Association of clonal haematopoiesis with recurrent venous thromboembolism: A case-control study.

Venous thromboembolism (VTE) is the third most common cardiovascular disease. Clonal haematopoiesis (CH) is linked to cardiovascular disease risk, but its potential association with VTE remains poorly understood. We assessed the prevalence of CH in patients with recurrent VTE (n = 107; median age [IQR] 57 [48-63] years, 44.9% female) and matched healthy controls (n = 127; median age [IQR] 53 [45-60] years, 51.2% female) to investigate a putative association of CH with VTE risk. We detected 12 CH-associated mutations in 11 (10.3%) VTE cases and six mutations in 5 (3.9%) controls. Thus, patients with recurrent VTE tended to have higher odds of presenting with CH compared to controls (OR: 2.74, 95% CI: 0.95-9.16). Moreover, the odds of detecting CH were significantly higher in VTE cases in the subgroup of individuals without thrombophilia (OR: 4.58, 95% CI: 1.48-15.99). VTE cases with CH showed elevated platelet counts compared to cases and controls without CH (median [IQR]: 292 [254-298], 223 [198-260] and 220 [185-259] × 10⁹/L; both p < 0.01). Fibrinogen, sP-selectin, D-dimer and hsCRP levels did not differ according to CH status. Overall, we identified a trend for an association between CH and recurrent VTE, particularly in individuals without underlying thrombophilia, warranting further research in this patient group.