RA patients on low-dose glucocorticoids at greater risk of serious infection

Long-term use of low-dose glucocorticoids results in a dose-dependent increase in the risk of serious infection in patients with rheumatoid arthritis (RA) on stable disease-modifying antirheumatic drug (DMARD) regimen, with small but significant risk even at doses of ≤5 mg/day, a study has shown.

“Clinicians should balance the benefits of low-dose glucocorticoids with this potential risk,” according to the authors.

This retrospective cohort study identified adults with RA receiving a stable DMARD therapy for >6 months using Medicare claims data and Optum’s deidentified Clinformatics Data Mart database from 2006 to 2015.

Inverse probability–weighted analyses, with 1-year cumulative incidence predicted from weighted models, were performed to examine the associations between glucocorticoid dose (none, ≤5, >5 to 10, and >10 mg/d) and hospitalized infection.

Overall, 247,297 observations have been identified from 172,041 Medicare patients and 58,279 observations among 44,118 patients in Optum. Glucocorticoids were given to 47.1 percent of Medicare patients and 39.5 percent of Optum patients after 6 months of stable DMARD use.

The 1-year cumulative incidence of hospitalized infection in Medicare patients not on glucocorticoids was 8.6 percent compared with 11.0 percent (95 percent confidence interval [CI], 10.6–11.5) for glucocorticoid dose of ≤5 mg/day, 14.4 percent (95 percent CI, 13.8–15.1) for >5 to 10 mg/day, and 17.7 percent (95 percent CI, 16.5–19.1) for >10 mg/day (p<0.001 for all vs no glucocorticoids).

In Optum patients not receiving glucocorticoids, the 1-year cumulative incidence of hospitalized infection was 4.0 percent relative to 5.2 percent (95 percent CI, 4.7–5.8) for glucocorticoid dose of ≤5 mg/day, 8.1 percent (95 percent CI, 7.0–9.3) for >5 to 10 mg/day, and 10.6 percent (95 percent CI, 8.5–13.2) for >10 mg/day (p<0.001 for all vs no glucocorticoids).

This study was limited by potential residual confounding and misclassification of glucocorticoid dose.