Pandemic phase-related racial and ethnic disparities in COVID-19 positivity and outcomes among patients presenting to emergency departments during the first two pandemic waves in the USA

Background: In many countries including the USA, the UK and Canada, the impact of COVID-19 on people of colour has been disproportionately high but examination of disparities in patients presenting to ED has been limited. We assessed racial and ethnic differences in COVID-19 positivity and outcomes in patients presenting to EDs in the USA, and the effect of the phase of the pandemic on these outcomes.

Methods: This is a retrospective cohort study of adult patients tested for COVID-19 during, or 14 days prior to, the index ED visit in 2020. Data were obtained from the National Registry of Suspected COVID-19 in Emergency Care network which has data from 155 EDs across 27 US states. Hierarchical models were used to account for clustering by hospital. The outcomes included COVID-19 diagnosis, hospitalisation at index visit, subsequent hospitalisation within 30 days and 30-day mortality. We further stratified the analysis by time period (early phase: March-June 2020; late phase: July-September 2020).

Results: Of the 26 111 adult patients, 38% were non-Hispanic White (NHW), 29% Black, 20% Hispanic/Latino, 3% Asian and 10% all others; half were female. The median age was 56 years (IQR 40-69), and 53% were diagnosed with COVID-19; of those, 59% were hospitalised at index visit. Of those discharged from ED, 47% had a subsequent hospitalisation in 30 days. Hispanic/Latino patients had twice (adjusted OR (aOR) 2.3; 95% CI 1.8 to 3.0) the odds of COVID-19 diagnosis than NHW patients, after adjusting for age, sex and comorbidities. Black, Asian and other minority groups also had higher odds of being diagnosed (compared with NHW patients). On stratification, this association was observed in both phases for Hispanic/Latino patients. Hispanic/Latino patients had lower odds of hospitalisation at index visit, but when stratified, this effect was only observed in early phase. Subsequent hospitalisation was more likely in Asian patients (aOR 3.1; 95% CI 1.1 to 8.7) in comparison with NHW patients. Subsequent ED visit was more likely in Blacks and Hispanic/Latino patients in late phase.

Conclusion: We found significant differences in ED outcomes that are not explained by comorbidity burden. The gap decreased but persisted during the later phase in 2020.