A large British study has confirmed the increased risk of infections when inflammatory diseases are treated long-term with glucocorticoids, beginning with the lowest doses and rising sharply from there.
A team from the University of Leeds looked at the records of nearly 40,000 patients with polymyalgia rheumatica or giant cell arteritis or both, and found more than half (56%) had at least one infection during a median follow-up of just under five years. Of those, 27% required hospital admission and 7% died within a week of diagnosis.
The cumulative risk of all-cause infection – bacterial, viral, parasitic or fungal – over 10 years was 79%. The most common infections were lower respiratory tract, conjunctivitis and shingles.
The study, published in the Canadian Medical Association Journal, found strong dose-response relationships starting at low doses.
After one year, infection risk had increased from a glucocorticoid-free baseline of 12.9% to 18% for doses under 5mg of prednisolone per day and to 36% for 25mg per day or more.
The dose-response associations held across sex, disease duration and infection type.
The findings “highlight the need for regular review of glucocorticoid requirements, even at low doses”, the authors wrote.
“Patients and clinicians should be educated about the risk of infection, need for symptom identification, prompt treatment, timely vaccination and documentation of history of chronic infection (e.g. herpes zoster).”
They say the dose-response estimates can now be used in benefit-harm evaluations and cost-effectiveness studies of glucocorticoid-sparing drugs.