Insomnia elevates an individual’s chances of suffering major adverse cardiovascular events (MACE), a new study has found.
Data shows that around 50% of heart disease patients experience insomnia – a severe sleep condition that disrupts sleeping patterns, making it difficult for people to fall and stay asleep. Now, new findings suggest that insomnia may significantly increase the risk of major adverse cardiovascular events, a worrying development for the millions of heart disease patients globally.
Lars Frojd, the lead author of the study and a medical student at the University of Oslo, commented: “Sleep problems are linked to mental health issues, but our study found that insomnia was still significantly associated with heart events even after accounting for symptoms of anxiety and depression. The findings suggest that heart patients should be assessed for insomnia and offered appropriate management.”
The study’s results are published in SLEEP Advances.
Investigating insomnia
The team’s study involved 1,068 consecutive patients for an average of 16 months following a heart attack or a procedure to open blocked arteries, such as stent implantation or bypass surgery. In addition, the team collected baseline data on insomnia, risk factors for repeat heart events, and co-existing conditions.
The research participants performed the Bergen Insomnia Scale questionnaire, which comprises six questions based on the diagnostic criteria for insomnia. The questions included the ability to fall asleep and stay asleep, waking up prematurely, feeling inadequately rested, tiredness during the day that affects the ability to function at work or socially, and being dissatisfied with sleep.
The risk factors in the study included C-reactive protein, smoking status, diabetes, low-density lipoprotein (LDL) cholesterol, waist circumference, physical activity, and systolic blood pressure. Moreover, co-existing conditions were stroke, transient ischaemic attack, peripheral artery disease, and kidney failure.
The researchers followed the participants for the primary composite endpoint of major adverse cardiovascular events, which were characterised as cardiovascular death, hospitalisation due to myocardial infarction, revascularisation, stroke or heart failure. Hospital data were employed to acquire outcome data.
41% of the participants were women, and at baseline, the patient’s average age was 62 years, 45% had insomnia, and 24% had used sleep medication within the past week.
Increasing risk of major adverse cardiovascular events
During an average follow-up of 4.2 years, 225 patients experienced 364 major adverse cardiovascular events. In comparison to those without insomnia, the relative risk for recurrent MACE for patients with insomnia was 1.62 after adjusting for age and sex, 1.49 after adjusting for coronary risk factors, and 1.48 after adjusting for co-existing conditions.
Furthermore, the association between recurrent MACE and insomnia was high after adjusting for symptoms of anxiety and depression, generating a relative risk of 1.41. Attributable risk fraction analysis revealed that insomnia accounted for 16% of recurrent major adverse cardiovascular events, smoking being 27%, and low physical activity being 21%.
Frojd concluded: “This means that 16% of recurrent major adverse cardiovascular events might have been avoided if none of the participants had insomnia. Our study indicates that insomnia is common in heart disease patients and is linked with subsequent cardiovascular problems regardless of risk factors, co-existing health conditions and symptoms of mental health. Further research is needed to examine whether insomnia treatments such as cognitive behavioural therapy and digital applications are effective in this patient group.”
