THE EFFECTS OF PROLONGED BROMOCRIPTINE ADMINISTRATION ON GLYCEMIC CONTROL IN PATIENTS WITH HYPERPROLACTINEMIA

Previous studies have shown that treatment with quick-release formulation of bromocriptine improves glycaemic control and reduced body weight in obese type 2 diabetes patients. Our aim was to assess the effects of prolonged bromocriptine administration on glycaemic homeostasis in patients with hyperprolactinemia. We assessed 11 non-diabetic patients with hyperprolactinemia (8 women and 3 men, aged 31-67 years); 10 patients had a pituitary tumour and one had a craniopharyngioma. A galactorrhoea-amenorrhoea syndrome was observed in 7 women. Fasting plasma glucose, serum prolactin and computed tomography of pituitary were determined at baseline and after 12 months treatment with bromocriptine. At baseline, the mean (+/- SD) fasting plasma glucose was 102.91 +/- 7.31 mg/di, serum prolactin 161.80 +/- 56.91 ng/ml and maximum diameter of the tumours 10.67 +/- 4.73 mm. After 12 months of treatment, fasting plasma glucose was 90.27 +/- 8.91 mg/dl, serum prolactin 26.38 +/- 2.61 ng/ml and maximum diameter of the tumours 5.55 +/- 1.12 mm. In our study, the treatment with bromocriptine generated significant changes in plasma glucose, serum prolactin and maximum diameter of the tumours. Circulating plasma glucose concentrations were significantly lower (p<0.05) following treatment with prolonged bromocriptine, but it is clear from the results that the change was modest in magnitude.