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 stomach and intestine illnesses.
Observational studies report a link between GORD and greater COVID-19 risk, which could be explained by the fact both share risk factors like:
However, QIMR Berghofer researcher Dr Jue-Sheng Ong said the study suggests there could be a more direct causal relationship between acid reflux and COVID-19 experience.
“By analysing large-scale genetic data 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 link.
Our analysis found obesity explained part of the relationship between acid reflux and COVID-19 risk. It didn’t explain all of it,” he said.
“These findings suggest GORD could play a direct causal role in increasing the risk of severe COVID-19 and COVID-19 hospitalisation,” Dr Ong said.
“It isn’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,” he said.
Further studies are necessary to validate the results, and explore the biological mechanisms linking risk factors like obesity, acid reflux and COVID-19.
The QIMR Berghofer study was published in 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. The project was funded by grants from the National Health and Medical Research Council of Australia.