A faulty gene linked to dementia doubles the risk of developing severe COVID-19, according to new research.
Using data from the UK Biobank, scientists from the universities of Exeter and Connecticut found a high risk of coronavirus among people of European ancestry who carry two faulty copies of the APOE gene.
One in 36 Biobank participants of that background has those mutations, which increase the risk of Alzheimer’s by up to 14 times.
They also raise the chance of developing heart disease, compared to people with the non-faulty gene.
Scientists from both universities’ medical schools say the risk of getting a severe form of COVID-19 is doubled by the presence of the copies, even if a patient has neither Alzheimer’s nor heart disease.
During their research, they found that 2.36% of UK Biobank participants with European ancestries had the faulty gene.
Among those who tested positive for COVID-19, the figure more than doubled, rising to 5.13%.
It is hoped that discovering why that is the case will lead to new ideas for treatments.
The same team has previously discovered that people with dementia are three times more likely to get severe COVID-19 – possibly because of the high prevalence of the virus in care homes.
“This is an exciting result because we might now be able to pinpoint how this faulty gene causes vulnerability to COVID-19,” said Dr Chia-Ling Kuo from the University of Connecticut School of Medicine.
“It’s also important because it shows again that increasing disease risks that appear inevitable with ageing might actually be due to specific biological differences, which could help us understand why some people stay active to age 100 and beyond, while others become disabled and die in their sixties.”
Professor David Melzer, who led the team, said: “Several studies have now shown that people with dementia are at high risk of developing severe COVID-19.
“This study suggests that this high risk may not simply be due to the effects of dementia, advancing age or frailty, or exposure to the virus in care homes.”
“The effect could be partly due to this underlying genetic change, which puts them at risk for both COVID-19 and dementia.”
The researchers analysed data from the UK Biobank, which collects health and genetic data on 500,000 people.
The study is published in the Journal of Gerontology: Medical Sciences.