Safety of glucocorticoid dose reduction in microscopic polyangiitis: a multicentre REVEAL cohort study.

Abstract

Objectives: This retrospective, multicentre study evaluated the safety of reducing glucocorticoids in patients with microscopic polyangiitis (MPA).

Methods: 223 newly diagnosed MPA patients, with treatment initiated between 2005 and 2023 in the REVEAL cohort, were divided by 6-month glucocorticoid dose (≤10 vs >10 mg/day prednisolone-equivalent). Baseline characteristics were balanced using overlap weighting based on age, sex, disease severity, disease activity, lung/kidney involvement, initial treatment, and year of treatment initiation. 10-year outcomes were assessed using Cox models, and predictors of glucocorticoid dose at 6 months were evaluated using logistic regression.

Results: Reducing glucocorticoids to ≤10 mg/day at 6 months did not show increased risks of all-cause mortality, infection-related mortality, infections requiring hospitalisation, all relapses, and major relapses. Treatment initiation ≥2020 was linked to glucocorticoid dose ≤10 mg/day at 6 months (odds ratio 5.54, 95% confidence interval 2.78-11.43). Sensitivity analysis (12 mg/day threshold) showed similar results.

Conclusions: Reducing glucocorticoids to ≤10 mg/day at 6 months was not linked to increased mortality, infection, or relapse, suggesting it may be a feasible intermediate target. However, more aggressive glucocorticoid reduction per guidelines might be needed for further infection risk reduction. Individualised tapering with close monitoring remains crucial.