Patients who are treated with steroids are more than twice as likely to develop diabetes compared to those who are not, a new study by researchers in Oxford has found.

Glucocorticoids, sometimes known as steroids, fight inflammation and are used to treat a wide range of inflammatory and autoimmune conditions, including asthma, rheumatoid arthritis, and cancers.

While they can be very effective in decreasing inflammation, glucocorticoids can also have a number of adverse effects, including increased blood sugar levels and diabetes.

This is more likely when people use glucocorticoid tablets or injections than when used as inhalers, creams, or drops.

The study, conducted by researchers at the University of Oxford's Radcliffe Department of Medicine's Diabetes Trial Unit, investigated how often patients being treated with glucocorticoids develop new-onset diabetes.

It found patients receiving systemic glucocorticoids were 2.6 times more likely to develop diabetes compared to those not receiving the treatment.

The study involved 451,606 adults admitted to Oxford University Hospitals NHS Foundation Trust, typically for less than a week, between January 1, 2013, and October 1, 2023.

None of the adults had diabetes at the start of the study, and none were taking systemic glucocorticoids.

Dr Rajna Golubic, who led the study, said: "Existing information on how much more common new diabetes is in patients treated with glucocorticoids is based on small studies including patients with one or a few conditions.

"We wanted to expand the data to get a more accurate idea of how likely it is that people could develop diabetes while being treated with these drugs."

She added: "These latest results give clinical staff a better estimate of how likely new diabetes is to occur and could prompt doctors to plan clinical care more effectively to detect and manage new diabetes.

"While we studied hospital patients, glucocorticoid tablets can be prescribed by GPs for conditions such as asthma and rheumatoid arthritis and it is important that they, too, are aware of the link.

"This study also shows how routinely collected clinical data can be used to help people with diabetes."

Around 17,258, or 3.8 per cent, of the patients were treated with systemic glucocorticoids, such as prednisolone, hydrocortisone, or dexamethasone while in hospital.

They were most commonly treated for autoimmune and inflammatory diseases and infections.

Of these patients, 316, or 1.8 per cent, developed diabetes while in hospital.

This compares with 3,430 of the 434,348 patients, 0.8 per cent, who did not receive systemic glucocorticoids.

The study was presented at the annual meeting of the European Association for the Study of Diabetes in Madrid.