The Average Effect of Emergency Department Admission on Readmission and Mortality for Older Adults With Chest Pain

BACKGROUND: Many older adults (65+) present to the Emergency Department (ED) with chest pain, but do not have otherwise clear clinical indication of whether they should be admitted or discharged. This uncertainty leads to decisions that are highly variable-in addition to already being costly-which could have adverse consequences, since older adults are particularly vulnerable from hospitalization. OBJECTIVE: The objective of this study was to determine whether admitting versus discharging an older adult presenting to the ED with chest pain reduces risk of mortality and readmission. STUDY DESIGN: Electronic health records were curated from an academic hospital system between January 1, 2014, and September 27, 2018. Average effects of admission on 30-day readmission and mortality were estimated using a new causal inference approach based on a latent-variable model of the admission process. Additional analyses assessed moderators and robustness of estimates. SUBJECTS: Older patients (n=3090) presenting to University of Wisconsin Hospital ED. MEASURES: Readmission and mortality within 25, 30, and 35 days of discharge from the ED for discharged patients or the hospital for admitted patients RESULTS:: For older chest pain patients, admission is estimated to lower the 30-day risk of readmission by 42.8% (95% confidence interval: 41.0%-44.6%) but increase the 30-day risk of mortality by 0.8% (95% confidence interval: 0.4%-1.2%). Individuals with higher hierarchical conditional category scores or diabetes with complications have both lower 30-day risk of readmission and higher 30-day risk of mortality compared with their counterparts (P≤0.02). CONCLUSIONS: Our findings suggest ED admission may prevent readmission at the cost of increasing mortality risk for older chest pain patients, especially those with comorbidity. Additional studies are needed to validate these findings.