Predictors of 90-Days Readmissions for New Onset Heart Failure after Acute Coronary Syndrome

Abstract

Background Coronary heart disease is one of the leading risk factors for the development of heart failure (HF). Despite major improvements in the management of acute coronary syndromes (ACS), HF remains the most common cause of readmission after ACS, followed by myocardial re-infarction. We sought to evaluate the risks and predictors for HF admission after ACS. Methods Using the national readmission database (NRD), we examined discharge data from 2010 until 2015 and identified all patients age 18 years and older with ACS recorded as the primary discharge diagnosis; we then excluded all patients with a prior diagnosis of HF. Chi-square test and Wilcoxon rank-sum test were used to compare proportions and continuous variables, respectively. We used logistic regression modeling to estimate the unadjusted odds of readmission for the covariates of interest. Results We identified 1,322,335 patients discharged after an ACS (36.2% STEMI). Of these, 56,345 (4.2%) were readmitted within 90-days with a new primary diagnosis of HF. The most common individual risk factors associated with HF admission were the presence of atrial fibrillation (OR 1.71), diabetes (OR 1.62) and lung disease (OR 1.49). The most common predictors for HF admission were STEMI (OR 1.28), development of acute kidney injury (AKI) (OR 1.49), length of stay > 5 days (OR 1.77) and discharge against medical advice (OR 1.88). Revascularization during index admission for ACS was a strong predictor against HF admission (OR of 0.61 and 0.49 for PCI and CABG respectively). Self-pay or private insurance were also associated with lower rates of HF admissions (OR 0.68 and 0.57, respectively). Conclusions Readmission for new-onset HF occurs in close to 5% of patients after ACS. The presence of atrial fibrillation, diabetes, development of AKI or prolonged hospitalization identifies a higher risk cohort at the time of discharge.