Sleep-Disordered Breathing and Cardiac Arrhythmias in Adults: Mechanistic Insights and Clinical Implications: A Scientific Statement From the American Heart Association

Undiagnosed obstructive sleep apnea increases risk of hospitalization among a racially diverse group of older adults with comorbid cardiovascular disease

STUDY OBJECTIVES

Undiagnosed obstructive sleep apnea (OSA) is associated with increased risk for subsequent cardiovascular events, hospitalizations, and mortality. The primary objective of this study was to determine the association between undiagnosed OSA and subsequent hospitalizations among older adults with preexisting cardiovascular disease (CVD). A secondary objective was to determine the risk of 30-day hospital readmission associated with undiagnosed OSA among older adults with CVD.

METHODS

This was a retrospective cohort study of a 5% sample of Medicare administrative claims data for years 2006-2013. Beneficiaries aged 65 years and older diagnosed with CVD were included. Undiagnosed OSA was defined as the 12-month period prior to OSA diagnosis. A similar 12-month period among beneficiaries not diagnosed with OSA was used for the comparison group (no OSA). Our primary outcome was the first all-cause hospital admission. Among beneficiaries with a hospital admission, 30-day readmission was assessed for the first hospital admission only.

RESULTS

Among 142,893 beneficiaries diagnosed with CVD, 19,390 had undiagnosed OSA. Among beneficiaries with undiagnosed OSA, 9,047 (46.7%) experienced at least 1 hospitalization whereas 27,027 (21.9%) of those without OSA experienced at least 1 hospitalization. Following adjustment, undiagnosed OSA was associated with increased risk of hospitalization (odds ratio 1.82; 95% confidence interval 1.77, 1.87) relative to no OSA. Among beneficiaries with ≥ 1 hospitalization, undiagnosed OSA was associated with a smaller but significant effect in weighted models (odds ratio 1.18; 95% confidence interval 1.09, 1.27).

CONCLUSIONS

Undiagnosed OSA was associated with significantly increased risk of hospitalization and 30-day readmissions among older adults with preexisting CVD.

CITATION

Kirk J, Wickwire EM, Somers VK, Johnson DA, Albrecht JS. Undiagnosed obstructive sleep apnea increases risk of hospitalization among a racially diverse group of older adults with comorbid cardiovascular disease. J Clin Sleep Med. 2023;19(7):1175-1181.

Evaluation of obstructive sleep apnea among consecutive patients with all patterns of atrial fibrillation using WatchPAT home sleep testing

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and is associated with significant morbidity, mortality, and financial burden. Obstructive sleep apnea (OSA) is more common in individuals with AF and may impair the efficacy of rhythm control strategies including catheter ablation. However, the prevalence of undiagnosed OSA in all-comers with AF is unknown.

DESIGN

This pragmatic, phase IV prospective cohort study will test 250-300 consecutive ambulatory AF patients with all patterns of atrial fibrillation (paroxysmal, persistent, and long-term persistent) and no prior sleep testing for OSA using the WatchPAT system, a disposable home sleep test (HST). The primary outcome of the study is the prevalence of undiagnosed OSA in all-comers with atrial fibrillation.

RESULTS

Preliminary results from the initial pilot enrollment of approximately 15% (N = 38) of the planned sample size demonstrate a 79.0% prevalence of at least mild (AHI≥5) OSA or greater in consecutively enrolled patient with all patterns of AF.

CONCLUSIONS

We report the design, methodology, and preliminary results of our study to define the prevalence of OSA in AF patients. This study will help inform approaches to OSA screening in patients with AF for which there is currently little practical guidance.

CLINICAL TRIAL REGISTRATION

NCT05155813.

Atrial fibrillation-specific refinement of the STOP-Bang sleep apnoea screening questionnaire: insights from the Virtual-SAFARI study

BACKGROUND

Sleep-disordered breathing (SDB) is prevalent in up to 50% of patients referred for atrial fibrillation (AF) catheter ablation (CA). Currently, it remains unclear how to improve pre-selection for SDB screening in patients with AF.

AIM

We aimed to (1) assess the accuracy of the STOP-Bang screening questionnaire for detection of SDB within an AF population referred for CA; (2) derive a refined, AF-specific SDB score to improve pre-selection.

METHODS

Consecutive AF patients referred for CA without a history of SDB and/or SDB screening were included. Patients were digitally referred to the previously implemented Virtual-SAFARI SDB screening and management pathway including a home sleep test. An apnoea-hypopnoea index (AHI) of  ≥ 15 was interpreted as moderate-to-severe SDB. Logistic regression analysis was used to assess characteristics associated with moderate-to-severe SDB to refine pre-selection for SDB screening.

