Abstract
BACKGROUND: Heart failure (HF) and diabetes mellitus (DM) often co-exist. Treatment of DM in HF patients is challenging because some therapies for DM are contraindicated in HF. Although previous experimental studies have reported that dipeptidyl peptidase-4 (DPP-4) inhibitors improve cardiovascular function, whether DPP-4 inhibition improves mortality of HF patients with DM remains unclear. Therefore, we examined the impact of DPP-4 inhibition on mortality in hospitalized HF patients using propensity score analyses. METHODS AND RESULTS: We performed observational study analysed by propensity score method with 962 hospitalized HF patients. Of these patients, 293 (30.5%) had DM, and 122 of these DM patients were treated with DPP-4 inhibitors. Propensity scores for treatment with DPP-4 inhibitors were estimated for each patient by logistic regression with clinically relevant baseline variables. The propensity-matched 1:1 cohorts were assessed based on propensity scores (DPP-4 inhibitors, n = 83, and non-DPP-4 inhibitors, n = 83). Kaplan-Meier analysis in the propensity score-matched cohort demonstrated that cardiac and all-cause mortality was significantly lower in the DPP-4 inhibitor group than in the non-DPP-4 inhibitor group (cardiac mortality: 4.8% vs. 18.1%, P = 0.015; all-cause mortality: 14.5% vs. 41.0%, P = 0.003, by a log-rank test). In the multivariable Cox proportional hazard analyses, after adjusting for other potential confounding factors, the use of DPP-4 inhibitors was an independent predictor of all-cause mortality (pre-matched cohort: hazard ratio 0.467, P = 0.010; post-matched cohort: hazard ratio 0.370, P = 0.003) in HF patients with DM. CONCLUSIONS: Our data suggest that DPP-4 inhibitors may improve cardiac and all-cause mortality in hospitalized HF patients with DM.