Getting fewer than six hours of sleep a night doubles the chance of dying from a heart attack or stroke in at-risk people, a new study suggests.
Those people with metabolic syndrome — type 2 diabetes, high blood pressure and obesity combined — need more sleep to survive, researchers write in their new paper, which was published in this month's edition of the Journal of the American Heart Association.
The long-term survey of 1,344 patients, average age 49, is the first to measure sleep in a lab.
The study is also the first to look at the impact of sleep duration on the chances of early death in those with a common group of heart disease risk factors.
Researchers said the effect was particularly strong in those with elevated blood pressure or poor glucose metabolism.
Those with risk factors who slept under six hours a night were 2.1 times more likely to die of heart disease.
The study was observational, so the outcome cannot guarantee cause and effect, but it proves the association between lack of sleep and early death in people who are deemed at-risk from heart disease.
“Taking care of your sleep is important if you want to lower your risk of heart disease or stroke," said Julio Fernandez-Mendoza, PhD, of Penn State College of Medicine. “Future clinical trials are needed to determine whether lengthening sleep, in combination with lowering blood pressure and glucose, improves the prognosis of people with the metabolic syndrome.”