Baseline Hemoglobin Values and Clinical Outcomes in Acute Venous Thromboembolism: Insights From the RIETE Registry

Venous thromboembolism (VTE) is a major global health concern and a leading cause of morbidity and mortality. While anticoagulation effectively reduces the risk of recurrent VTE, it is associated with an inherent risk of bleeding. Identifying patient characteristics that influence these risks is critical for personalized management. Baseline hemoglobin (Hb) values have emerged as a potential prognostic marker [1-5], reflecting both underlying comorbidities and hemostatic alterations. However, the impact of Hb values on both thrombotic and bleeding complications in anticoagulated VTE patients remains insufficiently characterized. We analyzed data from 111,646 patients with acute VTE included in the RIETE registry, a large multinational prospective cohort (ClinicalTrials.gov identifier: NCT02832245) [6]. Patients were stratified into Hb quintiles: < 11.4, 11.4–12.6, 12.7–13.6 (reference), 13.7–14.7, and > 14.7 g/dL. We assessed 90-day rates of recurrent VTE, major bleeding, arterial ischemic events (myocardial infarction, ischemic stroke, or limb amputation), and all-cause mortality. Multivariable logistic regression models were adjusted for demographic and clinical characteristics, including VTE risk factors, initial VTE presentation, comorbidities, renal function, leukocyte and platelet counts, anticoagulant strategy, and concomitant medications.