Understanding the Burden of 30-Day Readmission in Patients With Both Primary and Secondary Diagnoses of Heart Failure: Causes, Timing, and Impact of Co-Morbidities.

Although efforts to reduce 30-day readmission rates have mainly focused on patients with heart failure (HF) as a primary diagnosis at index hospitalization, patients with HF as a secondary diagnosis remain common, costly, and understudied. This study aimed to determine the incidence, etiology, and patterns of 30-day readmissions after discharge for HF as a primary and secondary diagnosis and investigate the impact of co-morbidities on HF readmission. The National Readmission Database from 2014 to 2016 was used to identify HF patients with a linked 30-day readmission. Patient and hospital characteristics, admission features, and Elixhauser-related co-morbidities were compared between the 2 groups. Readmitted patients in both groups were younger, male, with lower household income, higher mortality risk, and higher hospitalization costs. Over 60% of readmissions were for reasons other than HF, and greater than 1/3 had more than 2 readmissions within 30 days, with a median time to readmission of 12 days. Both cohorts had high readmission rates and high rates of readmission for causes other than HF. Our findings suggest that efforts to reduce 30-day readmission rates should be extended to patients with secondary HF diagnosis, with surveillance extending to 2 weeks postdischarge to identify patients at risk.