Early Vascular Alterations in Acromegaly

Acromegaly is associated with increased cardiovascular mortality; however, little is known about the early atherosclerotic changes occurring in such patients. Endothelial function, in the form of flow-mediated dilation (FMD) of the brachial artery, and intima-media thickness (IMT) of the carotid artery were measured by B-Mode ultrasound in: 1) 18 patients with active acromegaly; 2) 12 subjects cured from acromegaly; 3) 18 subjects without acromegaly, each of them matched to an acromegalic patients for age, sex, risk factors and treatments; and 4) 10 healthy subjects. Results are expressed as median plus (25th, 75th) percentile. In active acromegalic patients, FMD was 5.7 (3.9, 7.7)%, significantly lower than in both healthy subjects (P < 0.01) and matched controls (P < 0.01). No difference between groups was observed for endothelium-independent vasodilation. Acromegalic patients had also higher IMT than healthy controls (P < 0.05), whereas no difference was observed with matched controls. In cured acromegalic patients, FMD was 9.2 (7.7, 10.5)%, significantly lower (P < 0.01) than in healthy controls but higher (P < 0.01) than in active patients. No difference in IMT was observed between active and cured patients. In conclusion, patients with acromegaly have functional and morphological vascular alteration that seems, at least in part, dependent on the GH excess itself.