Endocrine Abstracts

Introduction: Active acromegaly is associated with increased mortality, which has been attributed largely to cardiovascular disease.

Aims: To evaluate the effects of chronic excess of GH and IGF1 on lipid metabolism in patients with active acromegaly.

Subjects and methods: Ninety-seven patients (37 men and 60 women; aged 18–76 years) with macroadenoma of hypophysis (67 – somatotropinoma, 30 – somatomammotropinoma) were under investigation. Blood samples for GH, IGF1, total cholesterol (TC), triglycerides (T), HDL-C, Apo A-I and Apo B were taken in fasting state. LDL-C and VLDL-C were calculated using the Friedwald formula. Disease activity was evaluated by means of OGTT according to the Consensus Conference criteria. Data are given as M±SE and multiple regression model equations.

Results: In 40.4% of patients with somatotropinoma (GH – 22.8±3.5 ng/ml; IGF1 – 620.81±301.30 ng/ml) and somatomamotropinoma (GH – 26.3±5.3 ng/ml; IGF1 – 651.69±295.64 ng/ml) different types of dyslipidemias (WHO of classification) were found out: IIa type in 18.9%; III type – in 15.8%, and IV type – in 5.3% of patients. Moderately elevated level of TC, T, LDL-C, and VLDL-C was appropriate to both groups of patients with macroadenoma. It was found out nonlinear regression between HDL-C, ApoA-I, ApoB and IGF1 approximated by equations: HDL-C≈1/(0.7+30.5/IGF1) (R2=52.8%, P=0.002); Apo A-I ≈1/(0.6+16.3/IGF1)(R2=22.1%, P=0.01); ApoB=2.07−0.17*ln(IGF1)(R2=21.2%, P=0.01).

Conclusion: The GH hypersecretion is associated with altered lipid profile. IGF1 mainly predetermines the level of HDL-C, Apo-I and ApoB lipoproteins. Patients with acromegalia are at increased cardiovascular risk through the atherogenic dyslipidemias that may accompany the chronic excess of GH.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.