If you go to bed and wake up at different times throughout the week — or if your sleep gets disrupted during the night — you could face a higher risk of heart disease, according to a new study published by the American Heart Association.
The study looked at 2,032 older adults, measuring both the duration and timing of their sleep.
For a seven-day period, participants kept a sleep diary and wore a special wristwatch that tracked their sleep quality by measuring movements and oxygen levels.
Those who had irregular sleep patterns — including differences in the times they went to bed and interruptions in their sleep throughout the night — were more likely to show signs of atherosclerosis.
Atherosclerosis, also known as coronary artery disease, is a “thickening or hardening of the arteries caused by a buildup of plaque in the inner lining of an artery,” as defined on Johns Hopkins Medicine’s website.
Researchers adjusted for outside factors, including prior cardiovascular disease, obstructive sleep apnea and other sleep disorders.
“Sleep irregularity, particularly sleep duration irregularity, was associated with several measures of subclinical atherosclerosis,” the study authors wrote.
“Sleep regularity may be a modifiable target for reducing atherosclerosis risk.”
The study was led by Dr. Kelsie M. Full from Vanderbilt University Medical Center, along with researchers from Harvard Medical School, the Johns Hopkins School of Medicine and other institutions.
It was part of the Multi-Ethnic Study of Atherosclerosis (MESA), which involved more than 6,000 men and women from six U.S. communities.
Dr. Pranav Patel, a board-certified cardiologist with Inspira Medical Group Cardiology in New Jersey, said this study is different from the many others that have previously linked sleep deprivation to adverse heart issues.
“What’s novel about this study is that the group of people includes all races. Prior to the 2000s, most studies generally looked at Caucasian males,” he said in a discussion with Fox News Digital.
Patel was not involved in the study.
Among those whose sleep patterns varied by two hours or more each day, the study found an increase of coronary artery disease.
“That essentially means they are more likely to have plaque in the vessels of the heart, which supply the muscle that’s used to pump blood to the rest of the body,” Dr. Patel said.
“This study also showed there was an increase of plaque buildup in the extremities” — the arms and legs — “which we call peripheral vascular disease,” he went on.
Disruptions to the sleep cycle, he added, can lead to increased inflammation and higher blood pressure, which can trigger fatty buildup in the arteries.
“When you’re sleeping, you’re calm and your blood pressure is probably not spiking, but when you’re awake, your blood pressure is more heightened because you have to function and do most of your daily tasks,” he said.
“It all goes back to the circadian rhythm, which is a natural sleep-wake cycle that most people have. People with irregular sleep patterns have a disruption in this cycle — which leads to the increase in inflammation and blood pressure.”
Dr. Patel said the study removed risk factors such as diabetes and previous high blood pressure, looking only at sleep irregularity — “a novel finding that hasn’t been presented until now.”
To achieve a more regular sleep pattern, Dr. Patel recommends setting a bedtime that’s within the same 30-minute window each night.
Those who have problems with snoring or sleep apnea should see a doctor for treatment, he said.
The study authors noted that more research is needed to explore ways to reduce the risk caused by sleep irregularity.
Fox News Digital reached out to the lead author for comment.