Early Vascular Alterations in Acromegaly

Abstract

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.

Aortic intima-media thickness and lipid profile in macrosomic newborns

“…A positive association between carotid intima-media thickness (cIMT) and high IGF-I levels has also been observed in acromegalic patients [7]. It has not yet been clarified how the excess of GH/IGF-I induces IMT thickening, but the process could partly be attributed to the direct effects of IGF-I on vascular smooth muscle cells [4]. In our study, macrosomic neonates of diabetic mothers had significantly higher aIMT with lipid alteration.…”

Influence of maternal smoking on neonatal aortic intima-media thickness, serum IGF-I and IGFBP-3 levels

“…A positive association between cIMT and high IGF-I levels has also been observed in acromegalic patients [6]. It has not been clarified yet how the excess of GH/IGF-I induces IMT thickening, but the process could partly be attributed to the direct effects of IGF-I on vascular smooth muscle cells [4]. Growth hormone hypersecretion as well as GH deficiency are characterized by an increased prevalence of CVD [18].…”

Cardiovascular Disease and Sleep-Disordered Breathing in Acromegaly

“…Hypertension affects at least one third (and possibly up to a half) of all patients with acromegaly and is a key negative prognostic factor for mortality [1,12,13,14]. It is present from the earliest stages and is not necessarily influenced by disease duration [15], although it is more common in older subjects, as in the general population.…”

“…It is present from the earliest stages and is not necessarily influenced by disease duration [15], although it is more common in older subjects, as in the general population. An elevation in diastolic pressure is usually the first and predominant finding and may be heralded by changes in vascular dynamics [12]. Minimally invasive vascular studies have revealed an increase in arterial pulse wave velocity (a measure of arterial stiffness) and a reduction in flow-mediated dilatation (signifying impaired endothelial function) in newly diagnosed patients [9], which are believed to be mediated, at least in part, by direct effects of GH and IGF-1 on the vascular tree [16].…”

“…Interestingly, specific assessments of carotid and coronary artery disease in patients with acromegaly have yielded mixed results. For example, Kartal et al [36] and Brevetti et al [12] observed an increase in carotid intima-media thickness in active acromegaly, whereas others have reported no significant increase [37]. Early post-mortem studies suggested an increase in coronary artery atherosclerosis [38,39].…”