This study is one of the first to offer proof of a link between irregular sleep duration and irregular sleep timing and atherosclerosis.

Irregular sleeping patterns may increase the risk of “hardened” arteries in older adults, suggests a new study.

Atherosclerosis may be more likely to develop in people who sleep at irregular times during the week or get inconsistent amounts of sleep at night, according to research.

Plaque, which is a buildup of fatty deposits on the walls of our arteries, causes the condition.

This plaque can either cause blood clots to form that block the artery, causing a heart attack or stroke, or it can cause arteries to narrow, decreasing blood flow and the amount of oxygen and other nutrients reaching the body.

Over 2,000 adults from around the US were followed by researchers for three years, with an average age of 69, in a research project published in the Journal of the American Heart Association – an open access, peer-reviewed journal of the American Heart Association.

They found participants were 40% more likely to have high levels of hardened plaque in their arteries if their sleep duration varied by more than two hours over the course of a week.

Additionally, the individuals had a 12% higher risk of developing fatty plaque in their neck arteries and a 20% higher risk of receiving abnormal atherosclerosis test results.

“This study is one of the first investigations to provide evidence of a connection between irregular sleep duration and irregular sleep timing and atherosclerosis,” said study lead author Kelsie Full in a press release.

The participants kept a seven-day sleep diary in addition to wearing a wrist device that could tell when they were awake and asleep between 2010 and 2013. Additionally, participants participated in a one-night in-home sleep study to detect breathing problems, sleep stages, waking up after falling asleep, and heart rate issues.

Sleep timing was described as the time a person typically falls asleep at night, whereas sleep duration was defined as the total amount of time spent in bed fully asleep.

Heart disease, hypertension, obesity, Type 2 diabetes, and other conditions related to cardiovascular disease are all associated with poor sleep, which includes low quality, abnormal quantities, and fragmented types of sleeping.