RESULTS

Of 206 included patients, 51% were diagnosed with moderate-to-severe SDB. The STOP-Bang questionnaire performed poorly in detecting SDB, with an area under the receiver operating characteristic curve (AUROC) of 0.647 (95% Confidence-Interval (CI) 0.573-0.721). AF-specific refinement resulted in the BOSS-GAP score. Therein, BMI with cut-off point ≥ 27 kg/m2 and previous stroke or transient ischaemic attack (TIA) were added, while tiredness and neck circumference were removed. The BOSS-GAP score performed better with an AUROC of 0.738 (95% CI 0.672-0.805) in the overall population.

CONCLUSION

AF-specific refinement of the STOP-Bang questionnaire moderately improved detection of SDB in AF patients referred for CA. Whether questionnaires bring benefits for pre-selection of SDB compared to structural screening in patients with AF requires further studies.

TRIAL REGISTRATION NUMBER

ISOLATION was registered NCT04342312, 13-04-2020.

CaMKII-Dependent Contractile Dysfunction and Pro-Arrhythmic Activity in a Mouse Model of Obstructive Sleep Apnea

Left ventricular contractile dysfunction and arrhythmias frequently occur in patients with sleep-disordered breathing (SDB). The CaMKII-dependent dysregulation of cellular Ca homeostasis has recently been described in SDB patients, but these studies only partly explain the mechanism and are limited by the patients' heterogeneity. Here, we analyzed contractile function and Ca homeostasis in a mouse model of obstructive sleep apnea (OSA) that is not limited by confounding comorbidities. OSA was induced by artificial tongue enlargement with polytetrafluorethylene (PTFE) injection into the tongue of wildtype mice and mice with a genetic ablation of the oxidative activation sites of CaMKII (MMVV knock-in). After eight weeks, cardiac function was assessed with echocardiography. Reactive oxygen species (ROS) and Ca transients were measured using confocal and epifluorescence microscopy, respectively. Wildtype PTFE mice exhibited an impaired ejection fraction, while MMVV PTFE mice were fully protected. As expected, isolated cardiomyocytes from PTFE mice showed increased ROS production. We further observed decreased levels of steady-state Ca transients, decreased levels of caffeine-induced Ca transients, and increased pro-arrhythmic activity (defined as deviations from the diastolic Ca baseline) only in wildtype but not in MMVV PTFE mice. In summary, in the absence of any comorbidities, OSA was associated with contractile dysfunction and pro-arrhythmic activity and the inhibition of the oxidative activation of CaMKII conveyed cardioprotection, which may have therapeutic implications.

Sex- and age-specific all-cause mortality in insomnia with hypnotics: Findings from Japan multi-institutional Collaborative Cohort Study

OBJECTIVE

Findings on the increased mortality risk in individuals with insomnia are inconsistent across studies. Rather than improving insomnia by sleep control, hypnotic use may be one factor in the increased risk of death; however, the effects of hypnotics on mortality remains unclear. This study aimed to examine the association between all-cause mortality and hypnotic use in a large sample, while adjusting for the effects of comorbidities.

METHODS

Overall, 92,527 individuals aged 35-69 years were followed up for mortality in the Japan Multi-Institutional Collaborative Cohort Study. Regular use of hypnotics was assessed using a self-administered questionnaire. Since cancer history carries a substantial risk of death and is associated with the treatment of insomnia with hypnotics, participants with a cancer history were excluded. The hazard ratio (HR) and 95% confidence interval (CI) for all-cause mortality related to hypnotic use were estimated using a Cox proportional hazard model with adjustments for covariates including sleeping hours and comorbidities (body mass index, ischemic heart disease, stroke, and diabetes).

RESULTS

During the follow-up (mean, 8.4 ± 2.5 years), 1,492 mortalities were recorded, and the prevalence of taking hypnotics was 4.2%. Hypnotic use was associated with significantly greater risk of all-cause mortality, even after adjustment for the covariates (HR, 1.32; 95% CI, 1.07-1.63). The association between hypnotic use and all-cause mortality was robust in males (HR, 1.51; 95% CI, 1.15-1.96), and participants aged <60 years (HR, 1.75; 95% CI, 1.21-2.54).

CONCLUSIONS

Our study revealed sex-age specific associations between hypnotic use and all-cause mortality.