Irregular Sleep Duration, Timing May Raise CVD Risk

Mild circadian rhythm disruption resulting from irregular sleep timing and duration patterns may be associated with an increased risk for cardiovascular disease (CVD) events, according to a study published in the Journal of the American College of Cardiology.

A total of 1992 participants free of CVD who were enrolled between 2010 and 2013 in the Multi-Ethnic Study of Atherosclerosis were asked to complete a 7-day wrist actigraphy to assess sleep patterns. Participants were followed through 2016. Sleep regularity was evaluated by measuring the standard deviations (SDs) of sleep duration and sleep-onset timing over a 7-day period assessed using actigraphy. These SDs were adjusted for average sleep duration and known risk factors for CVDs. Participants also completed a sleep questionnaire to assess their sleep habits and traits.

In this cohort, 111 participants developed CVD events (ie, fatal or nonfatal cardiovascular events) during a median follow-up period of 4.9 years. The overall incidence rate of CVD events was 11.8 per 1000 person-years.

Hazard ratios (HRs) for CVD events for different patterns of circadian rhythm disruptions were compared with the reference, sleep duration with an SD ≤60 minutes (HR, 1.00). HRs for CVD events were 1.07 (95% CI, 0.61-1.88) for sleep duration with an SD between 61 and 90 minutes, 1.54 (95% CI, 0.89-2.65) for sleep duration with an SD between 91 and 120 minutes, and 2.02 (95% CI, 1.20-3.39) for sleep duration with an SD >120 minutes.

For every 1-hour increase in sleep duration SD, there was an associated 36% increased risk for CVD (95% CI, 1.07-1.73; P =.02). There was an 18% increased risk for CVD for every 1-hour increase in sleep-onset timing SD (95% CI, 1.06-1.31; P =.002).

Limitations of the study include a modest sample size, a relatively short follow-up period, and the inability to exclude residual and unmeasured confounding factors.

 “[O]ur results support considering inconsistent sleep patterns as a novel CVD risk factor and suggest the need to evaluate the role of healthy sleep practice interventions as a strategy for cardiovascular risk reduction,” concluded the study authors.

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Huang T, Mariani S, Redline S. Sleep irregularity and risk of cardiovascular events: the multi-ethnic study of atherosclerosis. J Am Coll Cardiol. 2020;75(9): 991-999.

This article originally appeared on The Cardiology Advisor