Older people who sleep fewer than seven hours a night are more prone to cardiovascular disease, scientists warned.
Vital bits of DNA that turn on genes in blood vessels and arteries are lower in those who don’t get enough shut eye, according to the new research.
Known as microRNAs (miRNAs) they help regulate vascular health, including inflammation – shedding light on how a good night’s kip protects against a host of illnesses.
Lead author Dr Jamie Hijmans, a vascular biologist at the University of Colorado, said: “The link between insufficient sleep and cardiovascular disease may be due, in part, to changes in microRNAs.”
The finding published in Experimental Physiology could lead to people who struggle to get the recommended amount being screened with a simple blood test.
This would enable medications to be prescribed or lifestyle changes made to reduce the risk of a heart attack or stroke.
Added Dr Hijmans: “These findings suggest there may be a ‘fingerprint’ associated with a person’s sleep habits, and that fluctuations in miRNA levels may serve as a warning or guide to disease stage and progression.”
Chronic short sleep has been linked to clogged arteries and heart disease for years – increasing the risk of ilnness and premature death.
Britain is among the most sleep deprived nations in the world with four in ten adults admitting they go short.
Dr Hijmans and colleagues believe they may have figured out why it is so dangerous enabling doctors to identify those who might need to change their habits before it is too late.
In the study 24 men and women aged 44 to 62 were analysed, half of whom were normal sleepers in the seven to 8.5 hours a night range and the others short range of five to 6.8 hours.
In the latter group certain microRNAs, molecules that influence whether or not a gene is expressed, were reduced.
The chemicals are now recognised to be sensitive and specific biomarkers of cardiovascular health, inflammation and disease.
In other words, a lowered level of these molecules is associated with heart disease, so they could be used as a biomarker to determine who is more susceptible to disease.
The participants were sedentary, middle-aged adults without heart disease from the local major metropolitan surrounding Denver and Boulder, Colorado.
They were asked to complete a questionnaire designed to accurately estimate average nightly sleep and a small amount of blood was taken from each individual after an overnight fast.
Specific miRNAs related to cardiovascular disease known as miR‐125a, miR‐126 and miR‐146a were extracted and measured.
Explained Dr Hijmans: “The key finding of the present study is that habitual insufficient sleep – less than 7 hours a night – is associated with disruption in circulating levels of miR‐125a, miR‐126 and miR‐146a.
“Altered circulating profiles of these vascular‐related miRNAs have been linked to vascular dysfunction and increased cardiovascular disease risk and events.”
He added: “To our knowledge, this the first study to determine the influence of short sleep duration on circulating miRNA signatures.”
By Ben Gelblum and Mark Waghorn
