This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Di Somma, C. Articles by Lombardi, G. Search for Related Content PubMed PubMed Citation Articles by Di Somma, C. Articles by Lombardi, G.

Bone Marker and Bone Density Responses to Dopamine Agonist Therapy in Hyperprolactinemic Males

Departments of Molecular and Clinical Endocrinology and Oncology (C.D.S., A.C., A.D.S., M.L.L., G.F., R.P., G.L.) and Nuclear Medicine (M.K., M.S.), Federico II University; and the Division of Oncology, A. Cardarelli Hospital (N.P.), Naples 80131, Italy

Address all correspondence and requests for reprints to: Annamaria Colao, M.D., Ph.D., Departments of Molecular and Clinical Endocrinology and Oncology, Federico II University, Via S. Pansini 5, 80131 Naples, Italy.

The aim of this prospective study was to evaluate the bone mineral density (BMD) at lumbar spine and femoral neck levels and biochemical parameters of bone turnover in 20 consecutive hyperprolactinemic males before and after an 18-month treatment with different dopamine agonists. Six patients received bromocriptine at a dose of 2.5–10 mg/day; 7 patients received quinagolide at a dose of 0.075–0.3 mg/day; 7 patients received cabergoline at a dose of 0.5–1.5 mg/week. BMD, serum PRL, testosterone, dihydrotestosterone, and osteocalcin (OC), and urinary cross-linked N-telopeptides of type I collagen (Ntx) levels were measured before and every 6 months during treatment.

At study entry, BMD values were lower in patients than controls at both lumbar spine (0.82 ± 0.03 vs. 1.18 ± 0.01 g/cm²; P < 0.001) and femoral neck (0.85 ± 0.02 vs. 0.92 ± 0.02 g/cm²; P < 0.05) levels. Osteopenia or osteoporosis was diagnosed in 16 patients at the lumbar spine and in 6 of them at the femoral neck level. A significant inverse correlation was found between lumbar spine and femoral neck BMD values and both PRL levels and disease duration (P < 0.01). In the 20 patients, serum OC levels were significantly lower (2.1 ± 0.1 vs. 9.3 ± 2.4 µg/L; P < 0.01), whereas Ntx levels were significantly higher (157.8 ± 1.1 vs. 96.4 ± 7.4 nmol bone collagen equivalent/mmol creatinine; P < 0.001) than control values. A significant inverse correlation was found between serum PRL and OC (P < 0.01), but not Ntx, levels. After 18 months of treatment, serum PRL levels were suppressed, and gonadal function was restored in all 20 patients, as shown by the normalization of serum T (from 2.2 ± 0.2 to 5.0 ± 0.2 µg/L) and dihydrotestosterone (0.3 ± 0.02 vs. 0.5 ± 0.01 nmol/L) levels, without any significant difference among groups. A progressive significant increase in serum OC levels together with a significant decrease in Ntx levels were observed after 6, 12, and 18 months of treatment in the 3 groups of patients. A slight, although significant, increase in BMD values was recorded in all patients after 18 months of bromocriptine, quinagolide, and cabergoline treatment, serum OC levels were normalized after treatment, whereas neither urinary Ntx levels nor BMD values were normalized by 18 months of treatment with dopaminergic agents.

In conclusion, treatment with bromocriptine, quinagolide, and cabergoline for 18 months, although successfull in suppressing serum PRL levels and restoring gonadal function, was unable to restore lumbar spine and femoral neck BMD and normalize Ntx levels. However, BMD was slightly increased during treatment, suggesting that additional bone loss was prevented after treatment of hyperprolactinemia.

This article has been cited by other articles:

				M. P. Gillam, M. E. Molitch, G. Lombardi, and A. Colao Advances in the Treatment of Prolactinomas Endocr. Rev., August 1, 2006; 27(5): 485 - 534. [Abstract] [Full Text] [PDF]

				W. Chowanadisai, S. L. Kelleher, and B. Lonnerdal Maternal Zinc Deficiency Raises Plasma Prolactin Levels in Lactating Rats J. Nutr., June 1, 2004; 134(6): 1314 - 1319. [Abstract] [Full Text] [PDF]

				A. Colao, G. Vitale, P. Cappabianca, F. Briganti, A. Ciccarelli, M. De Rosa, S. Zarrilli, and G. Lombardi Outcome of Cabergoline Treatment in Men with Prolactinoma: Effects of a 24-Month Treatment on Prolactin Levels, Tumor Mass, Recovery of Pituitary Function, and Semen Analysis J. Clin. Endocrinol. Metab., April 1, 2004; 89(4): 1704 - 1711. [Abstract] [Full Text] [PDF]

				J. A. Schlechte Prolactinoma N. Engl. J. Med., November 20, 2003; 349(21): 2035 - 2041. [Full Text] [PDF]

				O. Serri, C. L. Chik, E. Ur, and S. Ezzat Diagnosis and management of hyperprolactinemia Can. Med. Assoc. J., September 16, 2003; 169(6): 575 - 581. [Abstract] [Full Text]

				L. A. Fitzpatrick Secondary Causes of Osteoporosis Mayo Clin. Proc., May 1, 2002; 77(5): 453 - 468. [Abstract] [PDF]