People who suffered from insomnia were 69% more likely to have a heart attack compared to those who did not have the sleep disorder over an average follow-up of nine years, according to new research being presented at the American College of Cardiology’s Annual Scientific Session in conjunction with the World Congress of Cardiology. In addition, looking at sleep duration as an objective measure of insomnia, researchers found that people who clock in five or fewer hours of sleep per night are at the highest risk for a heart attack. People with both diabetes and insomnia were twice as likely to have a heart attack.
Dean and her research team hope the current study will help draw attention to the role that sleep disturbances may play in heart health. Insomnia can include problems falling asleep, staying asleep, or getting good quality sleep. Insomnia is growing in prevalence, affecting an estimated 10% to 30% of American adults, and affecting women more than men. While studies have linked insomnia to cardiovascular and metabolic disease, this analysis is the largest to date.
“Based on our collected data, insomnia should be considered a risk factor for developing a heart attack, and we need to better educate people about how dangerous [lack of good sleep] can be,” said Dean.
For their analysis, the researchers conducted a systematic review of the literature that yielded 1,226 studies — of these, nine studies from the US, UK, Norway, Germany, Taiwan and China were selected for inclusion. Altogether, data from 1,184,256 adults (43% of whom were female) were reviewed. The mean age was 52 years and 13% (153,881) had insomnia, defined by ICD diagnostic codes or by the presence of one of three symptoms: difficulty falling asleep, difficulty staying asleep, or waking early and not being awake. be able to wake up. asleep again. People with obstructive sleep apnea were not included. Most patients (96%) had no history of heart attack. Heart attacks occurred in 2,406 of those who had insomnia and 12,398 of those in the non-insomnia group.
Based on the pooled data, there was a statistically significant association between insomnia and having a heart attack after controlling for other factors that could make a heart attack more likely, such as age, gender, comorbidities and smoking. This association between insomnia and heart attack remained significant in all patient subgroups, including younger and older age (<65 en >65), duration of follow-up (more or less than five years), male and female gender and common comorbidities (diabetes, high blood pressure or cholesterol).
“It’s not surprising that people with insomnia who also had high blood pressure, cholesterol or diabetes had an even higher risk of heart attack than those who didn’t,” Dean said. “People with diabetes who also have insomnia were twice as likely to have a heart attack.”
In addition, people who reported five or fewer hours of sleep per night were 1.38 and 1.56 times more likely to have a heart attack compared to those who slept six and seven to eight hours per night, respectively. There was no difference in heart attack risk between those who got five or less or nine or more hours of sleep per night, Dean said, supporting findings from previous studies that have shown that too little or too much sleep can be harmful to heart health. Dean and her team found that patients who slept six hours had a lower risk of heart attack than those who slept nine hours.
In a separate analysis, the researchers sought to determine whether individual insomnia symptoms are associated with a higher risk of heart attack. Disorders of initiating and maintaining sleep – that is, difficulty falling or staying asleep – were also linked to a 13% increased risk of heart attack compared to people without these symptoms.
However, unrestorative sleep and daytime dysfunction were not associated with heart attack, suggesting that those who only complain that they do not feel refreshed upon waking up without sleep deprivation are not at an increased risk for heart attacks, Dean said.
Based on the findings, Dean said it’s important for people to prioritize sleep so they get seven to eight hours of quality sleep per night.
Practice good sleep hygiene; the room should be dark, quiet, and on the cool side, and put away appliances. Do something calming to unwind, and if you’ve tried all of these things and still can’t sleep or sleeps less than five hours, talk to your doctor.”
The study had some limitations, including that most of the studies reviewed were based on participants self-reporting sleep behavior using questionnaires, although heart attacks were validated by medical reports.