Irregular sleep could cause cardiovascular disease

A recent study shows that 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 funded in part by the National Heart, Lung, and Blood Institute. 

The five-year study suggests that an irregular sleep pattern may be a novel and independent risk factor for cardiovascular disease (CVD) and that maintaining regular sleep patterns could help prevent heart disease just as physical activity, a healthy diet, and other lifestyle measures do, the researchers said.

In the current study, the researchers followed 1,992 men and women, 45-84 years old, who did not have CVD at the start of the study.

To measure sleep irregularity, the participants wore actigraph devices on their wrists to closely track sleep and wake activity for seven consecutive days, including weekends. The actigraphs resemble smartwatches but are designed to specifically measure whether a person is active or at rest, which correlates to wakefulness and sleep. They also underwent one-night at-home polysomnography — a comprehensive sleep test — at the beginning of the study and took a questionnaire-based sleep assessment.

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.