title: The effect of one-year cross-sex hormonal treatment on bone metabolism and serum insulin-like growth factor-1 in transsexuals.
abstract: The effects of treatment with estrogens and antiandrogens in male to female (M-->F) transsexuals and androgens in female to male (F-->M) transsexuals on their respective bone metabolism, bone mineral density (BMD), serum insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) levels were investigated. BMD and variables of bone turnover in serum were measured at baseline and after 3 months (except for BMD) and 1 yr of treatment in 56 M-->F and 35 F-->M transsexuals. Serum IGF-I, IGFBP-3, and propeptide of type I procollagen (P1CP) were measured at baseline and after 1 yr of treatment in 10 M-->F and 10 F-->M transsexuals. In M-->F, BMD increased significantly. Bone turnover decreased, as shown by a significant decline in levels of osteocalcin, alkaline phosphatase, P1CP, and fasting urinary calcium/creatinine and hydroxyproline/creatinine ratios. Serum IGF-I levels decreased significantly without significant changes in IGFBP-3 levels. In F-->M, BMD did not change. Bone formation increased, as suggested by an increase in alkaline phosphatase and a borderline increase in P1CP values. IGF-I levels increased significantly, whereas no significant changes were seen in IGFBP-3 levels. We conclude that in males, estrogens (in combination with antiandrogens) decrease bone turnover, with a subsequent increase in BMD and a decrease in serum IGF-I. In females, testosterone administration increases bone formation, but this is not reflected in an increased BMD, whereas serum IGF-I increases.
authors.affiliation: Department of Endocrinology, Free University Hospital, Amsterdam, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: van Kesteren
authors.forename: P
authors.initials: P
authors.lastname: Lips
authors.forename: W
authors.initials: W
authors.lastname: Deville
authors.forename: C
authors.initials: C
authors.lastname: Popp-Snijders
authors.forename: H
authors.initials: H
authors.lastname: Asscheman
authors.forename: J
authors.initials: J
authors.lastname: Megens
authors.forename: L
authors.initials: L
authors.lastname: Gooren
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D000726:Androgen Antagonists / Q000494:pharmacology; D000728:Androgens / Q000494:pharmacology; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D004967:Estrogens / Q000494:pharmacology; D005260:Female; D012739:Gonadal Steroid Hormones / Q000494:pharmacology*; D006728:Hormones / Q000097:blood; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D014189:Transsexualism / Q000378:metabolism*
chemical_list: D000726:Androgen Antagonists; D000728:Androgens; D004967:Estrogens; D012739:Gonadal Steroid Hormones; D006728:Hormones; D018969:Insulin-Like Growth Factor Binding Proteins; D007334:Insulin-Like Growth Factor I; D000469:Alkaline Phosphatase