Background: Thiazolidinediones increase adiponectin concentrations, improve insulin sensitivity and fatty liver disease (reflected by decreased alanine aminotransferase [ALT] activity) in type 2 diabetes. This study was performed to test the effect of neurosurgery in acromegaly (sharing at baseline insulin resistance but not increased visceral fat with type 2 diabetes) on insulin sensitivity, adiponectin concentrations and ALT activity.
Methods: Sixteen patients with acromegaly undergoing pituitary surgery (and 16 patients with type 2 diabetes treated with pioglitazone) were included. Insulin sensitivity, adiponectin concentrations and ALT activity were determined at baseline and after 4 months.
Results: Pituitary surgery in acromegalic patients increased adiponectin concentrations from mean (+/-S.D.) 9.3+/-3.8 to 10.2+/-4.4 mg/L (p<0.05). HOMA scores fell from 6.8+/-4 at baseline to 3.5+/-0.9 following neurosurgery (p<0.005) and ALT activity decreased from median (range) 21 (13-30) to 13 (10-42) U/L (p<0.05). In type 2 diabetics, pioglitazone treatment increased adiponectin concentrations; HOMA scores and ALT activity fell significantly.
Conclusion: Pituitary surgery in patients with acromegaly led to a marked increase in insulin sensitivity and a slight increase in adiponectin serum concentrations, whereas ALT activity significantly decreased.