Ethnic disparities, clinical severity and their relation to COVID-19 outcomes

Ethnic inequalities in COVID-19 outcomes are extensively documented, yet underlying causes remain unclear. We investigated ethnic disparities in clinical severity at admission with COVID-19 and their relation to mechanical ventilation (MV), 60-day mortality, and long COVID.

Retrospective cohort study of adults (≥18 years) admitted with COVID-19 (March 2020-March 2022). Clinical and sociodemographic data extracted from patient records were linked to national register data. Using logistical regression, competing risk, and Cox proportional hazards models, we estimated risk of high-flow oxygen upon admission, MV, 60-day mortality, and long COVID comparing ethnic minority patients with patients of Danish origin.

Of 1610 patients, 39.1% were ethnic minority patients. Ethnic minorities were younger, had longer symptom duration (7 vs 6 days, p < 0.001), and a higher risk of requiring high-flow oxygen upon admission (OR 1.41, 95% CI: 1.12;1.79) than patients of Danish origin until adjusted for age. However, ethnic minorities were not at higher risk of MV (HR 1.00, 95% CI: 0.69;1.44), 60-day mortality (HR 0.81, 95% CI: 0.61;1.09), long COVID (HR 0.82, 95% CI: 0.56;1.19) or related symptom diagnosis (HR 1.32, 95% CI: 0.85;2.05).

While ethnic minorities presented later and more severely ill at admission with a higher risk of receiving high-flow oxygen, their risk of MV, 60-day mortality, and long COVID were comparable to patients of Danish origin. This was largely explained by a substantial difference in age. Our findings emphasise the need for public health interventions to ensure equitable and timely healthcare access for all populations.