Association of beta-blocker treatment with mortality following myocardial infarction in patients with chronic obstructive pulmonary disease and heart failure or left ventricular dysfunction: a propensity matched-cohort analysis from the High-Risk Myocardial Infarction Database Initiative

Aims: To determine the influence of baseline beta-blocker use on long-term prognosis of myocardial infarction (MI) survivors complicated with heart failure (HF) or with left ventricular dysfunction and with history of chronic obstructive pulmonary disease (COPD). Methods and results: Among the 28 771 patients from the High-Risk MI Database Initiative we identified 1573 patients with a baseline history of COPD. We evaluated the association between beta-blocker use at baseline (822 with beta-blocker and 751 without) on the rates of all-cause and cardiovascular mortality. On univariable Cox analysis, beta-blocker use was found to be associated with lower rates of both all-cause [hazard ratio (HR) = 0.61, 95% confidence interval (CI) 0.51-0.75, P < 0.0001] and cardiovascular mortality (HR = 0.63, 95% CI 0.51-0.78, P < 0.0001). After extensive adjustment for confounding, including 24 baseline covariates, COPD patients still benefited from beta-blocker usage (HR = 0.73, 95% CI 0.60-0.90, P = 0.002 for all-cause mortality; HR = 0.77, 95% CI 0.61-0.97, P = 0.025 for cardiovascular mortality). Adjusting for propensity scores (PS) constructed from the 24 aforementioned baseline characteristics provided similar results. In a cohort of 561 pairs of patients taking or not taking beta-blocker matched on PS using a 1:1 nearest-neighbour matching method, patients treated with beta-blocker experienced fewer all-cause deaths (HR = 0.71, 95% CI 0.56-0.89, P = 0.003) and cardiovascular deaths (HR = 0.76, 95% CI 0.59-0.97, P = 0.032). Conclusions: In the specific setting of a well-treated cohort of high-risk MI survivors, beta-blockers were associated with better outcomes in patients with COPD.