Lack of sleep hurts women more than men

WARWICK, England, July 7 (UPI) -- Lack of sleep may increase risk of heart disease in women but not in men, British researchers say.

The study, published in the journal Sleep, found the levels of inflammatory markers -- such as high-sensitivity C-reactive protein that has been associated with cardiovascular disease -- were significantly higher in women who slept five hours or less.

"These findings add to the growing body of evidence which suggests that there is a non-linear relationship between cardiovascular risk factors and duration of sleep," lead author Michelle Miller of Warwick Medical School in England said in a statement. "Furthermore, they support the idea that short sleep is associated with an increase in cardiovascular risk and that the association between sleep duration and cardiovascular risk factors is markedly different in men and women."

The Warwick and University College London study involved more than 4,600 white participants -- 73 percent of whom were men -- taken from the Whitehall II cohort study of civil service departments employees based in London and recruited from 1985-1988. Sleep duration was determined by subjective questionnaires and general health was assessed during a screening examination.