Calcium channel blockers and mortality in elderly patients with myocardial infarction.

BACKGROUND Although calcium channel blockers are a useful therapy in relieving angina, lowering blood pressure, and slowing conduction of atrial fibrillation, growing evidence has cast doubt on their safety in patients with coronary disease. OBJECTIVE To examine the association between calcium channel blocker therapy at hospital discharge and mortality in a population-based sample of elderly patients hospitalized with acute myocardial infarction. DESIGN Retrospective cohort study using data from medical charts and administrative files. SETTING All acute care hospitals in 46 states. PATIENTS All Medicare patients with a principal diagnosis of acute myocardial infarction consecutively discharged from the hospital alive during 8-month periods between 1994 and 1995 (N = 141,041). MAIN OUTCOME MEASURE Mortality at 30 days and 1 year. RESULTS Calcium channel blockers were widely prescribed at hospital discharge to elderly patients with myocardial infarction between 1994 and 1995 (n = 51,921), the most commonly prescribed being diltiazem (n = 21,175), nifedipine (n = 12,670), amlodipine (n = 11,683), and verapamil (n = 3639). After adjusting for illness severity and concomitant medication use, patients who were prescribed calcium channel blockers at hospital discharge did not have increased risk for 30-day or 1-year mortality, with the exception of the few (n = 116) treated with bepridil. Bepridil differs from other calcium channel blockers because of its tendency to prolong repolarization, and its association with proarrhythmic effects in elderly patients. CONCLUSION We did not identify a mortality risk in a large consecutive sample of elderly patients with myocardial infarction, which supports the need for additional prospective trials examining calcium channel blocker therapy for ischemic heart disease.