Dementia and other cognitive disorders are likely to be risk factors for developing severe COVID-19, according to research from the University of Georgia.
The findings highlight the need for special care for populations with these pre-existing conditions during the pandemic.
The study was published online in the journal Brain, Behavior and Immunity.
In the study, the researchers analysed data from nearly 1,000 diseases and two specific genes to compare the health profiles of COVID-19 patients with those testing negative, looking for commonalities in COVID-19 patients.
The study relied on data from UK Biobank, a long-term study of more than 500,000 participants investigating the respective contributions of genetic predisposition and environmental exposure to the development of the disease.
Beginning in March, the UK Biobank started to report the COVID-19 status of its participants.
The team in the Franklin College of Arts and Sciences department of genetics, led by assistant professor Kaixiong Ye and his postdoc, Jingqi Zhou, promptly connected the COVID-19 status to the electronic health data.
"We took a hypothesis-free approach and the most statistically significant ones are the cognitive disorders and Type 2 diabetes," said Ye, the senior author of the study.
"Right now, we do no know the mechanisms behind these associations, we only know these are more common in COVID-19 patients." Analysing the genetic factors that make some individuals at higher risk for severe COVID-19, the team focused on two genes: ACE2 and TPMPRSS2, known to be critical for the virus to enter into human cells.
"In the TMPRSS2 gene we found that a specific genetic variation is more common in the COVID-19 patient," he said.
The research team also found that variations in genes related to SARS-CoV-2 infection may be associated with severe COVID-19 that requires hospitalisation.