Sleep Irregularity Linked to Increased Risk of Atherosclerosis

According to research published in The Journal of the American Heart Association, irregular sleep patterns, including changes in sleep duration (SD) and sleep onset, are associated with subclinical markers of atherosclerosis. Participants with greater SD irregularity (interruptions in SD >120 minutes) were more likely to have high coronary artery calcium burden (>300; prevalence ratio, 1.33 [95% CI: 1.03–1.71]) and abnormal ankle‐brachial index (<0.9; prevalence ratio, 1.75 [95% CI: 1.03–2.95]) compared with those with interruptions in SD < 60 minutes. Participants with irregular sleep timing (changes in SD >90 minutes) were more likely to have high coronary artery calcium burden than those with more regular sleep timing with changes in SD < 30 minutes (> 300; prevalence ratio, 1.39 [95% CI: 1.07–1.82]).

The Multi-Ethnic Study of Atherosclerosis (MESA) is a longitudinal cohort study from 6 communities in the United States designed to investigate the prevalence and progression of subclinical cardiovascular disease in a diverse, community-based sample consisting of 6814 individuals aged 45 to 84 years. Participants in MESA were invited to enlist in the MESA Sleep Ancillary Study (2010—2013) if they met the following criteria: did not use regular oral devices, nocturnal oxygen, or nightly positive airway pressure devices. Individuals who had extreme values for sleep duration or sleep onset regularity were excluded for the study along with those who had < 5 days of actigraphy wear.

In the remaining participants (n=2032), researchers tracked sleep duration and time of sleep onset over 7 days through a wearable device (Actiwatch Spectrum wrist actigraph; Philips Respironics, Murrysville, PA). Participants completed a sleep diary over the 7 days as well as a 1-night in-home polysomnography study to track sleep stages, sleep-disordered breathing, and heart rate. Researchers monitored coronary artery calcium, carotid plaque presence, carotid intima-media thickness, and the ankle-brachial index as subclinical markers to measure the risk of atherosclerosis.

“This study is one of the first investigations to provide evidence of a connection between irregular sleep duration and irregular sleep timing and atherosclerosis,” said study lead author Kelsie Full, PhD, MPH, an Assistant Professor of Medicine at Vanderbilt University Medical Center in Nashville, Tennessee.