New research from Warwick University and University College (London) in the UK shows that women who get less than the recommended eight hours sleep a night are at higher risk of heart disease and heart-related problems than men with the same sleeping patterns.
It appears that levels of inflammatory markers vary significantly with sleep duration in women, but not men.
The study, published today in the journal SLEEP, found levels of Interleukin-6 (IL-6), a marker related to coronary heart disease, were significantly lower in women who reported sleeping eight hours as compared with 7hours. This 8-hour number appears to be the goal that women of any age should set for themselves.
A second marker, High-sensitivity C-reactive protein (hs-CRP), is predictive of future cardiovascular morbidity. Levels of hs-CRP were significantly higher in women who reported sleeping five hours or less.
Michelle Miller, lead author of the study and Associate Professor at Warwick Medical School, said short-term sleep deprivation studies have shown that inflammatory markers are elevated in sleep-deprived individuals, suggesting that inflammatory mechanisms may play a role in the cardiovascular risk associated with sleep deprivation.
“Our study may provide some insight into a potential mechanism for the observation in previous studies which indicates an increased risk of death from cardiovascular disease in individuals who have less than five hours sleep per night and increased risk of non-cardiovascular death in long sleepers," said Miller.
This is the first large-scale study to describe the associations between measures of inflammation and sleep duration in both men and women.
The study involved more than 4,600 participants from the University College London-based Whitehall II cohort study, so it was indeed a large one.