Abstract
BACKGROUND: Adherence to pharmacotherapy for heart failure is poor among older adults in part because of high prescription drug costs. We examined the impact of improvements in drug coverage under Medicare Part D on utilization of, and adherence to, medications for heart failure in older adults. METHODS: We used a quasi-experimental approach to analyze pharmacy claims for 6,950 individuals aged >or=65 years with heart failure enrolled in a Medicare managed care organization 2 years before and after Part D's implementation. We compared prescription fill patterns among individuals who moved from limited (quarterly benefits caps of USD 150 or USD 350) or no drug coverage to Part D in 2006 with those who had generous employer-sponsored coverage throughout the study period. RESULTS: Individuals who previously lacked drug coverage filled approximately 6 more heart failure prescriptions annually after Part D (adjusted ratio of prescription counts = 1.36, 95% CI 1.29-1.44, P < .0001 relative to the comparison group). Those previously lacking drug coverage were more likely to fill prescriptions for an angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker plus a beta-blocker after Part D (adjusted ratio of odds ratios = 1.73, 95% CI 1.42-2.10, P < .0001) and more likely to be adherent to such pharmacotherapy (adjusted ratio of odds ratios = 2.95, 95% CI 1.85-4.69, P < .0001) relative to the comparison group. CONCLUSIONS: Medicare Part D was associated with improved access to medications and adherence to pharmacotherapy in older adults with heart failure.