Comparative evaluation of several parameters of glycemic homeostasis in patients with functional pituitary adenomas

• Main Authors: Rostislavovna Mikityuk, Oksana Olegovna Khizhnyak, Tatiana Ninelovna Sulima
• Format: Article
• Language: English
• Published: Endocrinology Research Centre 2014-03-01
• Series: Сахарный диабет
• Subjects: pituitary adenoma; acromegaly; prolactinoma; insulin resistance; glycemic homeostasis
• Online Access: https://dia-endojournals.ru/dia/article/viewFile/6309/4319
• ISSN: 2072-0351; 2072-0378

Aim. To investigate glycemic homeostasis in patients with acromegaly and hyperprolactinaemia due to functional pituitary adenoma. Materials and Methods. We enrolled 48 patients with somatotropinoma (Group 1), 19 patients with somatomammotropinoma (Group 2) and 24 patients with prolactinoma (Group 3) with no history of glycemic disorders. Median age was 48.63?9.98 years; median disease duration was 13.1?6.9 years. The comparison group was composed of overweight or obese patients (n=75). We conducted a comparative analysis of glycemic parameters (Glc0, immunoreactive insulin, HOMA2_S%, HOMA2_B% и HOMA2_IR, Ssum and S under isolated segments of the glycemic curve). We also tested their correlation with plasma levels of growth hormone, prolactin and IGF-1. Results. We detected hyperinsulinemia (>20 ?U/mL) in 35.1% of participants from Group 1, 33.3% and 25% from groups 2 and 3, respectively. There was no statistically significant difference between glycemic parameters of the study groups, though patients were mildly insulin resistant (HOMA2_IR 1.88 to 2.38 units) independantly from tumour secretory activity. Groups 1 and 2 were characterized by significantly higher fasting blood glucose levels vs. comparison group (though still within the reference values), and glucose homeostasis was maintained with lower activity of pancreatic ?-cells. Average Ssumanalysis showed lower glucose tolerance in groups 1 and 2 vs. Group 3. Median S values under isolated glycemic curve segments were significantly higher than in comparison group. Plasma levels of growth hormone did not correlate with Ssum and S parameters in groups 1 and 2. There was a linear correlation between Ssum and plasma IGF-1 levels in patients from Group 1 (r=0.45; p=0.006). We also noted that Ssum had a non-linear correlation with plasma prolactin levels in patients from Group 3 (r=0.41; p