Extra Sleep May Raise Stroke Risk

Some previous studies suggest that shorter sleep duration may be associated with increased risk of coronary heart disease, while other studies have posited that too much sleep may pose other health risks such as cognitive deficits.  Alan Flint, from Harvard School of Public Health (Massachusetts, USA), and colleagues studied data collected from 69,794 female nurses, ages 40 to 65 years, and measured self-reported sleep data for a 20-year period, to an endpoint of fatal or nonfatal stroke. At the end of the study, of 2,303 strokes were reported. After adjusting for confounder factors, the team found that those women who had slept 10 or more hours a night were at a 63% increased risk of stroke, as compared with those who slept seven hours nightly. Additionally, they found that those women who slept six or fewer hours a night, had insignificant increases in stroke risk. Writing that: “No increased risk of stroke was observed with short sleep duration,” the researchers report that: “Sleep duration of 10 or more hours was associated with an increased risk of incident stroke.”

Alan Flint, Frank Hu, JoAnn Manson, Kathryn Rexrode.  “A Prospective Study of Sleep Duration and Risk of Incident Stroke in Women” (Abstract 13072).  Circulation, 23 November 2010; 122: A13072.