Objective: To determine the frequency and risk factors of venous thromboembolic events (VTE) in Wegener’s granulomatosis (WG), microscopic polyangiitis (MPA), and so far unstudied Churg–Strauss syndrome (CSS) and polyarteritis nodosa (PAN).
Methods: Retrospective, systematic analysis and comparison between VTE and non-VTE patients’ characteristics among the 1130 WG, MPA, CSS or PAN patients included in the French Vasculitis Study Group cohort.
Results: During a mean follow-up of 58.4 ± 45.8 months, 83 VTE occurred in 74 (6.5%) patients, with a median vasculitis–VTE-diagnosis interval of 5.8 months [–3 to +156]. VTE occurred in 7/285 (2.5%) PAN, 19/232 (8.2%) CSS, 30/377 (8%) WG, and 18/236 (7.6%) MPA patients. Multivariate analysis retained age, male sex or prior VTE or stroke with motor deficit as being associated with a higher VTE risk. The adjusted odds ratio [95% confidence interval] for VTE was 2.88 [1.27–6.50] for WG, MPA and CSS patients compared to PAN (p= 0.01).
Conclusion: Our results suggest that, like WG and MPA, CSS patients are at greater risk of VTE, than those with PAN. The reasons for this difference remain to be elucidated.