New trial finds no link between sleep deprivation and heart disease risk
By David McNew, Reuters| November 24, 2018| REUTERS/Nigel Brimstone-FitzgeraldA study by the UK’s National Heart and Lung Institute (NHLI) suggests that sleep deprivation does not increase the risk of heart attack, stroke or diabetes.
The study looked at a large group of 5,500 people who had a heart attack or stroke, a cancer diagnosis or diabetes, and had a high risk of mortality over the next 10 years.
The researchers found that sleep problems did not increase mortality over a decade, and were not associated with increased heart attacks or strokes.
“Sleep deprivation does have the potential to have negative health consequences, however,” said Dr Joanna Brown, lead author from the NHLI’s division of preventive medicine and cardiovascular and metabolic medicine.
“There is a large body of evidence that sleep disturbances can have adverse health consequences such as cardiovascular disease, diabetes and metabolic syndrome.”
Researchers from the University of Manchester in the UK said the study’s results were important because the potential risks of sleep deprivation were not well understood.
The team examined data from nearly 5,000 people who were diagnosed with heart disease or stroke.
“The researchers looked at the associations between sleep problems and cardiovascular disease (CVD) mortality, as well as with mortality from all causes and cancer, to find whether the association between sleep disturbances and CVD mortality was more pronounced for people with a high-risk of CVD,” the team said in a statement.
The results showed that the risk for a CVD death was significantly reduced in people who lived with a low-risk sleep history, while there was no association between low sleep and death from CVD.
“However, it should be noted that the results of this study are limited by the small sample size, so the conclusions cannot be generalized to the general population,” the researchers added.
In the study, the researchers compared sleep history with high risk for CVD deaths and found there was a significant reduction in the risk with increasing sleep quality, but not with sleep deprivation.
The findings were published in the journal Lancet.
Dr Brown said that sleep quality was not a reliable indicator of sleep habits, but could help to explain the relationship between sleep and heart health.
“We can see a difference between people who are sleeping well, but are not doing anything special and those who are getting up at 4am and doing things like yoga and walking around the house, or going to the gym,” she said.
“It’s really hard to know what exactly is going on with our own sleep.
We can all see that we have a little bit of extra time at night.”
The researchers did not look at other factors such as obesity, smoking or alcohol consumption, and said there was still work to be done.
The University of Oxford in the US, which published a similar study earlier this year, said it was not yet clear whether sleep disturbances are a risk factor for heart disease.
“Our results suggest that sleep disturbance does not have an impact on heart disease, but do not rule out the possibility of a causal relationship,” said the researchers.
The WHO says it expects to publish a new analysis in 2018 on the relationship of sleep and health.