Title:The Effect of Metformin Treatment on Disease Control in Patients with
Acromegaly
Volume: 24
Issue: 6
Author(s): Humeyra Rekali Sahin, Serdar Sahin, Betul Sarac, Cem Sulu, Pinar Kadioglu and Hande Mefkure Ozkaya*
Affiliation:
- Division of Endocrinology, Metabolism and Diabetes, Department of Internal Medicine, Cerrahpasa Faculty of Medicine,
Istanbul University-Cerrahpasa, Istanbul, Turkey
Keywords:
Acromegaly, growth hormone, insulin-like growth factor-1, metformin, somatostatin receptor ligand, adenoma size.
Abstract:
Background: The increase in portal insulin levels has been shown to upregulate
growth hormone receptor expression in the liver, leading to increased insulin-like growth hormone-
1 levels. Metformin inhibits hepatic gluconeogenesis and reduces fasting insulin.
Objectives: We evaluated the effect of metformin treatment in patients with acromegaly on
growth hormone, insulin-like growth hormone-1, and pituitary adenoma size.
Methods: Patients who were followed up with the diagnosis of acromegaly in Istanbul University-
Cerrahpaşa, Cerrahpaşa Medical Faculty were evaluated. The patients were divided into three
groups after pituitary adenectomy as those who received somatostatin receptor ligand and metformin
treatment (group A), somatostatin receptor ligand treatment only (group B), and those
who received metformin treatment only (group C). Groups A and B were compared with each
other, and patients in group C were compared among themselves.
Results: While the median insulin-like growth factor-1 level decreased to 170 ng/ml in Group A
after the treatment, the median insulin-like growth factor-1 level decreased to 229 ng/ml in
Group B, and a statistically significant difference was found between the two groups (p =0.020).
There was no significant difference in post-treatment growth hormone levels and residual adenoma
sizes between groups A and B (p >0.005). In group C, there was no significant difference
in growth hormone values pre-and post-metformin treatment (p =0.078); however, the median
insulin-like growth factor-1 level decreased from 205 ng/ml to 168 ng/ml during metformin
treatment and was found to be statistically significant (p =0.027).
Conclusion: Due to the effect of metformin treatment on insulin-like growth factor-1 values in
patients with acromegaly, it can be used in disease control, as well as diabetes treatment.
