Optimal glucocorticoid tapering in anti-synthetase syndrome-associated interstitial lung disease: A multicentre MYKO cohort study

Abstract Objectives To explore glucocorticoid (GC) tapering target in patients with acute/subacute anti-synthetase syndrome–associated interstitial lung disease (ASyS-ILD). Methods We retrospectively analysed 86 patients with newly diagnosed acute/subacute ASyS-ILD from the MYKO cohort. Patients were grouped using prednisolone-equivalent dose thresholds of 15, 12.5, and 10 mg/day at 6 months. Exploratory three-group analyses categorised patients into ≤12.5, 12.5–15, and >15 mg/day. Matching weights adjusted for baseline confounders. Cox proportional-hazards models evaluated 5-year all-cause mortality and event-free survival for disease flares and infections requiring hospitalisation. A multivariable logistic regression assessed factors associated with achieving ≤15 mg/day at 6 months. Results In two-group analyses, the ≤15 mg/day group had a lower infection risk (hazard ratio (HR) 0.18, 95% confidence interval (CI) 0.04–0.81), whereas analyses using other thresholds showed no clear differences. In the three-group analyses, patients receiving 12.5–15 mg/day tended to have the lowest flare risk. Female sex was associated with achieving ≤15 mg/day at 6 months (odds ratio 3.29, 95% CI 1.09–10.13). Conclusions Tapering to a prednisolone-equivalent dose of 12.5–15 mg/day at 6 months may represent a reasonable target to balance risks of flares and infections in patients with acute/subacute ASyS-ILD.