Prediction of Relapse and Glucocorticoid Dependence in Eosinophilic Granulomatosis with Polyangiitis: Findings from a Large European Cohort

Eosinophilic granulomatosis with polyangiitis (EGPA) is a small vessel vasculitis characterized by eosinophilia, asthma, and ear, nose, throat (ENT) involvement. Although glucocorticoids (GCs) are effective in controlling symptoms, relapses and GC dependence are common. The aim of this study was to develop predictive models for vasculitis relapse and GC-dependent asthma and/or ENT symptoms. Methods: This multicenter European retrospective cohort study included EGPA patients fulfilling the 2022 ACR/EULAR criteria. Using the PMSAMPSIZE algorithm, we developed two multivariable prediction models: one for vasculitis relapse and another for GC-dependent asthma and/or ENT symptoms at 2 years. Internal validation was performed using bootstrapping. Results: A total of 809 patients were followed for a median of 72 months (interquartile range, IQR 37-115). Vasculitis relapse occurred in 228 patients with a 12-year cumulative incidence of 41.2% (95% CI 36.3-46.8). GC-dependent asthma and/or ENT symptoms were observed in 66.4% at 2 years. Predictors of vasculitis relapse included age (nonlinear), GC-dependent asthma before EGPA diagnosis (hazard ratio, HR 1.57), arthralgia (HR 1.27), myocarditis (HR 1.74), peripheral neuropathy (HR 1.39), MPO-ANCA (HR 1.56), and baseline eosinophil count (nonlinear). Predictors of GC-dependent asthma and/or ENT symptoms included older age (odds ratio, OR 0.98 per year), GC-dependent asthma at diagnosis (OR 1.50), chronic sinusitis (OR 1.78), and baseline eosinophil count (OR 0.70 per 109/L). Conclusion: Using a large EGPA cohort, we developed predictive models for vasculitis relapse and GC-dependent asthma and/or ENT symptoms. These tools may help guide treatment decisions. Prospective external validation in the current therapeutic era is warranted.