The Interrelationships Between Thyroid Dysfunction and Hypogonadism in Men and Boys
- 27 April 2004
- journal article
- review article
- Published by Mary Ann Liebert Inc in Thyroid®
- Vol. 14 (supplement), 17-25
- https://doi.org/10.1089/105072504323024552
Abstract
Thyroid hormone deficiency affects all tissues of the body, including multiple endocrine changes that alter growth hormone, corticotrophin, glucocorticoids, and gonadal function. Primary hypothyroidism is associated with hypogonadotropic hypogonadism, which is reversible with thyroid hormone replacement therapy. In male children follicle-stimulating hormone (FSH) is elevated and associated with testicular enlargement without virilization. Men with primary hypothyroidism have subnormal responses of luteinizing hormone (LH) to gonadotropin-releasing hormone (GnRH) administration and normal response to human chorionic gonadotropin (hCG). Free testosterone concentrations are reduced in men with primary hypothyroidism and thyroid hormone replacement normalizes free testosterone concentrations. In men with primary hypothyroidism, prolactin is not consistently elevated (except in men and children with longstanding severe primary hypothyroidism), but prolactin declines following thyroid hormone replacement therapy. Thyroid hormone is known to affect sex hormone-binding hormonal globulin (SHBG) concentrations. Men with hyperthyroidism have elevated concentrations of testosterone and SHBG. Thyroid hormone therapy in normal men may also duplicate this elevation. In addition estradiol elevations are observed in men with hyperthyroidism, and gynecomastia is common in them as well. In contrast to patients with primary hypothyroidism, men with hyperthyroidism exhibit hyperresponsiveness of LH to GnRH administration and subnormal responses to hCG. Radioactive iodine therapy (RAI) of men treated for thyroid cancer produces a dose-dependent impairment of spermatogenesis and elevation of FSH up to approximately 2 years. Permanent testicular germ cell damage may occur in men treated with high doses of RAI. RAI commonly increases serum concentrations of FSH and LH while reducing inhibin B levels without affecting serum concentrations of testosterone. Thus, radioiodine therapy transiently impairs both germinal and Leydig cell function that usually recover by 18 months posttherapy.Keywords
This publication has 40 references indexed in Scilit:
- A Prospective Controlled Study of the Impact of Hyperthyroidism on Reproductive Function in MalesJournal of Clinical Endocrinology & Metabolism, 2002
- Obstructive Sleep Apnea Due to Endogenous Testosterone Production in a WomanMayo Clinic Proceedings, 1998
- Effects of Thyroid Status on Pituitary Gonadotropin and Testicular Reserve in MenArchives of Andrology, 1997
- Both hyper- and hypogonadotropic hypogonadism occur transiently in acute illness: bio- and immunoactive gonadotropinsJournal of Clinical Endocrinology & Metabolism, 1992
- EFFECTS OF PROTRACTED HYPOTHYROIDISM ON PITUITARY FUNCTION AND STRUCTURE IN ENDEMIC CRETINISMClinical Endocrinology, 1989
- Hypothalamic-pituitary gonadal axis in boys with primary hypothyroidism and macroorchidismThe Journal of Pediatrics, 1988
- The effect of thyroid hormones on growth hormone gene expression in vivo in ratsJournal of Endocrinology, 1987
- GROWTH HORMONE SECRETION AND PLASMA SOMATOMEDIN-C IN PRIMARY HYPOTHYROIDISMClinical Endocrinology, 1983
- TESTICULAR DAMAGE AFTER RADIOACTIVE IODINE (I‐131) THERAPY FOR THYROID CANCERClinical Endocrinology, 1983
- Precocious puberty in juvenile hypothyroidismThe Journal of Pediatrics, 1978