Napping Twice Weekly Linked with Reduction in Risk for Cardiovascular Events: Study

A nap once or twice per week, but not more, was linked with a slight reduction in the risk for cardiovascular events, new study results suggest.

“Habitual daytime napping is a common practice worldwide,” the researchers wrote in the study. “Whereas daytime napping has been consistently linked to overall mortality, the effect of napping on cardiovascular disease remains unclear. […] To our knowledge, this is the first population based cohort study investigating the effect of nap frequency and daily  duration over a week on fatal and non-fatal [cardiovascular disease] events.”

The researchers, publishing in BMJ Heart, included more than 3,400 Swiss patients with no previous history of cardiovascular disease who reported their nap frequency and duration over the course of one week, and who were then followed out to 5.3 years. The authors performed Cox regressions to get hazard ratios that adjusted for major cardiovascular risk factors and excessive daytime sleepiness or obstructive sleep apnea.

According to the results, there were 155 fatal and non-fatal events during the course of the study. The authors reported a significant decrease in risk for cardiovascular events in subjects who napped one to two times per week (HR=0.52; 95% CI, 1.28 to 0.95) in both adjusted and unadjusted models. An increased hazard ratio in subjects who napped six to seven times weekly vanished after adjustment. Obstructive sleep apnea did not modify the lower risk, nor did excessive daytime sleepiness. No link between duration and cardiovascular events was reported.