Association between type-2 diabetes mellitus and post-discharge outcomes in heart failure patients: findings from the RICA registry

Abstract

Aims: Heart failure (HF) and diabetes are common clinical conditions that may coexist. The main objective was to analyze the association of type-2 diabetes mellitus (T2DM) on prognosis in hospitalized patients with HF.

Methods: We evaluated the association between T2DM with all-cause mortality and readmissions in the Spanish National Registry on Heart Failure-"Registro Nacional de Insuficiencia Cardiaca" (RICA). This is a multi-center and prospective cohort study that includes patients admitted for decompensated HF from 2008 to 2011. Study endpoints were all-cause mortality and hospital readmission. We determined the adjusted hazard ratio (HR) by a multivariable Cox regression model.

Results: A total of 1082 patients (mean age 77.6±8.5) were included of whom 490 (45.3%) had diabetes and 592 patients (54.7%) had preserved left ventricular ejection fraction (LVEF). During one-year follow-up, 287 patients died (151 patients with diabetes) and 383 patients were readmitted (197 patients with diabetes). After adjusting for baseline characteristics T2DM was significantly associated with all-cause mortality (HR 1.54; 95%CI 1.20-1.97, p=0.001) and readmissions (HR 1.46; 95%CI 1.18-1.80, p<0.001). Age, dementia, peripheral vascular disease, NYHA class, renal insufficiency, hyponatremia and anemia were also independently associated with outcomes. There were no differences in mortality (p=0.415) and readmissions (p=0.514) according to preserved or reduced LVEF.

Conclusion: T2DM is very common in patients hospitalized for HF. This condition is a strong and independent co-morbidity of all-cause mortality and readmission for both HF with preserved and reduced LVEF.

Keywords: Diabetes; Heart failure; Mortality; Prognosis.