Burden and predictors of thirty-day readmission in patients with NSTEMI: a retrospective analysis of the 2020 NRD database.

Background: Non-ST-segment elevation myocardial infarction (NSTEMI) is an entity which was defined as a type of a coronary syndrome with positive cardiac biomarker of myocardial necrosis with no ST-segment elevation in ECG. Currently, the centers for Medicare and Medicaid services (CMS) Hospital readmission reduction program assistance risk-adjusted 30-day readmission rates for five major clinical entities which includes acute myocardial infarction.

Methods: We performed this retrospective study to look into the current burden and predictors of NSTEMI readmission. Data were obtained from the Nationwide Readmission Database for the year 2020. We analyzed data on hospital readmission of 336 620 adults who were admitted for NSTEMI.

Results: The 30-day readmission rate was 13.5% with NSTEMI being the most common cause of readmission. Mortality was higher in readmitted patients compared to index admission (5.4 vs 3.6%, P = 0.000). Higher risk of readmission was associated with female sex, higher Charlson comorbidity index, and longer length of stay. Lower risk of admission was seen in patients from smaller communities, patients who underwent percutaneous coronary intervention, and discharged to rehabilitation facilities.

Conclusion: Although we found an improvement in readmission rates compared to prior studies, about 13% of patients continue to get readmitted within 30 days causing significant cost to the healthcare system and often these patients have worse outcomes. We need continuing large-scale studies to identify quality measures to prevent readmission, improve mortality during readmission, and make better use of financial resources.