Resistin and leptin levels in acromegaly: lack of correlation with echocardiographic findings

Acromegaly, inflammation and cardiovascular disease: a review

Acromegaly is characterized by Growth Hormone (GH) and Insulin-like Growth Factor 1 (IGF-1) excess. Uncontrolled acromegaly is associated with a strongly increased risk of cardiovascular disease (CVD), and numerous cardiovascular risk factors remain present after remission. GH and IGF-1 have numerous effects on the immune and cardiovascular system. Since endothelial damage and systemic inflammation are strongly linked to the development of CVD, and have been suggested to be present in both controlled as uncontrolled acromegaly, they may explain the presence of both micro- and macrovascular dysfunction in these patients. In addition, these changes seem to be only partially reversible after remission, as illustrated by the often reported presence of endothelial dysfunction and microvascular damage in controlled acromegaly. Previous studies suggest that insulin resistance, oxidative stress, and endothelial dysfunction are involved in the development of CVD in acromegaly. Not surprisingly, these processes are associated with systemic inflammation and respond to GH/IGF-1 normalizing treatment.

Serum visfatin levels in acromegaly: Correlation with disease activity and metabolic alterations

OBJECTIVE

The studies that have extensively evaluated the relation between adipokines and metabolic parameters in acromegaly treatment are quite discordant. We aimed to evaluate and correlate a set of selected adipokines, known to have a metabolic role, with the disease activity, metabolic status and treatment modalities.

DESIGN

Data of 56 consecutive acromegalic patients (31 M and 25 F; aged 54 ± 12 years), admitted to the section of Endocrinology of the University of Palermo during the years 2005-2014, including 16 newly diagnosed untreated (ND), 21 during therapy with somatostatin analogues (SA), 12 with pegvisomant (PE) and 7 after surgical treatment (SU), grouped into uncontrolled (group A: No. 33) and controlled (group B: No. 23) were evaluated. Anthropometric and metabolic parameters, insulin sensitivity indexes, visceral adiposity index (VAI), leptin, soluble leptin receptor, adiponectin, visfatin, resistin, adipsin and non-esterified fatty acids (NEFAs) were assessed. In a subgroup of 21 subjects, the insulin sensitivity index (M value) derived from euglycemic clamp was calculated.

RESULTS

Group A showed higher Homa-IR (p < 0.001), VAI (p < 0.001), triglycerides (p < 0.001), visfatin (p < 0.001), and NEFAs (p < 0.001) and lower ISI Matsuda (p < 0.001), M value (p < 0.001), HDL cholesterol (p < 0.001) and leptin (p < 0.001) than group B. ND patients showed higher VAI, triglycerides, Homa-IR, and visfatin and lower ISI Matsuda, M-value, and leptin compared to other groups (all p < 0.050), while no differences were found among SA, PE and SU patients. IGF-1 (p = 0.048), M-value (p = 0.0029) and VAI (p = 0.010) were independently associated with visfatin, while only ISI Matsuda (p = 0.019) was associated with leptin.

CONCLUSIONS

In acromegaly visfatin could be considered a useful index of disease activity and metabolic alterations, such as insulin resistance and adipose dysfunction, regardless of the type of treatment.