Summary

Beta-thalassaemia is a congenital haemolytic anaemia characterized by partial (intermedia, TI) or complete (major, TM) deficiency in the production of β-globin chains.The primary aim of this study was to determine the prevalence of thromboembolic events in patients with β-thalassaemia.To achieve this,a multiplechoice questionnaire was sent to 56 tertiary referral centres in eight countries (Lebanon, Italy, Israel, Greece, Egypt, Jordan, Saudi Arabia and Iran), requesting specific information on patients who had experienced a thromboembolic event.The study demonstrated that thromboembolic events occurred in a clinically relevant proportion (1.65%) of 8,860 thalassaemia patients (TI – 24.7% or TM – 75.3%) from the Mediterranean and Iran. Thromboembolism occurred 4.38 times more frequently in TI thanTM (p<0.001), with more venous events occurring inTI and more arterial events occurring in TM.Thrombosis in thalassaemia was also more common in females, splenectomized patients and those with profound anaemia (haemoglobin <9 g/dl). Due to the increased risk of thromboembolic events, the rationale for splenectomy should perhaps be re-assessed and the role of transfusion therapy for the prophylaxis of thrombosis, among other complications, be evaluated prospectively.