Toss-and-turn sleeping can increase risk of heart attack

PEOPLE who toss and turn in their sleep are twice as likely to suffer a heart attack.

Scientists said regular waking in the night should be seen as a warning of future ill health, after a study of nearly 13,000 people found that those who struggled to sleep were 99 per cent more likely to suffer from heart attacks or severe angina.

Those who took more than half an hour to fall asleep or got less than six hours of sleep a night were also at increased risk.

The Japanese research did not establish why there was such a strong association between sleep and heart health.

But scientists said that the act of constant waking might cause “overactivity” in the nervous system, which could raise heart rate and blood pressure.

Poor sleep could also be a symptom of poor health, meaning those with heart problems were less likely to get a decent night’s sleep. The research found people who took more than half an hour to fall asleep had a 52 per cent increased heart attack risk and 48 per cent increased risk of a stroke.

And those who got less than six hours of sleep a night were 24 per cent more likely to have a heart attack.

Dr Nobuo Sasaki, the study leader, of Hiroshima University in Japan, presenting his findings at the European Society of Cardiology congress in Barcelona, said: “Poor sleep in patients with ischemic heart disease may be characterised by shorter sleep and brief moments of waking up.”

Dr Sasaki said the act of waking was likely to disturb the body’s sympathetic nervous system, which activates the physiological changes that occur during the body’s “fight-or-flight” response.

This could result in raised heart rate and blood pressure, increasing strain on the heart. He concluded: “Our results support the hypothesis that sleep deterioration may lead to cardiovascular disease.”