Efficacy of High Dose Vitamin D on Pulmonary Artery Pressure in Thalassemia Patients Undergoing Blood Transfusion: A Randomized Trial

Pulmonary arterial hypertension (PAH) may result in cardiomyopathy which is a major cause of death in thalassemia patients. Vitamin D is associated with benefits in cardiovascular disorders. Our purpose was to study effects of vitamin D on pulmonary artery pressure in thalassemia major and intermedia patients.

This randomized trial was performed on 26 patients with thalassemia major (TM) and intermedia (TI) in Amir-Kabir Hospital, Arak, Iran in 2019-2020. Patients were randomized 1:1 to intervention group (vitamin D 50,000 IU/week) and control group (received no supplement) for 20 weeks. Echocardiography was used to measure pulmonary artery pressure and assess cardiovascular function. The levels of 1,25-dihydroxyvitamin D3, ferritin, and cardiac iron content were measured in study groups.

After 20 weeks, pulmonary arterial pressure (PAP), tricuspid regurgitant velocity (TRV), and pulmonary regurgitant velocity (PRV) significantly improved in the intervention group compared to the control group (P= 0.010, P= 0.003, and P= 0.001, respectively). Moreover, ejection fraction (EF) had significant increase in the intervention group compared to the control group (P= 0.008), although vitamin D supplementation had no significant impact on cardiac T2* values (P= 0.827), systolic and diastolic blood pressure (P= 0.388 and P= 0.509, respectively) and serum hemoglobin and ferritin levels (P= 0.557 and P= 0.620) as compared to the control group. However, the levels of 25-OHD3 significantly increased in the intervention group compared to the control group (P= 0.036).

This study showed that vitamin D 50000 IU/week can improve PAP in patients with thalassemia. Sufficient intake of vitamin D may prevent cardiomyopathies related to PAH.