Recurrence rate of venous thromboembolic events in granulomatosis with polyangiitis

OBJECTIVE: The incidence of first-time venous thromboembolic events (VTEs) is high in granulomatosis with polyangiitis (GPA). The incidence of recurrent VTEs is unknown. We aimed to describe the recurrence rate of second VTEs in patients with GPA. METHODS: Retrospective chart review was performed in patients with GPA and at least one VTE at a single centre from 2002 to 2016. Inclusion criteria were 1990 ACR criteria or 2012 Revised International Chapel Hill nomenclature for GPA, at least two follow-up visits, at least one VTE during the study period, and VTE occurrence after or within 3 months before GPA diagnosis. Second VTE event-free survival rates were estimated. RESULTS: Out of 147 patients initially screened for GPA and with at least one VTE, 84 met inclusion criteria. Median age at first VTE was 57 years. Incidence rate for second VTE was 8.4 events per 100 patient-years (95% CI: 5.7, 12.3). Eighty-three point three per cent of first VTEs and 57.7% of second VTEs occurred when disease was active (P < 0.001). Renal involvement and constitutional symptoms at the time of first VTE were associated with VTE recurrence. CONCLUSION: GPA has a high rate of VTE recurrence compared with the reported data in the general population with unprovoked VTE. Our results suggest that VTE in GPA is a recurrent co-morbidity, not always during active vasculitis, and more so in those with renal involvement and constitutional symptoms at the time of first VTE.