Patients of Asian ethnicity have an increased risk of dying in hospital from Covid-19, while those of Black ethnicity have an increased risk of requiring hospital admission for the disease, warns a London study.
The findings, published in the journal EclinicalMedicine, suggest that different treatment strategies may be required for different ethnic groups.
"For Black patients, the issue may be how to prevent mild infection progressing to severe whereas for Asian patients it may be how to treat life-threatening complications," said one of the study authors Ajay Shah, Professor of Cardiology at King's College London and Consultant Cardiologist at King's College Hospital.
The study examined the relationship between ethnic background and SARS-CoV-2, the virus responsible for Covid-19.
The results confirm that minority ethnic patients bear a higher burden of the disease than White patients and also finds that Black patients and Asian patients are affected at different stages of the disease.
"The evidence is now clear that people from Black and minority ethnic groups are more severely affected by Covid-19," said Professor Chris Whitty, Chief Medical Officer for England and Head of the National Institute for Health Research (NIHR), Britain's largest funder of health and care research.
The study analysed data from 1,827 adult patients admitted to King's College Hospital, south-east London, with a primary diagnosis of Covid-19 between March 1 and June 2, 2020.
Researchers analysed mortality in this group, and also compared a subset of 872 admitted patients from inner south-east London with 3,488 matched controls residing in the same region to determine how ethnic background is associated with the need for hospitalisation for severe disease.
Of these 872 admitted patients, 48.1 per cent were Black, 33.7 per cent White, 12.6 per cent Mixed and 5.6 per cent were Asian ethnicity.
The analysis showed that Black and Mixed ethnicity patients have a three-fold higher risk of requiring hospital admission once infected with Covid-19 compared to White inner-city residents of the same region.
This is only partly explained by comorbidities and deprivation as adjusting for these factors Black patients still have a 2.2 to 2.7-fold higher admission risk.
However, in-hospital survival for these patients was not significantly different from White patients.
By contrast, Asian patients did not have a higher risk of requiring hospital admission with Covid-19 than White patients but their in-hospital death rate and need for intensive care unit admission was higher than the other groups.
The researchers observed that the minority ethnic patients were 10-15 years younger than White patients and had a higher prevalence of comorbidities, especially diabetes.
The study suggests that while comorbidities and socioeconomic factors contribute to the impact of Covid-19 on minority communities, there may be an important role for other factors such as biological factors which affect different subgroups in different ways.
The results of this study are likely to be applicable across the whole of London and similar UK cities, but more research is needed to translate to multi-ethnic populations in other countries.
The number of confirmed Covid-19 cases in Britain passed 5,90,800, while the total number of deaths reached 42,760 on Saturday.