Exploring sex-specific differences in the presentation and outcomes of ANCA-associated vasculitis: a nationwide registry-based cohort study.

Objective: Sex-specific differences in the risk of end-stage renal disease (ESRD) in patients with anti-neutrophil cytoplasmic antibody-associated glomerulonephritis (ANCA-GN) stratified by histological classification have not been previously investigated.

Methods: Patients with biopsy-verified pauci-immune necrotizing GN and positive ANCA serology in the Norwegian Kidney Biopsy Registry between 1991 and 2012 were included. Patients with ESRD during follow-up were identified from the Norwegian Renal Registry. ESRD-free survival stratified by histological classifications was investigated.

Results: We analyzed 358 patients, of whom 87 progressed to ESRD during follow-up. Overall ESRD-free survival at 1 and 5 years in the entire cohort was 81 and 71% in males versus 90 and 80% in females, respectively; 94 and 84% in males versus 98 and 98% in females with focal histology, respectively; 85 and 76% in males versus 89 and 77% in females with mixed histology, respectively; 72 and 58% in males versus 90 and 78% in females with crescentic histology, respectively; and 52 and 46% in males versus 60 and 38% in females with sclerotic histology, respectively. Males had an increased risk of ESRD (adjusted hazard ratio, 2.44 [1.56-3.82]; p < 0.001).

Conclusions: Male sex is associated with increased risk of ESRD across all histological classes of ANCA-GN.