Changes in Emergency Department Utilization in Vulnerable Populations After COVID-19 Shelter-in-Place Orders

This study aims to compare emergency department (ED) utilization and admission rates for patients with a history of mental health (MH) disorders, substance use disorders (SUDs), and social determinants of health (SDOH) before and after implementing COVID-19 shelter-in-place (SIP) orders.

This was a retrospective, multicenter study leveraging electronic medical record (EMR) data from 20 EDs across a large Midwest integrated healthcare system from 5/2/2019 to 12/31/2019 (pre-SIP) and from 5/2/2020 to 12/31/2020 (post-SIP). Diagnoses were documented in the patient's medical records. Poisson and logistic regression models were used to evaluate ED utilization and admission rate changes.

A total of 871,020 ED encounters from 487,028 unique patients were captured. Overall, 2,572 (0.53%) patients had a documented Z code for SDOH. Patients with previously diagnosed MH disorders or SUDs were more likely to seek ED care after the SIP orders were implemented (risk ratio (RR): 1.20, 95% confidence interval (CI): 1.18-1.22, p<0.001), as were patients with SDOH (RR: 2.37, 95% CI: 2.19-2.55, p<0.001). Patients with both previously diagnosed MH disorders or SUDs and a documented SDOH had even higher ED utilization (RR: 3.31, 95% CI: 2.83-3.88, p<0.001) than those with either condition alone. Patients with MH disorders and SUDs (OR: 0.89, 95% CI: 0.86-0.92, p<0.001) or SDOH (OR: 0.67, 95% CI: 0.54-0.83, p<0.001) were less likely to be admitted post-SIP orders, while patients with a history of diseases of physiologic systems were more likely to be admitted.

Vulnerable populations with a history of MH disorders, SUDs, and SDOH experienced increased ED utilization but a lower rate of hospital admissions after the implementation of SIP orders. The findings highlight the importance of addressing these needs to mitigate the impact of public health crises on these populations.