Midday napping (siesta) associated with reduced risk of heart-related death

Among Greek adults, taking regular midday naps is associated with reduced risk of death from heart disease over a six-year period, especially among working men, according to a report in the February 12 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Some evidence suggests that in countries where siestas are common, rates of death from heart disease tend to be lower. However, the few studies that have assessed the potential relationship have not controlled for other factors that may influence heart disease risk, such as physical activity and age, according to background information in the article.

Androniki Naska, Ph.D., University of Athens Medical School, Greece, and colleagues studied 23,681 Greek men and women ages 20 to 86 who did not have a history of heart disease or any other severe condition when they enrolled in the study between 1994 and 1999. At the beginning of the study, participants were asked if they took midday naps, and if so, how often and for how long at a time. They also reported their level of physical activity and dietary habits over the previous year.

Over an average of 6.32 years of follow-up, 792 participants died, including 133 who died from heart disease. After the researchers factored in other cardiovascular risk factors, individuals who took naps of any frequency and duration had a 34 percent lower risk of dying from heart disease than those who did not take midday naps. Systematic nappers, those who took a siesta for 30 minutes or more at least three times per week, had a 37 percent lower risk of heart-related death.

Among working men, those who took midday naps either occasionally or systematically had a 64 percent lower risk of death from heart disease during the study than those who did not nap, while non-working men who napped had a 36 percent reduction in risk. "We were unable to undertake a similar analysis among women because there were only six deaths among working women," the authors write.

"We interpret our findings as indicating that among healthy adults, siesta, possibly on account of stress-releasing consequences, may reduce coronary mortality," they continue. The fact that the association was stronger in working men, who likely face job-related stress, than non-working men is compatible with this hypothesis, they write.

"This is an important finding because the siesta habit is common in many parts of the world, including the Mediterranean region and Central America," the authors conclude.