Impact of combined secondary prevention therapy after myocardial infarction: data from a nationwide French registry

Abstract

Background: Several classes of medications improve survival in patients with coronary artery disease. Whether these medications, as used in the real world, have additive efficacy remains speculative.

Objectives: To assess whether patients discharged on combined secondary prevention medications after acute myocardial infarction (AMI) have improved 1-year survival, compared with the action of any single class of medications.

Design and setting: Nationwide registry of consecutive patients admitted to intensive care units for AMI in November 2000 in France. Multivariate Cox regression analysis, including a propensity score for the prescription of combined therapy, was used.

Results: Of the 2119 patients discharged alive, 1095 (52%) were prescribed a combination of antiplatelet agents, beta-blockers, and statins (triple therapy), of whom 567 (27%) also received angiotensin-converting enzyme inhibitors (quadruple therapy) and 528 (25%) did not. One-year survival was 97% in patients receiving triple combination therapy versus 88% in those who received either none, 1, or 2 of these medications (P < .0001). After multivariate adjustment including the propensity score, the hazard ratio for 1-year mortality in patients with triple combination therapy was 0.52 (95% CI 0.33-0.81). In patients with ejection fraction < or = 35%, beta-blockers and angiotensin-converting enzyme inhibitors were independent predictors of survival, and combination therapy had no additional prognostic value.

Conclusions: Compared with the prescription of any single class of secondary prevention medications, combination therapy offers additional protection in patients with AMI.