OBJECTIVES:  Despite the well-documented efficacy of statins in primary and secondary prevention of cardiovascular disease, adherence to statins remains suboptimal, compromising potential effectiveness. The Centers for Medicare and Medicaid Services (CMS) utilizes the proportion of days covered (PDC) as a measure for medication adherence, with a PDC > 80% considered optimal. PDC provides a single value to represent a follow-up period but cannot fully capture variations in adherence behavior patterns. These patterns should be considered when designing interventions, as they may influence prognosis. Our objective was to characterize different adherence patterns using group-based trajectory models among statin users in a MAP. METHODS:  This project utilized data from a Texas MAP. Patients enrolled from January 2013 to June 2016 with prescription claims were included. The index date was defined as the first statin prescription between January to June 2015, and baseline characteristics were determined from the period 2 years prior to index. Patient adherence was assessed for 1 year after. Monthly PDCs were calculated during the follow-up and dichotomized as adherent (PDC >0.8) or not. Twelve monthly PDC values were then modeled as a longitudinal response in logistic group-based trajectory models. Patients were assigned to a trajectory based on those models. We estimated between 2 to 6 groups for evaluation. RESULTS: