Insomniacs at greater risk of heart attack: Study

People who suffer from insomnia were 69 per cent more likely to have a heart attack compared to those who do not have the sleep disorder, according to new research.

Researchers from the Alexandria University in Egypt found that people who slept five or less hours a night were 1.38 and 1.56 times more likely to experience a heart attack compared with those who slept six and seven to eight hours a night, respectively.

"Insomnia is the most common sleep disorder, but in many ways it's no longer just an illness, it's more of a life choice. We just don't prioritise sleep as much as we should," said Yomna E. Dean, a medical student at the University.

Insomnia may include trouble falling asleep, staying asleep, or getting good quality sleep.

The study, published online in the journal Clinical Cardiology, stressed that "insomnia should be considered a risk factor for developing a heart attack, and we need to do a better job of educating people about how dangerous (lack of good sleep) can be", Dean said.

For their analysis, the researchers conducted a systematic review of the literature that yielded 1,226 studies and of these, nine studies originating from the US, UK, Norway, Germany, Taiwan and China were selected for inclusion.

The team assessed data for 1,184,256 adults. The association between insomnia and heart attack remained significant across all subgroups of patients, including younger and older age, follow-up duration (more or less than five years), male and female sex, and common comorbidities (diabetes, high blood pressure or cholesterol).

"Not surprisingly, people with insomnia who also had high blood pressure, cholesterol or diabetes had an even higher risk of having a heart attack than those who didn't," Dean said. "People with diabetes who also have insomnia had a two-fold likelihood of having a heart attack."

In a separate analysis, the researchers found that disorders of initiating and maintaining sleep -- that is, trouble falling or staying asleep -- were also tied to a 13 per cent increased likelihood of heart attack compared with people without these symptoms.

"Practice good sleep hygiene; the room should be dark, quiet and on the cooler side, and put away devices. Do something that is calming to wind down, and if you have tried all these things and still can't sleep or are sleeping less than five hours, talk with your doctor," Dean said.