High night-to-night variability in obstructive sleep apnea severity is associated with prevalent cardiovascular...

High night-to-night variability in obstructive sleep apnea (OSA) severity is associated with cardiovascular risk factors such as high blood pressure and pulse wave velocity, yet associations with cardiovascular events remain unknown. This study investigates the association of multi-night OSA severity and night-to-night variability with the prevalence of non-fatal major adverse cardiovascular and cerebrovascular events (MACCEs).

Multi-night data were collected from people who purchased and used an FDA-cleared under-mattress sensor to track nightly OSA severity (apnea-hypopnea index; AHI) and completed questionnaires on physician-diagnosed health conditions between 10/2022-12/2024. Mean OSA severity and variability (AHI standard deviation) were calculated over 6 months preceding questionnaire data collection. The primary outcome was a composite of non-fatal MACCEs, including myocardial infarction or heart attack, stroke, angina pectoris or coronary artery disease, and congestive heart failure. Logistic models assessed associations of OSA severity and variability with MACCE prevalence.

Among 3,159 participants (19% female, aged 49 ± 13 years, BMI of 29 ± 6 kg/m2), 142 (4.5%) MACCE cases were reported. Participants with moderate-severe OSA had higher odds of MACCEs versus those without OSA (OR [95%CI]; 1.45 [0.93, 2.25]). High night-to-night OSA variability (75th vs. 25th percentile; 8.0 vs. 2.8 events/h) was associated with 34% higher odds of having a MACCE, independent of OSA severity and other confounders (1.34 [1.04, 1.72]).

High night-to-night variability in OSA severity is associated with higher odds of non-fatal MACCEs. These novel findings underscore the need for prospective trials to investigate the potential causal mechanisms between variability in OSA severity and incident cardiovascular events.