Eosinophilic granulomatosis with polyangiitis (Churg‐Strauss): Clinical characteristics and long‐term followup of the 383 patients enrolled in the French Vasculitis Study Group cohort

OBJECTIVE: Earlier studies of eosinophilic granulomatosis with polyangiitis (Churg-Strauss) (EGPA), with limited patient numbers and followup durations, demonstrated that clinical presentation at diagnosis, but not outcome, differed according to antineutrophil cytoplasmic antibody (ANCA) status. This study was undertaken to describe the main characteristics of a larger patient cohort and their long-term outcomes. METHODS: A retrospective study of EGPA patients in the French Vasculitis Study Group cohort who satisfied the American College of Rheumatology criteria and/or Chapel Hill definitions was conducted. Patient characteristics and outcomes were compared according to ANCA status and year of diagnosis. RESULTS: We identified 383 patients diagnosed between 1957 and June 2009 (128 [33.4%] before 1997 or earlier) and followed up for a mean±SD of 66.8±62.5 months. At diagnosis, their mean±SD age was 50.3±15.7 years, and 91.1% had asthma (duration 9.3±10.8 years). Main manifestations included peripheral neuropathy (51.4%); ear, nose, and throat (ENT) signs (48.0%); skin lesions (39.7%); lung infiltrates (38.6%); and cardiomyopathy (16.4%). Among the 348 patients tested at diagnosis for ANCA, the 108 ANCA-positive patients (31.0%) had significantly more frequent ENT manifestations, peripheral neuropathy, and/or renal involvement, but less frequent cardiac manifestations, than the ANCA-negative patients. Vasculitis relapses occurred in 35.2% of the ANCA-positive versus 22.5% of the ANCA-negative patients (P=0.01), and 5.6% versus 12.5%, respectively, died (P<0.05). The 5-year relapse-free survival rate was 58.1% (95% confidence interval [95% CI] 45.6-68.6) for ANCA-positive and 67.8% (95% CI 59.8-74.5) for ANCA-negative patients (P=0.35). Multivariable analysis identified cardiomyopathy, older age, and diagnosis during or prior to 1996 as independent risk factors for death and lower eosinophil count at diagnosis as predictive of relapse. CONCLUSION: The characteristics and long-term outcomes of EGPA patients differ according to their ANCA status. Although EGPA relapses remain frequent, mortality has declined, at least since 1996.