Predictors of 1-year mortality in patients with contemporary guideline-adherent therapy after acute myocardial infarction: results from the OMEGA study

Abstract

Background: Predictors of long-term mortality after discharge after acute myocardial infarction (AMI) are well characterized. However, these established risk factors are based on data almost exclusively derived from older studies without consistent use of revascularization therapy and adjunctive therapy with statins, platelet inhibitors, beta-blockers and ACE inhibitors/ARBs. We therefore sought to investigate predictors of 1-year mortality in survivors of AMI treated with contemporary guideline-adherent therapy.

Methods and results: We performed a retrospective analysis of 3,782 patients surviving acute ST-elevation and non ST-elevation myocardial infarction who were enrolled in the prospective, randomized, double-blind, controlled OMEGA trial with 104 German centers. The primary objective of the OMEGA study was to determine the effect of highly purified omega-3 fatty acid ethyl esters-90 on the rate of sudden cardiac death in patients surviving AMI and receiving current guideline-adherent treatment within the 1-year of follow-up. 80.8 % of the patients received early revascularization therapy. At discharge, 94.2 % of the patients received beta-blocker, 90.4 % ACE inhibitor/angiotensin receptor blocker, 94.3 % statin, 95.4 % aspirin and 88.4 % clopidogrel. During the 1-year follow-up 139 patients (3.7 %) died. Multivariate logistic regression analysis revealed the following independent predictors of 1-year mortality in decreasing order of importance: ejection fraction <45 % [odds ratio (OR) 2.28, 95 % confidence interval (CI) 1.53-3.41], age ≥70 years (OR 2.17, 95 % CI 1.42-3.32), no acute revascularization (OR 2.02, 95 % CI 1.33-3.08), prior stroke/transient ischemic attack (OR 1.90, 95 % CI 1.09-3.30), peripheral arterial disease (OR 1.86, 95 % CI 1.12-3.10), heart rate >85/min (OR 1.82, 95 % CI 1.23-2.71), chronic obstructive lung disease (OR 1.77, 95 % CI 1.01-3.10) and HDL cholesterol <40 mg/dl (OR 1.75, 95 % CI 1.15-2.67).

Conclusions: In patients surviving AMI and treated with contemporary guideline-adherent therapy, 1-year mortality was low. Nevertheless, traditional risk factors such as ejection fraction <45 %, older age, no acute revascularization and comorbidities were the strongest predictors of long-term mortality supporting the findings from previous studies.