Arthritis medication increases type 2 diabetes risk, researchers suggest

A drug that is commonly prescribed to treat rheumatoid arthritis could increase the risk of patients developing type 2 diabetes, a study finds.
Glucocorticoid therapy – a type of steroids – is used to control the inflammation that is caused by rheumatoid arthritis. But when the dosage of the drug is higher, University of Manchester researchers found that the risk of type 2 diabetes is too.
The Manchester study team examined records of more than 20,000 patients with rheumatoid arthritis in the UK, and 12,600 American patients. They then compared rates of new-onset diabetes in patients who were prescribed glucocorticoids to those who were not.
During a 5.4 year follow-up for British patients, 10 per cent were diagnosed with diabetes; and during a 3.4 year follow-up for American patients, 6.8 per cent developed type 2 diabetes. However, the risk was only affected by the dose in the most recent six months.
Each 5mg increase per day of a glucocorticoid called prednisolone was associated with a 25-30 per cent increase in diabetes risk. But a dose of less than 5mg was not associated with any measurable diabetes risk compared to no treatment.
Senior author Dr Will Dixo, director of the Arthritis Research UK Centre for Epidemiology at the University of Manchester, said: “Doctors treating people with arthritis have to make a decision how best to prescribe glucocorticoids by balancing the benefits against the risks. However, until now, no studies have considered how the risk changes with the dose and duration of treatment.
“This research provides important evidence for doctors to make this decision [and] shows that low doses of steroids (below 5mg/day) do not increase the risk of diabetes. However, there is an increased risk of acquiring diabetes for people who use them for long periods or at high doses which can now be quantified.”
Dixon warned, however, that people should not stop using glucocorticoids because they are effective in treating flare-ups in joint pain, and can help people with rheumatoid arthritis who do not respond to other treatments.
The findings appear in the journal Arthritis and Rheumatology.