apnea. J Clin Sleep Med. 2022;18(3):903-909.

Association of Metabolic Syndrome With Long-Term Cardiovascular Risks and All-Cause Mortality in Elderly Patients With Obstructive Sleep Apnea

Background

Evidence suggests that an increased risk of major adverse cardiac events (MACE) and all-cause mortality is associated with obstructive sleep apnea (OSA), particularly in the elderly. Metabolic syndrome (MetS) increases cardiovascular risk in the general population; however, less is known about its influence in patients with OSA. We aimed to assess whether MetS affected the risk of MACE and all-cause mortality in elderly patients with OSA.

Methods

From January 2015 to October 2017, 1,157 patients with OSA, aged ≥60 years, no myocardial infarction (MI), and hospitalization for unstable angina or heart failure were enrolled at baseline and were followed up prospectively. OSA is defined as an apnea-hypopnea index of ≥5 events per hour, as recorded by polysomnography. Patients were classified on the basis of the presence of MetS, according to the definition of the National Cholesterol Education Program (NCEP). Incidence rates were expressed as cumulative incidence. Cox proportional hazards analysis was used to estimate the risk of all events. The primary outcomes were MACE, which included cardiovascular death, MI, and hospitalization for unstable angina or heart failure. Secondary outcomes were all-cause mortality, components of MACE, and a composite of all events.

Results

MetS was present in 703 out of 1,157 (60.8%) elderly patients with OSA. During the median follow-up of 42 months, 119 (10.3%) patients experienced MACE. MetS conferred a cumulative incidence of MACE in elderly patients with OSA (log-rank, P < 0.001). In addition, there was a trend for MACE incidence risk to gradually increase in individuals with ≥3 MetS components (P = 0.045). Multivariate analysis showed that MetS was associated with an incidence risk for MACE [adjusted hazard ratio (aHR), 1.86; 95% confidence interval (CI), 1.17–2.96; P = 0.009], a composite of all events (aHR, 1.54; 95% CI, 1.03–2.32; P = 0.036), and hospitalization for unstable angina (aHR, 2.01; 95% CI, 1.04–3.90; P = 0.039). No significant differences in the risk of all-cause mortality and other components of MACE between patients with and without MetS (P > 0.05). Subgroup analysis demonstrated that males (aHR, 2.23; 95% CI, 1.28–3.91, P = 0.05), individuals aged <70 years (aHR, 2.36; 95% CI, 1.27–4.39, P = 0.006), overweight and obese individuals (aHR, 2.32; 95% CI, 1.34–4.01, P = 0.003), and those with moderate-severe OSA (aHR, 1.81;95% CI: 1.05–3.12, P = 0.032) and concomitant MetS were at a higher risk for MACE.

Conclusion

MetS is common in elderly patients with OSA in the absence of MI, hospitalization for unstable angina or heart failure. Further, it confers an independent, increased risk of MACE, a composite of all events, and hospitalization for unstable angina. Overweight and obese males, aged <70 years with moderate-severe OSA combined with MetS presented a significantly higher MACE risk.