An individual who gets too much sleep and a person who skimps on sleep are equally at risk of developing heart attack, a study found. According to the research, a physically active, non-smoker may also suffer from this chronic disease due to insufficient sleep or too much sleep.

Irregular sleeping pattern is known to be a leading cause for this cardiovascular disease. Several studies also suggested that insomnia can increase the risk of heart attack. But the latest study shows that people who sleep more than nine hours at night are also at risk of this illness.

The study, published in the Journal of the American College of Cardiology on Monday, focused on the association between sleep duration and myocardial infarction. Through the study, the research team found out that individuals with no genetic predisposition to heart disease may also suffer from this illness due to too much sleep or too little sleep.

The research team also found out that people who are at increased genetic risk of heart attack can prevent this disease by sleeping for six to nine hours regularly at night.

“This provides some of the strongest proof yet that sleep duration is a key factor when it comes to heart health, and this holds true for everyone,” Celine Vetter, who is the senior author and an assistant professor of Integrative Physiology, said in a statement.

For the study, a group of researchers from the University of Manchester and the Massachusetts General Hospital analyzed the data of nearly half a million people that they collected from the UK Biobank.

During the analysis, the team looked into the details about the medical records, self-reported sleeping habits and genetic information of each of the participants. They were aged between 40 and 69 years and none of them had a history of heart attack.

The researchers then followed the participants for seven years. From a total of 461,000 participants, those who slept for over nine hours had a 34 percent increased risk of developing a heart attack than those who slept for six to nine hours at night.

The researcher team also found out that those who slept less than six hours at night had a 20 percent higher risk of heart attack. The study further stated that individuals with a genetic predisposition of this cardiovascular disease lowered their risk by sleeping for six to nine hours per night.

“It’s kind of a hopeful message, that regardless of what your inherited risk for heart attack is, sleeping a healthy amount may cut that risk just like eating a healthy diet, not smoking, and other lifestyle approaches can,” lead researcher Iyas Daghlas, who is a medical student at Harvard, said.

To draw a conclusion, the research team took into consideration 30 other factors that can increase the risk of this chronic disease, like physical activity, body composition, mental health and socioeconomic status.

At the end of the study, the researchers found out that sleep itself is an independent cause for heart attack. For instance, individuals who slept for more than 10 hours at night were twice likely to suffer from this chronic disease than those who slept for six to nine hours a day.

Similarly, people who slept for less than six hours a day had a 52 percent higher risk of developing this cardiovascular disease than those who slept for seven to eight hours a day, the research team noted.

“This gives us even more confidence that there is a causal relationship here—that it is sleep duration, not something else, influencing heart health,” the lead researcher said. “Just as working out and eating healthy can reduce your risk of heart disease, sleep can too,” Vetter added.

In this image, a woman sleeps at Gatwick Airport in southern England, Dec. 7, 2013. CARL COURT/AFP/Getty Images