Objective: We examined endothelial function and serum levels of inflammatory mediators in transfusion-dependent patients with beta-thalassemia major (BTM).

Methods: The study population consisted of 85 patients with BTM (aged 25±0.6) with normal left ventricular function and 71 healthy age- and sex-matched controls. Forearm blood flow was measured with gauge-strain plethysmography. Forearm vasodilatory response to reactive hyperemia (RH%) or to nitrate (NTG%) were assessed. Serum levels of interleukin 6 (IL-6), soluble vascular cell adhesion molecule (sVCAM-1) and soluble intercellular adhesion molecule (sICAM-1) were determined with ELISA.

Results: Patients had significantly lower levels of total cholesterol (124±4.5 vs. 208±7mg/ml, p < 0.01), ApoA1 (122±3 vs. 129±4mg/ml, p < 0.05), ApoB (62±3 vs. 97±4mg/ml, p < 0.01) and Lp(a) (8.1±1.4 vs. 15.5±4mg/ml, p < 0.01) than controls. IL-6 levels were significantly higher in patients (3.1±0.31 pg/ml) than controls (1.14±0.16 pg/ml, p < 0.01). Similarly, sVCAM-1 and sICAM-1 levels were significantly higher in patients (515±30 and 362±24 ng/ml, respectively) than controls (331±12.6 and 268±13.05 ng/ml, respectively, p < 0.01 for both). Maximum hyperemic forearm blood flow and RH% were lower in patients (7±0.4 ml/100 ml tissue/min and 48±2.5%, respectively) than controls (8.6±0.2 ml/100 ml tissue/min and 88.5±5.4%, respectively, p < 0.01 for both).

Conclusions: BTM is associated with impaired endothelial function and increased levels of IL-6, sVCAM-1 and sICAM-1, suggesting a potential role of inflammation and endothelial dysfunction in the cardiovascular complications of the disease. These observations concerned subjects with normal left ventricular ejection fraction, which implies an early implication of these mechanisms in the pathophysiology of heart insult in BTM.