Explaining ethnic disparities in COVID-19 mortality: population-based, prospective cohort study

Ethnic disparities in COVID-19 hospitalizations and mortality have been reported but there is scant understanding of how these inequalities are embodied. The UK Biobank prospective cohort study comprises around half a million people who were aged 40-69 years at study induction between 2006 and 2010 when information on ethnic background and potential explanatory factors was captured. Study members were linked to a national mortality registry. In an analytical sample of 448,664 individuals (248,820 women), 354 deaths were ascribed to COVID-19 between 5th March and the end of follow-up on 17th September 2020. In age- and sex-adjusted analyses, relative to White participants, Black study members experienced around seven times the risk of COVID-19 mortality (odds ratio; 95% confidence interval: 7.25; 4.65, 11.33), while there was a doubling in the Asian group (1.98; 1.02, 3.84). Controlling for baseline comorbidities, socioeconomic circumstances, and lifestyle factors explained 53% of the differential in risk for Asian people (1.37; 0.68, 2.77) and 27% in Black study members (4.28; 2.67, 6.86). The residual risk in ethnic minority groups for COVID-19 deaths may be ascribed to unknown genetic factors or unmeasured phenotypes, most obviously racial discrimination.