Associations of multi-trajectories of smoking, alcohol use, and physical activity with cardiovascular and cerebrovascular disease risk in Korean adults: A nationwide matched case-control study

OBJECTIVE: To identify multi-trajectories of smoking, alcohol use, and physical activity before diagnosis and examine their associations with overall and subtype-specific cardiovascular and cerebrovascular disease risk. METHODS: This matched case-control study used National Health Insurance Service data from South Korea for adults aged 30-69 years screened in 2015-2016. Cases had a first cardiovascular or cerebrovascular disease admission during 2017-2022; controls were matched on sex, age, and insurance premium quantile. Six-year preindex trajectories of smoking, alcohol use, and physical activity were identified using group-based multi-trajectory modeling, with associations estimated by conditional logistic regression. RESULTS: Among 241,163 cases and 865,065 controls, five groups were identified. Compared with the Low-smoking inactive group, the Smoking-dominant and Heavy-smoking low-activity groups had higher odds of acute myocardial infarction (OR 1.81, 95% CI 1.73, 1.88; OR 2.58, 95% CI 2.46, 2.70, respectively). The Alcohol-prominent group had higher odds of intracranial hemorrhage (OR 1.19, 95% CI 1.12, 1.27), whereas the Low-smoking active group had lower odds of cerebral infarction (OR 0.88, 95% CI 0.84, 0.92). CONCLUSIONS: Multi-trajectory patterns of health behaviors identified a high-risk minority before diagnosis and revealed subtype-specific risk patterns. Screening-based behavioral information may support population-level risk stratification and targeted prevention.