Cost-effectiveness of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor therapy in older patients with myocardial infarction.

BACKGROUND 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin) therapy has proven efficacy in reducing the rate of coronary and cerebrovascular events in patients 75 years of age or younger with a history of myocardial infarction. However, in patients older than 75 years of age, the efficacy and potential cost-effectiveness of statins are unknown. OBJECTIVE To estimate the incremental cost-effectiveness of statin therapy compared with usual care in patients 75 to 84 years of age with previous myocardial infarction. DESIGN Cost-effectiveness analysis. DATA SOURCES Published data from cohort studies. TARGET POPULATION Patients 75 to 84 years of age with a history of myocardial infarction. TIME HORIZON Lifetime. PERSPECTIVE Societal. INTERVENTION Statin therapy. OUTCOME MEASURES Life expectancy, quality-adjusted life expectancy, and incremental cost-effectiveness. RESULTS OF BASE-CASE ANALYSIS The incremental cost-effectiveness of statin therapy compared with usual care in patients 75 to 84 years of age with previous myocardial infarction was $18800 per quality-adjusted life-year (QALY). RESULTS OF SENSITIVITY ANALYSIS On the basis of a probabilistic sensitivity analysis, there is a 75% chance that statin therapy costs less than $39800 per QALY compared with usual care. If the cost of statin therapy and efficacy of statin therapy at reducing myocardial infarction were set to their most favorable values, statin therapy cost $5400 per QALY; if cost and efficacy were set to their least favorable values, statin therapy cost $97800 per QALY. CONCLUSIONS The cost-effectiveness ratios of statin therapy in older patients with previous myocardial infarction are reasonable under a wide variety of assumptions about drug efficacy, drug cost, and rates of cardiac and cerebrovascular events. Pending results of randomized, controlled trials of secondary prevention in patients in this age group, statin therapy seems to be as cost-effective as many routinely accepted medical interventions in this setting.