Hypogonadism in patients with acromegaly: data from the multi-centre acromegaly registry pilot study

OBJECTIVE Because acromegaly is an uncommon disorder, epidemiological data regarding the demographics of the disease such as the prevalence of hypogon adism have been limited. In order to derive clinical and epidemiological in formation, including underlying hormonal factors, regarding hypogonadism in patients with acromegaly, we performed a pilot study designed to develop a multi-centre acromegaly patient registry. DESIGN AND MEASUREMENTS Medical records of patients with acromegaly seen be tween 1976 and 1996 at three Institutions were reviewed, and data were ente red into a database using a secure internet website. Hypogonadism was defin ed as amenorrhoea in women and testosterone deficiency in men. Subanalysis was performed in patients with microadenomas and women less than 50 years o f age, to include women of reproductive age. RESULTS Information was available on 363 patients, of whom 54% were women. The mean age at diagnosis was 41 +/- 13 years. In subjects less than 50 yea rs of age, hypogonadism was present in 59%. Hyperprolactinaemia was present in 45% and 21% of hypogonadal and eugonadal patients of reproductive age, respectively (P = 0.0003). GH levels were higher in patients with hypogonad ism (P = 0.03). In patients < 50 years of age with microadenomas, hypogonad ism was present in nine of the 22 (41%) patients, including 55% of the wome n and 27% of the men (P = ns). Hyperprolactinaemia was present in three of the 10 and four of the 14 of microadenoma patients with hypogonadism and eu gonadism, respectively. CONCLUSION We developed a web-based acromegaly patient registry and used it to show that hypogonadism is a frequent consequence of acromegaly, even in patients with microadenomas, who are not at risk from hypopituitarism due to local mass effects. We also demonstrated that prolactin and GH hypersecr etion contribute to the pathogenesis of hypogonadism in acromegaly, and tha t hypogonadism may occur in microadenoma patients even in the absence of hy perprolactinaemia.