Validation of the Readmission Risk Score in Heart Failure Patients at a Tertiary Hospital

Background The Readmission Risk score (RR score) is a software application developed to identify patients at increased risk for readmission. This score was developed to improve on the methodology for 30-day risk-standardized all-cause readmission rates (RSRRs) used by the Centers for Medicare and Medicaid Services for its quality reporting system. However, the utility of the RR score in clinical practice has not been independently validated. Methods and Results We included patients admitted with the primary discharge diagnosis of congestive heart failure (CHF) from September 2011 to August 2013. Data on individual components of the RR score were obtained by means of detailed chart review. We calculated the RR score of all admissions and examined its ability to predict 30-day all-cause readmission. We repeated the analysis by randomly selecting 1 admission per patient and also by including only those ≥65 years old. A total of 1,046 admissions met the inclusion criteria. Of these, 369 (35.28%) were readmitted within 30 days of discharge. The performance of the RR score was poor, with an area under the receiver operating characteristic curve (AUC) of 0.61 (95% confidence interval [CI] 0.57-0.64) for all age groups and 0.59 (95% CI 0.53-0.64) for patients aged ≥65 years. The AUC for the RR score was 0.58 (95% CI 0.50-0.65) in a randomly selected patient-level model. However, patients in the highest quartile of RR score were twice as likely to be readmitted as those in the lowest quartile (47.24% vs 24.69%; P <.001). The sensitivity and specificity of the RR score in predicting all cause readmissions were poor. Conclusion Based on our single-institution data, patients with CHF readmitted within 30 days had a higher RR score than those not readmitted. The ability of the RR score to predict future all-cause readmission was modest at best.