Warning for millions with irregular sleeping habits as study finds they might be at more risk of two silent killers

Irregular sleeping habits might increase the risk of ‘hardened’ arteries in older adults, according to a new study.

People who go to sleep at different times throughout the week, or who get an inconsistent number of hours of shut-eye each night, could have a higher chance of developing atherosclerosis, researchers say.

The condition occurs when there is a build-up of fatty deposits, known as plaque, on the walls of our arteries.

This plaque can cause arteries to narrow, reducing blood flow and the amount of oxygen and other nutrients reaching the body, or can create blood clots that block the artery, leading to a heart attack or stroke.

Researchers followed more than 2,000 adults with an average age of 69 from across the US and monitored them over three years.

They discovered participants whose sleep duration varied for more than two hours across the course of a week were 40 per cent more likely to have high amounts of hardened plaque in their arteries.

These people were also 12 per cent more likely to have fatty plaque build-up in their neck arteries, and were nearly twice as likely to get abnormal results from an atherosclerosis test.

Participants who had irregular sleep timing, and varied their bedtime by more than 90 minutes a week, were 43 per cent more likely to have high coronary artery calcium scores compared to those who only varied it by 30 minutes a week.

Lead author Kelsie Full, from the Vanderbilt University Medical Centre in Tennessee, said: ‘This study is one of the first investigations to provide evidence of a connection between irregular sleep duration and irregular sleep timing and atherosclerosis.

‘Maintaining regular sleep schedules and decreasing variability in sleep is an easily adjustable lifestyle behaviour that can not only help improve sleep, but can also help reduce cardiovascular disease for ageing adults.’

Poor sleep, including low quality, abnormal quantity and fragmented segments, has already been linked to heart disease, high blood pressure, obesity and type 2 diabetes.

Writing in the Journal of the American Heart Association, the researchers said doctors who encourage their patients to maintain regular sleep patterns can help them reduce their risk of cardiovascular disease.

Data suggests that in the UK, around three million people have atherosclerosis, with increased risks for people who are older, smoke, are overweight or are physically inactive.