PCV24: BEYOND THE FIRST YEAR: PATTERNS AND PREDICTORS OF LONG-TERM STATIN UTILIZATION

INTRODUCTION: Noncompliance with lipid-lowering medications has important implications for clinical and economic outcomes of therapy. Little is known about long-term utilization of HMG Co-A reductase inhibitors (statins) because previous data have been based on closely monitored trials or have observed patients for short periods of time. OBJECTIVE: To describe patterns and predictors of long-term compliance with statin therapy in a US elderly population. METHODS: Cohort study (n = 607) of enrollees in the New Jersey Medicaid and Pharmacy Assistance for the Aged and Disabled (PAAD) programs aged 65 and older who began statin therapy in the first half of 1990. Filled prescription data were used to assess the proportion of days with any statin available in each of 12 consecutive 6-month intervals after initiation of therapy. Demographic and clinical predictors of noncompliance, measured at baseline, were identified using linear models for repeated measures. RESULTS: Mean days with statin available was 64% in the first 6 months of therapy and 45% in the next 6 months; it then decreased linearly to 32% at the end of year 6. The proportion of patients with 80% of days covered was 41% in the first 6 months, 30% in the next 6 months, and 25% at the end of year 6. After controlling for baseline demographic and clinical variables, lower compliance in years 2 through 6 was significantly associated with duration of treatment, black race, lower income, older age, and taking fewer other medications. By contrast, first-year compliance was significantly better among blacks than other races and age was not associated with utilization. CONCLUSIONS: Compliance with statin therapy declines over time, with the greatest reductions occurring in the first year of treatment. Predictors of short- and long-term compliance differ, with long-term noncompliance most strongly predicted by age, race, and socioeconomic status.