Health and economic benefits of increased β-blocker use following myocardial infarction

Context: β-Blockers are underused in patients who have myocardial infarction (MI), despite the proven efficacy of these agents. New evidence indicates that β-blockers can have benefit in patients with conditions that have been considered relative contraindications. Understanding the consequences of underuse of β-blockers is important because of the implications for current policy debates over quality-of-care measures and Medicare prescription drug coverage. Objective: To examine the potential health and economic impact of increased use of β-blockers in patients who have had MI. Design and Setting: We used the Coronary Heart Disease (CHD) Policy Model, a computer-simulation Markov model of CHD in the US population, to estimate the epidemiological impact and cost-effectiveness of increased β-blocker use from current to target levels among survivors of MI aged 35 to 84 years. Simulations included 1 cohort of MI survivors in 2000 followed up for 20 years and 20 successive annual cohorts of all first-MI survivors in 2000-2020. Mortality and morbidity from CHD were derived from published meta-analyses and recent studies. This analysis used a societal perspective. Main Outcome Measures: Prevented MIs, CHD mortality, life-years gained, and cost per quality-adjusted life-year (QALY) gained in 2000-2020. Results: Initiating β-blocker use for all MI survivors except those with absolute contraindications in 2000 and continuing treatment for 20 years would result in 4300 fewer CHD deaths, 3500 MIs prevented, and 45000 life-years gained compared with current use. The incremental cost per QALY gained would be $4500. If this increase in β-blocker use were implemented in all first-MI survivors annually over 20 years, β-blockers would save $18 million and result in 72000 fewer CHD deaths, 62000 MIs prevented, and 447000 life-years gained. Sensitivity analyses demonstrated that the cost-effectiveness of β-blocker therapy would always be less than $11000 per QALY gained, even under unfavorable-assumptions, and may even be cost saving. Restricting β-blockers only to ideal patients (those without absolute or relative contraindications) would reduce the epidemiological impact of β-blocker therapy by about 60%. Conclusions: Our simulation indicates that increased use of β-blockers after MI would lead to impressive gains in health and would be potentially cost saving.