Background/Purpose: ANCA-associated vasculitis (AAV) has been associated with an increased risk of venous thromboembolic events (VTE). However, limited data are available regarding the precise timing, nature, severity, management, and recurrence of VTE in this population. This study aimed to characterize the clinical features of VTE in AAV patients and assess the impact of immunosuppressive and antithrombotic therapy on outcomes.

Methods: We conducted a retrospective monocentric cohort study including patients diagnosed with AAV according to the 2022 ACR/EULAR classification criteria who experienced at least one VTE. VTE types, timing in relation to AAV diagnosis and disease activity, therapeutic strategies (including anticoagulation duration and immunosuppression), and VTE-related outcomes were recorded. Recurrence rates and their association with vasculitis flares were also analyzed.

Results: Among 34 patients with AAV and VTE, 28 (82%) had granulomatosis with polyangiitis, 2 (6%) microscopic polyangiitis, and 4 (12%) eosinophilic granulomatosis with polyangiitis. The most common VTEs were pulmonary embolism (n=21, 62%), deep vein thrombosis (n=20, 59%), with 9 patients (26%) experiencing both, and deep vein thrombosis of atypical sites (n=2, 6%). VTE occurred within the first 6 months of AAV diagnosis in 16 cases (47%), or following a vasculitis flare in 9 patients (26%). In these patients, the median time from diagnosis of vasculitis to VTE was 30 days (IQR 11–96). In the remaining 9 patients, VTE occurred at a median of 69 days (IQR 50–82) after AAV flare. Median Birmingham Vasculitis Activity Score (BVAS) at VTE onset was 5.5 [IQR 0–15]. At the time of VTE, 88% of patients (n=30) were under immunosuppressive treatment and 29 were receiving systemic glucocorticoids with a median prednisone dose of 32.5 mg/day (IQR 9–60). Anticoagulation therapy was administered for a median duration of 6 months [IQR 3–8.25]; 43% received < 6 months, 43% between 6–12 months, and 14% >12 months. Recurrent VTE occurred in 6 patients (19%) after anticoagulant discontinuation, of whom 3 experienced recurrence concomitant with vasculitis relapse. Two patients (6%) died as a direct consequence of thromboembolic complications.

Conclusion: VTEs in AAV patients frequently occur during periods of active disease and predominantly manifest as pulmonary embolism or deep vein thrombosis. Despite immunosuppressive treatment, thrombotic events still occur. Recurrence was observed in 20% of patients, particularly during relapse. These findings underscore the importance of considering VTE when clinically suspected, especially during AAV onset or relapse.

« Back to ACR Convergence 2025

ACR Meeting Abstracts - https://acrabstracts.org/abstract/timing-management-and-outcomes-of-venous-thromboembolic-events-in-anca-associated-vasculitis-a-retrospective-cohort-study/