Etiologies, Trends, and Predictors of 30-Day Readmission in Patients With Heart Failure.

Heart failure (HF) is the most common discharge diagnosis across the United States, and these patients are particularly vulnerable to readmissions, increasing attention to potential ways to address the problem. The study cohort was derived from the Healthcare Cost and Utilization Project's National Readmission Data 2013, sponsored by the Agency for Healthcare Research and Quality. HF was identified using appropriate International Classification of Diseases, Ninth Revision, Clinical Modification codes. Readmission was defined as a subsequent hospital admission within 30 days after discharge day of index admission. Readmission causes were identified using International Classification of Diseases, Ninth Revision , codes in primary diagnosis filed. The primary outcome was 30-day readmission. Hierarchical 2-level logistic models were used to evaluate study outcomes. From a total 301,892 principal admissions (73.4% age ≥65 years and 50.6% men), 55,857 (18.5%) patients were readmitted with a total of 64,264 readmissions during the study year. Among the etiologies of readmission, cardiac causes (49.8%) were most common (HF being most common followed by coronary artery disease and arrhythmias), whereas pulmonary causes were responsible for 13.1% and renal causes for 8.9% of the readmissions. Significant predictors of increased 30-day readmission included diabetes (odds ratio, 95% confidence interval, p value: 1.06, 1.03 to 1.08, p