LAUSR

Type of funding sources: None. Risk of atherosclerotic cardiovascular disease (ASCVD) attributable to premature ASCVD remains poorly understood. To evaluate the risk of ASCVD among those with premature ASCVD versus those without in a large contemporary population. This observational cohort study included young adults (ages 30-55 years) with and without prior ASCVD (as of January 1, 2006) who were members of an integrated healthcare delivery system in Northern California. Adjusted multivariate models were specified to estimate risk ratios (RRs) for incident ASCVD events by ASCVD status at baseline. Incident ASCVD events were defined as a composite of nonfatal myocardial infarction, ischemic stroke, or coronary heart disease death through December 31, 2020. A total of 929,214 individuals met the selection criteria of no prior ASCVD and 5,703 with prior ASCVD. Mean age was 43.9 (±7.3) years and 50.0 (±5.2) years, respectively. Fifty-two and thirty percent were women in each cohort, and the median follow-up was 11.8 and 8.3 years, respectively. Crude ASCVD rate was 2.1 and 24.5 events per 1,000 person-years, respectively. Age-adjusted Kaplan-Meier curves for ASCVD in individuals with and without prior ASCVD in Figure. In models adjusted for demographics (sex, age, race) and traditional risk factors (diabetes, hypertension, LDL-cholesterol, HDL-cholesterol, total cholesterol, smoking), individuals with prior ASCVD had RR of 4.6 (95% CI 4.3-5.0) for CHD, RR of 3.0 (95% CI 2.7-3.4) for stroke and RR of 4.1 (95% CI 3.8-4.3) for ASCVD. Risk of ASCVD among those with prior ASCVD was several-fold greater compared to those without prior ASCVD. Continued efforts for secondary prevention are needed in this vulnerable high-risk population.