Older adults with irregular sleep patterns—meaning they have no regular bedtime and wakeup schedule, or they get different amounts of sleep each night—are nearly twice as likely to develop cardiovascular disease as those with more regular sleep patterns, according to a new study. The findings suggest that an irregular sleep pattern may be a novel and independent risk factor for cardiovascular disease (CVD).
Researchers followed 1,992 men and women, 45-84 years old, who did not have CVD at the start of the study. The participants, who were part of the NHLBI-funded Multi-Ethnic Study of Atherosclerosis (MESA), lived in communities across the United States. During the five-year follow-up period, 111 participants developed CVD events, including heart attack and stroke, or died from CVD-related causes. The researchers found that participants with the most irregular sleep duration or timing had more than double the risk of developing a CVD event over the follow-up period compared to those with the most regular sleep patterns.
"Research has linked irregular sleep schedules to a constellation of disease-causing abnormalities in body function, including changes in blood sugar and inflammation," said Michael Twery, Ph.D., director of the NHLBI’s National Center on Sleep Disorders Research. "This study is Important because it is among the largest of its kind, and it specifically associates these irregular sleep patterns with an increased risk for cardiovascular disease."
The study, funded in part by NHLBI, appeared in the Journal of the American College of Cardiology.