In the largest study to date on the risk factors associated with COVID-19, researchers have found that people of Asian and Black ethnic backgrounds are at a higher risk of death from the virus, but were still unable to fully explain why.
The study, carried out by academics at the University of Oxford and the London School of Hygiene and Tropical Medicine (LSHTM), analysed National Health Service data from 17.4 million UK adults between early February and the end of April.
This makes it the largest study on COVID-19 conducted by any country to date, and it offers the strongest evidence currently available on risk factors associated with COVID-19.
Notable findings from the study include the fact that people of Asian and Black ethnic backgrounds were found to be at higher risk of death than white people.
Commentators and researchers have previously speculated that this may be due to a higher prevalence of medical problems such as cardiovascular disease or diabetes, or socio-economic factors such as high rates of deprivation among black and ethnic minority (BAME) communities.
However, the study concluded that this higher risk was only partially attributable to pre-existing clinical risk factors or deprivation.
Consequently, researchers are calling for further work to be conducted in order to fully understand why BAME people are at such an increased risk of death.
Additionally, people from deprived social backgrounds were also found to be at a higher risk of death, which also could not be explained by other risk factors.
Other key factors found to be most heavily associated with COVID-19 death included being male, older in age, or suffering uncontrolled diabetes and severe asthma.
Professor Liam Smeeth, professor of clinical epidemiology at LSHTM and co-lead on the study, said that highly accurate data on which patients are most at risk is needed in order to manage the pandemic and improve patient care.
“The answers provided by this OpenSAFELY analysis are of crucial importance to countries around the world. For example, it is very concerning to see that the higher risks faced by people from BAME backgrounds are not attributable to identifiable underlying health conditions.”
Dr Ben Goldacre, director of the DataLab in the Nuffield Department of Primary Care Health Sciences at the University of Oxford and also co-lead on the study, said that during a global health emergency “we need answers quickly and accurately,” which means very large and current datasets are needed.
“The UK has phenomenal coverage and quality of data. We owe it to patients to keep their data secure; and we owe it to the global community to make good use of this data. That’s why we have developed a new highly secure model, taking the analytics to where the data already resides.”
The study linked data about patients that had been hospitalised with COVID-19 with data held in primary care records processed by TPP.
This was carried via the ‘OpenSAFELY’ analytics platform, a new secure mechanism that allowed health records to be linked where they are stored for individual care.
This is designed to minimise the security risks associated with transferring and storing data elsewhere, to deliver analyses quickly and safely while preserving patient privacy. The data is pseudonymised before it can be accessed by researchers.
Further analyses using OpenSAFELY are currently underway, including investigations into the effects of specific drugs routinely prescribed in primary care.
[Edited by Zoran Radosavljevic and Benjamin Fox]