VTE outcomes in hemoglobinopathy patients: A propensity-matched analysis. insights from the riete registry.

Abstract Introduction: Patients with hemoglobinopathies, such as sickle-cell disease and thalassemia, are associated with higher rates of venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism. However, there are currently no data on the risk of VTE recurrence in patients with hemoglobinopathies compared with those without hemoglobinopathies who have already experienced a VTE event. Methods: Data from patients with a VTE event enrolled in the Computerized Registry of Patients with Venous Thromboembolism (RIETE) between January 1, 2001, and June 16, 2025, were extracted. Patients were stratified based on the presence of any hemoglobinopathy. The primary endpoint was 2-year net adverse clinical events (NACE), defined as the composite of all-cause death, VTE recurrence, and any bleeding. Secondary endpoints included the individual components of the primary endpoint and major bleeding. Bleeding events were classified according to the criteria of the International Society on Thrombosis and Haemostasis (ISTH). Clinical outcomes were compared between groups after propensity score matching in a 1:2 ratio to account for baseline differences in age, sex, weight, inpatient evaluation at diagnosis, intensive care unit admission, and use of antiplatelet therapy. Cox regression models were used to calculate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). Results: From the original sample of 132,679 patients with a VTE event, 309 patients were diagnosed with a hemoglobinopathy. Baseline characteristics were generally similar between groups, although patients with hemoglobinopathies were younger (60.0 [40.0–73.0] vs. 68.0 [54.0–78.0] years). After propensity score matching, 927 patients were included in the analysis, of whom 618 were classified as non-hemoglobinopathy. At 2 years, no significant difference in NACE was observed between groups (54.3% vs. 50.3%; HR 1.04, 95% CI 0.74–1.47, p=0.809). Similarly, there were no significant differences in all-cause mortality (23.2% vs. 26.1%; HR 0.64, 95% CI 0.39–1.05, p=0.078) or VTE recurrence (34.2% vs. 21.6%; HR 1.40, 95% CI 0.80–2.45, p=0.235). Patients with hemoglobinopathies experienced higher rates of any bleeding (24.0% vs. 10.6%; HR 2.52, 95% CI 1.51–4.21, p<0.001) and major bleeding (10.0% vs. 3.5%; HR 2.85, 95% CI 1.38–5.86, p=0.005) compared with those without hemoglobinopathies. Conclusions: Among patients presenting with VTE, those with hemoglobinopathies appear to be younger and have a higher incidence of 2-year bleeding, including major bleeding, without significant differences in NACE, VTE recurrence, or all-cause mortality compared to those without hemoglobinopathies.