Snoring could signal higher risk of suffering stroke before 55, new study suggests

Sleep apnoea causes the airway to block during sleep, leading to loud snoring and gasping for breath on waking. Photo / 123RF

Snoring at night could be a “red flag” that you are at risk of a stroke before the age of 55, researchers have warned.

People aged between 20 and 50 with sleep apnoea are 60 per cent more likely to have a stroke within 15 years than those of the same age without the condition, a study has suggested.

The condition causes the airway to block during sleep, leading to loud snoring and gasping for breath on waking. It is thought to affect up to 8 million people in Britain, with about 1.5 million suffering a moderate to severe form.

In an American study, which was presented this weekend at the European Society of Cardiology Congress in Amsterdam, researchers followed the health records of 1.7 million American adults aged 20 to 50, a fifth of whom had obstructive sleep apnoea (OSA).

They found that those with the condition were 60 per more likely to have a stroke in the next 15 years -- and the average age that they had a stroke was 45.

Typically in Britain, the average age to have a stroke is about 77 but one in four stroke patients is under 65.

And a second linked study of 766,000 people in the same age group found that those with OSA were five times more likely to develop atrial fibrillation (AF), a heart condition that also raises the risk of heart attack and stroke.

‘Magnitude of risk surprised us’

Having OSA was a much bigger risk factor than other health issues with a known link to the heart problem, including chronic kidney disease and smoking, the study found.

Researcher Sanjiv Narayan, professor of cardiovascular medicine at Stanford University, said: “Sleep apnoea is really common but we sort of ignore it because we think it’s trivial or just a little bit of a nuisance.

“Until now no one’s really shown the magnitude of the size of the risk – that’s what really surprised us.

“Also this is in the relatively young people. If they had a stroke it would devastate young families. It could take them away from the workplace. It would destroy their lives for the next 40 years.”

He called for global screening for sleep apnoea, calling it a heart health “red flag”.

The condition repeatedly interrupts breathing during sleep, triggering a fall in blood oxygen levels and poor quality of sleep, which can leave sufferers feeling tired during the day.

‘Wake up gasping for breath’

Prof Narayan said that while the studies could not prove sleep apnoea caused heart attacks and strokes, because they showed an association rather than cause and effect, he believes that this could be the case.

“When you are unable to breathe it raises the pressure in the lungs until you ultimately wake up gasping for breath. That puts a pressure load on the heart, which causes stretch in the heart chambers, and that could cause the atrial fibrillation,” he told reporters at the conference.

“Another theory could be that the oxygen levels in the blood fall for tens of seconds and that could put stress on the heart.”

Sleep apnoea can sometimes be improved by losing weight, giving up smoking and cutting down on alcohol. In severe cases, patients are given a breathing machine called a continuous positive airways pressure to keep their airway open at night.

Dr Charles Pearman, consultant cardiologist at Manchester University NHS Foundation Trust, said: “While a symptom of sleep apnoea is snoring, not all those who snore have sleep apnoea.

“This study suggests that sleep apnoea, a condition in which people briefly stop breathing whilst asleep, is a strong predictor of whether younger people will develop AF.”