Background: The relative benefits of cardioselective beta-adrenoceptor antagonists (CSB) among patients with congestive heart failure (CHF) and diabetes mellitus are not firmly established.
Objective: To determine whether diabetic patients with CHF accrue the same mortality benefit from CSB therapy as non-diabetic patients.
Method: Between October 1999 and November 2000 consecutive patients with CHF at the Veteran's Affairs Medical Center in Indianapolis, IN, USA, were enrolled in a randomized controlled trial and prospectively followed for 5 years. Disease severity and CHF-specific functional status were obtained from patients at baseline. Medical records were accessed for data regarding co-morbidities, medications, and mortality. Propensity-score analysis was used to balance co-variates because of the observational nature of CSB use, given this was a post hoc analysis. A multivariate Cox proportional hazards model was used to compare survival between diabetic and non-diabetic patients stratified by whether they were or were not receiving CSB therapy.
Results: Of the 412 evaluable patients, 222 (54%) had diabetes and 212 (51%) were taking a CSB. At 5-year follow-up, 186 (45%) patients had died. In the multivariate analysis, using propensity scores to balance co-variates, CSB therapy was an independent predictor of survival in patients without diabetes (hazard ratio 0.60; p = 0.054) only.
Conclusions: These results extend prior observations that patients with diabetes and CHF may not accrue the same mortality benefit from CSB therapy as patients without diabetes, and warrant further prospective investigation.