OBJECTIVES: Compare statin adherence, persistence, and health care costs among patients in whom atorvastatin (AS), simvastatin (SS), rosuvastatin (RS), or pravastatin (PS) was newly prescribed. METHODS: Study patients ≥18 years were identified between October 1, 2006-September 30, 2007, with a minimum 12-month pre- and 24-month post-index health plan eligibility from a managed care database. A 6-month washout period free of any statin use was applied to identify patients in whom statin therapy was newly prescribed. The index date was defined as the date of the first statin prescription and four cohorts were created based on index statins: AS, SS, RS, and PS. These cohorts were matched according to propensity scores based on patient clinical and demographic characteristics. Outcomes were compared among matched cohorts during the 2-year post-index period, including adherence to any statin (medication possession ratio≥0.8), time to any statin discontinuation, and health care costs. RESULTS: After matching, 6185 patients were obtained in each cohort and the baseline characteristics were balanced among cohorts. Half of the patients were adherent to their statin therapy at 12 months (52.2% for SS, 47.3% for AS, 48.6% for RS, and 49.7% for PS, P<0.01), with further decline at 24 months (43.1% for SS, 38.0% for AS, 39.2% for RS, and 38.5% for PS, P<0.01). Median time to any statin discontinuation within 24 months were less than 1 year for all cohorts (SS: 308 days; AS: 250 days; RS: 266 days; PS: 301 days, P<0.01). The cohorts had slightly different 2-year health care costs (SS: $15,417; AS: $16,826; RS: $15,874; PS: $15,481, P<0.01) with the most difference attributable to the lower drug costs (SS: $4460; AS: $5485; RS: $5424; PS: $4586, P<0.01). CONCLUSIONS: Patients had low adherence and persistence rates to statin therapy. Patients initiating different statins had varying adherence and persistence profiles, including 2-year health care costs.