Association between depression and readmission of heart failure: A national representative database study.

INTRODUCTION: Depression is a recognized predictor of adverse outcomes in patients with heart failure (HF) and is associated with poor quality of life, functional limitation, increased morbidity and mortality, decreased adherence to treatment, and increased rehospitalization. To understand the impact of depression on HF readmission, we conducted a retrospective cohort study using the Nationwide Readmission Database (NRD) 2010-2014. METHODS: We identified all patients with the primary discharge diagnosis of HF by ICD-9-CM codes. The primary outcome of the study was to identify 30-day all-cause readmission and causes of readmission in patients with and without depression. Multivariate Cox regression analysis was used to estimate the adjusted hazard ratio for the primary and secondary outcomes. RESULTS: Among, 3,500,570 patients admitted with HF, 9.7% had concomitant depression. Patients with depression were more likely to be readmitted within 30 days (19.7% vs. 18.5%; P < 0.001). Concomitant depression was associated with higher risk of all-cause readmissions within 30 days and 90 days [P < 0.001] but was not associated with increased readmissions due to cardiovascular (CV) cause at 30 days and 90 days. The hazard of psychiatric causes of readmission was higher in patients with depression, both at 30 days [P < 0.001], and 90 days [P < 0.001]. Most of the readmissions were due to CV causes, with HF being the most common cause. CONCLUSION: Among patients hospitalized with HF, the presence of depression is associated with increased all-cause readmission driven mainly by psychiatric causes but not CV-related readmission. Standard interventions targeted toward HF are unlikely to modify this portion of all-cause readmission.