Healthy lifestyle factors, cardiovascular comorbidities, and the risk of sudden cardiac arrest: A case-control study in Korea

Aims: We investigated the impact of healthy lifestyle factors and cardiovascular comorbidities for sudden cardiac arrest. Methods: A case-control study, including patients with sudden cardiac arrest aged 20–79 years and community-based 1:2 matched controls, was conducted from September 2017 to December 2020. All participants completed a structured questionnaire. Using multivariable logistic regression, we assessed cardiovascular comorbidities (diabetes, hypertension, dyslipidaemia, myocardial infarction, congestive heart failure, arrhythmia, and stroke) and healthy lifestyle factors (low red meat consumption, low fish consumption, high fruit consumption, high vegetable consumption, current non-smoking, regular exercise, and adequate sleep duration) as sudden cardiac arrest risk factors. Results: Among 3027 eligible cases, informed consent was obtained from 949 (31.3%) cases. A total of 1731 controls were enrolled. Cardiovascular comorbidities, except dyslipidaemia, were associated with an increased risk of sudden cardiac arrest, whereas all healthy lifestyle factors were associated with a decreased risk. Relative to patients in the 0–2 healthy lifestyle factors group, the adjusted odds ratio (95% confidence interval) for sudden cardiac arrest was 0.25 (0.16–0.40) in patients with 3 healthy lifestyle factors, 0.08 (0.05–0.13) in patients with 4 healthy lifestyle factors, and 0.04 (0.03–0.06) in patients with over 5 healthy lifestyle factors. When the number of healthy lifestyle factors was analysed as a continuous variable, each additional factor was associated with a significant decrease in the likelihood of sudden cardiac arrest (adjusted odds ratio [95% confidence interval]: 0.41 [0.36–0.46]). Conclusion: The increased risk of sudden cardiac arrest by cardiovascular comorbidities could be significantly reduced with healthy lifestyle factors.