Researchers at Queen Mary University of London using UK Biobank data have suggested heart disease and vitamin D levels do not explain the increased risk of coronavirus in black, Asian and minority ethnic people.
Both had been suggested as potential explanations for the greater risk in some groups.
It did not look at deaths, rather who was testing positive for the virus in hospital.
Their study, published in the Journal of Public Health, showed weight, poverty and crowded homes all contributed to a higher chance of having the virus.
“Although some of the factors we studied appeared important, none of them adequately explained the ethnicity differences.”Researchers Dr Zahra Raisi-Estabragh and Prof Steffen Petersen
Even after taking them into account, people from ethnic minorities were still 59% more likely to test positive than those from white backgrounds and the reason remains unknown.
Dr Raisi-Estabragh and Prof Petersen added: “This is a really important question and one that we need to address urgently.
“There are a wide range of possible explanations including sociological, economic, occupational and other biological factors such as different genetic susceptibilities that need to be considered.”
Greater risk of severe COVID-19 in Black, Asian and Minority Ethnic populations is not explained by cardiometabolic, socioeconomic or behavioural factors, or by 25(OH)-vitamin D status: study of 1326 cases from the UK Biobank