Insomnia is the most prevalent sleep problem, yet in many respects, it is more of a lifestyle choice than a disease. We simply don’t value sleep as much as we should.
A study published online in Clinical Cardiology found that those with insomnia had a 69% higher risk of having a heart attack compared to people without the sleep issue during an average of nine years of follow-up.
Researchers also discovered that persons who slept for five hours or less each night had the highest risk of having a heart attack when using sleep length as an objective indicator of insomnia. The risk of suffering a heart attack was increased threefold among those who both had diabetes and insomnia.
“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 prioritize sleep as much as we should,” points out author Yomna E. Dean.
The findings of the new “study showed that people with insomnia are more likely to have a heart attack regardless of age, and heart attacks occurred more often in women with insomnia.”
Dean and her research group are hoping that this study will raise awareness of the potential link between sleep disturbances and cardiovascular health. Insomnia may manifest as difficulty falling asleep, staying asleep, or receiving enough quality sleep. According to estimates, 10% to 30% of American people suffer from insomnia, with women being more affected than males. There have been studies that show a link between insomnia and heart and metabolic diseases, but this is the largest one to date.
“Based on our pooled data, 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 remarks.
For their study, the researchers performed a comprehensive literature review that generated 1,226 papers; of these, nine studies from the United States, United Kingdom, Norway, Germany, Taiwan, and China were chosen for inclusion. A total of 1,184,256 individuals’ data were evaluated, with 43% of them being women.
The average age was 52, and 13% of people (153,881) had insomnia, which was defined by ICD diagnostic codes or by having any of these three symptoms: trouble falling asleep, trouble staying asleep, or waking up early and not being able to go back to sleep.
None of the participants had obstructive sleep apnea. 96% of patients had no previous history of heart attacks. 2,406 people with insomnia and 12,398 people without insomnia had heart attacks.
After adjusting for other variables that might increase the risk of a heart attack, such as age, gender, comorbidities, and smoking, the pooled data revealed a statistically significant correlation between having insomnia and experiencing a heart attack.
All patient subgroups, including younger and older age (<65 and >65), follow-up period (more or less than five years), male and female sex, and common comorbidities showed a substantial connection between sleeplessness and heart attack (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,” adds Dean. “People with diabetes who also have insomnia had a twofold likelihood of having a heart attack.”
Additionally, compared to individuals who slept six and seven to eight hours a night, respectively, those who reported getting five or fewer hours of sleep each night were 1.38 and 1.56 times more likely to have a heart attack.
Dean said that the risk of a heart attack was the same for people who slept five hours or less or nine hours or more each night. This backs up what other studies have found, which is that getting too little or too much sleep is bad for heart health.
Dean and her team found that people who slept for six hours instead of nine hours were less likely to have a heart attack.
The researchers also looked at various insomnia symptoms to see whether they were linked to an increased risk of a heart attack. Sleep disorders, like having trouble falling asleep or staying asleep, were also linked to a 13% higher risk of heart attack compared to people who didn’t have these symptoms.
Non-restorative sleep and daytime dysfunction, on the other hand, were not linked to heart attacks. This means that people who only say they feel tired when they wake up but haven’t been getting enough sleep aren’t at a higher risk of having a heart attack, according to the author.
Dean concluded that individuals should make sleep a priority in order to acquire seven to eight hours of quality sleep every night.
The author advised to “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.”
While heart attacks were verified by medical records, the research had certain limitations, such as the fact that the majority of the studies evaluated depended on participants’ self-reporting of sleep patterns using questionnaires.
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