Granulomatosis with polyangiitis: Study of 795 patients from the French Vasculitis Study Group registry.

Objective: To describe the characteristics and long-term outcomes of patients with granulomatosis with polyangiitis (GPA) from the French Vasculitis Study Group database.

Methods: Patients' clinical and laboratory characteristics, Birmingham Vasculitis Activity Score (BVAS)-assessed disease activity, malignancies, opportunistic infections, and vital status were collected at diagnosis and each visit. Estimated probabilities and predictors of overall (OS) and relapse-free survival (RFS) were analyzed by Cox regression.

Results: We enrolled 795 newly diagnosed patients, followed for a median of 3.5 years. Initial clinical manifestations involved ear, nose & throat (ENT; 80%), lungs (68%) and kidneys (56%). Among the 728 available ELISA results, 75.0% were PR3-ANCA-positive, 16.5% MPO-ANCA-positive and 62 (8.5%) ANCA-negative. Relapses occurred in 394 (50%) patients, involving ≥1 organ(s) affected at onset in 179 (46%), mainly ENT, lungs and kidneys, with mean BVAS 10.2 points below that at diagnosis (p<0.001). Five- and 10-year RFS rates were 37% and 17%, respectively. PR3-ANCA-positivity independently predicted relapse (p = 0.05) and prolonged survival (p = 0.038). OS-but not RFS-improved significantly over time (p<0.001); 10-year OS reached 88.2% (95% CI 83.9 to 92.7) for the 660 patients diagnosed after 2000. Infections were the main causes of death. Malignancy or opportunistic infection each occurred in ≤5% of the patients.

Conclusion: Survival has improved dramatically over the last decades but the high relapse rate remains a major concern for GPA patients, once again stressing the need for therapeutic strategy optimization to lower it. PR3-ANCA-positivity was associated with increased probability of relapse and survival.