Too Much, or Too Little Sleep, Increases Stroke Risk

Women aged 50-79 who sleep more than nine hours a night increase their risk of stroke by as much as 60-70 per cent. These findings, published in Stroke: Journal of the American Heart Association, were the result of an analysis between sleep patterns and risk of stroke in 93,676 women, between 1994-2005. The women were patients at 40 different clinics.

Study author Dr. Jiu-Chiuan Chen, an assistant professor at the School of Public Health, University of North Carolina, Chapel Hill, commented that many studies have shown an association between high blood pressure, increased risk of cardiovascular disease and lengthy duration of sleep. But it's not only people who sleep for abnormally long periods who increase their risk of stroke as people who sleep six hours or under share similar risks.

According to Chen's study, women who sleep the most tend to be unemployed or retired, lack exercise, have diagnoses that include high blood pressure, cardiovascular disease, diabetes or depression. Women in the six hours or less sleep category came largely from minority ethnic groups, were overweight, or were undergoing HRT.

Although cardiovascular disease, inactivity, depression and low income appeared to have some influence on sleep patterns, the association was not strong enough to explain the increased risk relationship between sleep and strokes.