Association between diabetes mellitus and post-discharge outcomes in patients hospitalized with heart failure: findings from the EVEREST trial

Aims We evaluated the impact of diabetes mellitus (DM) and diabetic therapy on outcomes in patients with reduced ejection fraction (EF) after hospitalization for heart failure (HF). DM is prevalent in patients hospitalized with HF, yet inconclusive data exist on the post-discharge outcomes of this patient population. Methods and results Post-hoc analysis was performed on the EVEREST (Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan) study, a randomized trial of patients hospitalized with HF (n = 4133) with median follow-up of 9.9 months. DM status was determined from intake questionnaires and cross-verified by medication history. Univariate relationships were examined using χ[2] test, t-test, and Wilcoxon tests. The two primary outcomes of (i) all-cause mortality (ACM) and (ii) cardiovascular mortality or HF hospitalization (CVM + HFH) were assessed for those with and without DM and by diabetic treatment strategy using log rank tests and multivariable Cox regression models. DM was present in 40% of participants. Patients with DM were more likely to have hypertension, coronary artery disease, and chronic kidney disease. Diabetes was associated with ACM and CVM + HFH (both P < 0.001). Following multivariate risk adjustment, DM was associated with ACM, but this estimate was imprecise [hazard ratio (HR) 1.16; 95% confidence interval (CI) 1.00–1.34] and remained associated with CVM or HFH (HR 1.17; 95% CI 1.04–1.31). Diabetic control strategy did not independently affect outcomes. Conclusion Diabetes is common in patients hospitalized for heart failure with a reduced EF. These patients have a higher post-discharge CVM and higher HF hospitalizations compared with patients with no diabetes. Different diabetic treatment regimens did not appear to influence post-discharge outcomes.