One explanation for why people from black and minority ethnic (BAME) backgrounds are dying in disproportionately high numbers is demography. The virus hit London first and hit it hardest. But even when you take these regional differences into account there is a mismatch. In particular, if you take into account that ethnic minorities are generally younger – particularly important for Covid-19 where 90% of deaths are in people over 60 – the ethnic differences become even more stark.
Co-morbidities could certainly play a role. The black population, where the discrepancy appears to be greatest, is particularly afflicted with hypertension. Diabetes is three-fold higher in this ethnic group. Both of those conditions will increase your risk of death once you’ve got Covid. The added problem is that these conditions occur at a younger age in people of black descent. However, in mitigation against that, certainly older people of black African descent don’t smoke as much, so have less respiratory disease, have lower rates of cancers and coronary disease. With Asian populations, the story is a bit different, but again there is a four-fold excess in diabetes and blood pressure rises higher with age in South Asians compared to Europeans.
Genetics sounds like an easy get-out clause, but it isn’t. Ethnicity is a complex socio-cultural construct, it’s not a biology construct. There’s no gene for being Asian. There’s no gene for being black. People of ethnic group membership can change over time and with age, it’s not an immutable thing and it very poorly maps on to any biology you can think of. People have looked to see if there’s a genetic explanation for these ethnic differences in chronic disease and have been unable to find one, despite having looked quite hard in large numbers. So there’s no evidence that genes explain the excess risk of Covid susceptibility. It’s important to put a nail in that one because it feels as if we can abdicate any responsibility for sorting this out and this really isn’t the case.
Ethnic minorities are over-represented in high-risk occupations, including health workers, in the transport sector and essential shop work. Clearly, there’s a huge amount of heterogeneity, but overall ethnic minorities are more likely to live in deprived, dense, over-crowded urban areas and are more likely to be disadvantaged. In some cases, household composition could play a role, particularly in Asian households where you have multi-generational households living together.
So both through occupation and residential reasons, they’re less able to socially isolate effectively and much more likely to be exposed to high doses of the virus. There’s some suggestion that the greater the dose you’re exposed to the more likely the disease is to prove fatal. That’s perhaps one reason why even quite young healthcare workers are succumbing to the disease.
The evidence on ethnic differences in healthcare seeking behaviour is quite messy, and we need to remember that these are quite heterogeneous groups. For instance, people of black ancestry have been found to be less likely to consult for chronic diseases like diabetes, but that doesn’t mean to say that if it’s an acute condition they won’t come forward. One study of people accessing antiviral flu treatments in the flu pandemic of 2009 found that ethnic minorities were less likely to ask and less likely to collect these. But whether this was due to reluctance, differences in access to healthcare, the way the message was put across or racism – it is difficult to pick apart because the healthcare seeking process is so complicated.
Ultimately, this is about health inequalities, about deprivation and affluence and how important socio-economic status is in determining health outcomes. This isn’t just an ethnicity story, it affects all of us. Britain has a long history of health inequalities. It’s critically important to understand and I’m relieved that the government is taking this seriously.
Prof Chaturvedi is director of the MRC Unit for Lifelong Health and Ageing at UCL