People with type 2 diabetes mellitus (T2DM) who are taking renin-angiotensin system (RAS) blockers may be reducing their risk of hospitalisation for a severe lower respiratory tract infection, Australian researchers say.

The findings, based on data from the Fremantle Diabetes Study, showed that patients on RAS blockers had a 36% reduction in the risk of hospitalisation for influenza or pneumonia compared with others not on the drugs, over a mean follow-up of 6.4 years.

Although the study did not directly address COVID-19, the findings provide “some support” for keeping patients with T2DM at risk of COVID-19 or with mild infection on their RAS blockers, providing there is not a risk of acute kidney injury, the authors write.

Data for 1482 people in the cohort with confirmed T2DM (mean age 66 years, 52% male) were analysed to ascertain the risk of hospitalisation for influenza or pneumonia, report endocrinologist Professor Timothy Davis and epidemiologist Associate Professor Wendy Davis, from the University of Western Australia.