Abstract 14768: Contemporary Hospitalization and Thirty-Day Readmission Rates of Unstable Angina in the United States: Insights From Nationwide Readmissions Database 2016-2019

Abstract

Introduction: There are limited data on the contemporary hospitalization rate and 30-day readmission characteristics of unstable angina (UA). Methods: Using Nationwide Readmissions Database from 2016 to 2019, we identified UA hospitalizations based on ICD-10-CM codes and analyzed the rate, trend, timing, causes, and costs of 30-day readmissions after UA in the United States. Multivariable regression analysis was conducted to determine the predictors of 30-day readmission. Results: A total of 498,008 patients were hospitalized with UA, resulting in the in-hospital mortality of 0.4%. During the study period, a significant decrease in the temporal trend of UA hospitalization rate was observed ( Figure 1 ). Among 458,823 patients who were discharged alive, 11.4% were readmitted within 30 days with a median time to readmission of 9 days. There was a significant reduction in the temporal trend of 30-day readmission rate ( Figure 2 ). The most common cause of readmission and procedure during the readmission were recurrent UA and left heart catheterization, respectively. While cardiovascular comorbidities, including congestive heart failure and atrial fibrillation, were associated with an increased likelihood of 30-day readmission, the ischemic evaluation performed during index hospitalization was associated with decreased odds of readmission ( Table ). The mortality during the readmission was 2%. The cumulative costs of hospitalization were $30,729 vs. $14,998 for UA patients with and without readmission, respectively. Conclusions: The index hospitalization and early readmission rates of UA have decreased over time. About 1/10 of UA patients were readmitted within 30 days of discharge, primarily due to recurrent UA. The early readmission may be reduced by a timely ischemic evaluation following UA.