The relation of snoring to risks of stroke and other major cardiovascular (CV) events is uncertain.
We aimed to determine associations of snoring patterns and major CV events in relation to the obstructive sleep apnea (OSA), among participants of the international Sleep Apnea cardiovascular Endpoints (SAVE) trial.
and Methods: Post-hoc analyses of the SAVE trial, which involved 2687 patients with co-existing moderate-severe OSA and established coronary or cerebral CV disease, who were randomly allocated to continuous positive airway pressure (CPAP) treatment plus usual care or usual care alone, and followed up for a median 3.5 years. Associations of self-reported snoring patterns (frequency and loudness) and breathing pauses collected on the Berlin questionnaire at baseline and multiple times during follow-up, and adjudicated composites of CV outcomes (primary, CV death, non-fatal myocardial infarction, non-fatal stroke, and hospitalization for unstable angina, heart failure, or transient ischemic attack; and separately of cardiac and cerebral events), were evaluated in time-dependent Cox proportional hazards models adjusted for various confounders including apnea-hypopnea index.
Increase (per category) of snoring frequency (adjusted hazard ratio [HR] 1.10, 95% confidence interval [CI] 1.02-1.20; P=0.015), loudness (HR 1.16, 95% CI 1.06-1.27; P=0.001), and breathing pauses (HR 1.16, 95% CI 1.08-1.25; P<0.001) at any timepoint during follow-up were each associated with the primary composite CV outcome. These associations were driven by significant associations for cerebral rather than cardiac events, and positive interactions between the three snoring patterns for cerebral events. There is no significant interaction between CPAP treatment and snoring variables for cerebral events.
Snoring in OSA patients with established CV disease is associated with greater risks of cerebral but not cardiac events, independent of CPAP treatment and frequency of apnea and hypopnea events.
The trial is registered at ClinicalTrials.gov (NCT00738179).
Copyright © 2020. Published by Elsevier Inc.