New research from QIMR Berghofer Medical Research Institute has found that people who are genetically predisposed to develop acid reflux may be more vulnerable to COVID-19.
The research found that genes predicted to cause gastro-oesophageal reflux disease (GORD) were associated with an increased risk of severe COVID-19 and COVID-19 hospitalisation.
GORD is a chronic form of acid reflux and one of Australia’s most common gastrointestinal conditions.
Observational studies have reported an association between GORD and increased COVID-19 risk, which could be explained by the fact both conditions share common risk factors like obesity, hypertension, cardiovascular disease and diabetes.
However, QIMR Berghofer researcher Dr Jue-Sheng Ong said their study suggested there could be a more direct causal relationship between acid reflux and COVID-19 outcomes.
“By analysing large-scale genetic data on GORD and COVID-19 susceptibility, we found that genes predicted to cause GORD were linked with a 15 per cent increase in the risk of severe COVID-19 and hospitalisation,” Dr Ong said.
“We then used statistical modelling to test whether common risk factors could be driving the association. Our analysis ultimately found that obesity explained part of the relationship between GORD and COVID-19 risk, but it didn’t explain all of it.
“These findings suggest GORD could potentially play a direct causal role in increasing the risk of COVID-19 hospitalisation.”
The study involved analyses of genetic data from the UK Biobank, QIMR Berghofer’s QSkin study and The COVID-19 Host Genetics Initiative.
It was made possible by previous QIMR Berghofer research published in the journal Gut earlier this year, which identified 60 new genes linked to acid reflux.
“We’ve now found 88 genes or genetic markers that are associated with whether or not a person gets acid reflux,” Dr Ong said.
“That allowed us to take this next step, where we could analyse those 88 genetic markers against genetic information from the COVID-19 Host Genetics Initiative, which includes data on people who get COVID-19, develop severe COVID-19 symptoms or are hospitalised for COVID-19.”
Dr Ong said it wasn’t clear whether the increased risk of severe COVID-19 and hospitalisation relates to GORD itself, or to treatments people take when they’re diagnosed with GORD.
Further studies are warranted to validate the results, and explore the biological mechanisms linking risk factors like obesity, acid reflux and COVID-19.
The QIMR Berghofer study has been published by the journal Human Molecular Genetics. It was led by Professor Stuart MacGregor, head of the Institute’s Statistical Genetics Laboratory.
QSkin, which along with UK Biobank and the COVID-19 Host Genetics Initiative provided genetic data used in the study, was funded by grants from the National Health and Medical Research Council of Australia.