Impact of gender on baseline presentation and outcome in adult IgA vasculitis.

Objectives: Adult IgA vasculitis (IgAV) is more common in males, but the potential impact of gender remains unclear. We aimed to describe the impact of gender on presentation and outcome in adult IgAV.

Methods: We retrospectively analysed data from a multicentre retrospective cohort of 260 patients (IGAVAS). Comparisons were made according to gender status.

Results: Data from 259 patients (95 females and 164 males) were analysed. Compared with females, baseline presentation in males was similar for cutaneous involvement (100% vs 100%, P = 1.0), joint involvement (60% vs 63%, P = 0.7), gastrointestinal involvement (57% vs 45%, P = 0.093) and glomerulonephritis (73% vs 64%, P = 0.16). Glomerulonephritis was more severe at baseline in males than in females, with a lower median estimated glomerular filtration rate (eGFR) [90 (IQR 59-105) vs 97 ml/min/1.73 m2 (76-116), P = 0.015] and increased median proteinuria (0.84 vs 0.58 g/day, P = 0.01). There were no differences in histological findings in patients who had a kidney biopsy. Methylprednisolone was more frequently used in males (40% vs22%, P = 0.015), as were immunosuppressants, especially cyclophosphamide (24% vs 6%, P = 0.0025) and azathioprine (10% vs 2%, P = 0.038). Analysis of treatment response showed that males had more frequent refractory disease (30% vs 13%, P = 0.004). Long-term outcomes (mortality and progression to chronic kidney failure) did not differ.

Conclusion: Kidney involvement in IgAV appears to be more severe in males, which is supported by more intensive treatment contrasting with a lower response rate. This study raises the question of gender as a new prognostic factor in adult IgAV.