INTRODUCTION: Atherosclerotic cardiovascular disease pathogenesis begins in early adulthood, yet guidance on statin use for primary prevention in young adults is limited. METHODS: This is a retrospective multicenter cohort study of adults aged 20-39 years receiving primary care within 87 U.S. health systems (2022-2023). The study included patients with at least 1 low-density lipoprotein cholesterol (LDL-C) measurement. The primary outcome was the measured the proportion of patients prescribed a statin within 1 month of LDL-C testing. The characteristics of those who were and were not prescribed statins were compared using standardized mean differences. Finally, the PREVENT 10- and 30-year ASCVD risk scores for the "average" patient (using the cohort mean values of risk score variables), a "lower-risk" patient, and a "higher-risk" patient were compared (using pooled values 1 SD below and above the mean, respectively). Analyses were conducted in 2024-2025. RESULTS: Statins were initiated in 3,309 of 775,162 patients. Those who received statins were more likely to be older, male, and have higher mean LDL-C, systolic blood pressure, HgA1c, and BMI (standardized mean differences >
0.10). PREVENT 10-year risk scores were similar or higher among those prescribed statins compared to those not prescribed statins for the average (0.75% vs 0.76%), lower-risk (0.19% vs 0.35%), and higher-risk (8.87% vs 4.55%) groups. CONCLUSION: In a multicenter cohort, 0.43% of young adults were prescribed a statin within 1 month of initial LDL-C measurement. The average patient would not have qualified for statin therapy based on their PREVENT risk percentile. Future studies should evaluate the cost effectiveness of statins for primary prevention in patients aged 20 to 39 years.