Heart failure due to systolic dysfunction and mortality in diabetes: pooled analysis of 39,505 subjects

Abstract

Background: Despite recent successes in improving mortality from congestive heart failure (CHF) with drugs and devices, several reports suggest increased mortality among CHF subjects with diabetes. Our objective was to conduct a meta-analysis to determine aggregate risk of mortality and hospitalization in CHF from systolic dysfunction and diabetes.

Methods and results: Observational and randomized trials reporting on CHF and mortality in diabetes since 2001 were identified through MEDLINE and Cochrane database searches and hand searching of cross-references. Minimum follow-up of the study cohort should have been at least 6 months. Studies with very small sample size (n < 200) were excluded. Major outcome measure of mortality and secondary outcome measure of CHF hospitalization were extracted from published results. Analysis was done for composite mortality and hospitalization risk, heterogeneity, robustness, and publication bias. A total of 17 trials (n = 39,505 subjects) were eligible. There were a total of 10,068 deaths, with 3615 among diabetics, from available data. The relative risk was significantly higher for diabetics by 28% (95% CI 1.22-1.34, P < .0001). Similarly pooled relative risk for hospitalization was significantly higher for diabetics by 36% (95% CI 1.26-1.48, P < .0001). Heterogeneity was present (P < .01) and accounted for by observational studies. There was no significant publication bias and lack of robustness was not obvious.

Conclusions: Aggregate mortality and recurrent hospitalization risk for diabetic subjects with CHF is 28% and 36% higher than for nondiabetic subjects. Future trials should specifically focus on improving survival in these subjects.