Effects of HRT on serum levels of IGF-I in postmenopausal women

Posaci C., ALTUNYURT S., İŞLEKEL G. H., Onvural A.

MATURITAS, vol.40, no.1, pp.69-74, 2001 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 40 Issue: 1
  • Publication Date: 2001
  • Doi Number: 10.1016/s0378-5122(01)00230-4
  • Journal Name: MATURITAS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.69-74
  • Keywords: hormone replacement therapy, IGF-I, oral and transdermal, GROWTH-FACTOR-I, BONE-MINERAL DENSITY, ESTROGEN REPLACEMENT THERAPY, ADVANCED BREAST-CANCER, HORMONE SECRETION, PLASMA-LEVELS, PERIMENOPAUSAL WOMEN, BINDING PROTEINS, FACTOR (IGF)-I, SEX
  • Dokuz Eylül University Affiliated: Yes

Abstract

Objectives: It is thought that insulin-like growth factor-1 (IGF-I) stimulates bone formation. We aimed to determine the effects of oral and transdermal hormone replacement therapy (HRT) on serum IGF-I levels and to investigate the effects of basal IGF-I levels on the levels obtained at the end of the therapy. Methods: Sixty-six postmenopausal women were administered either oral (n = 44) or transdermal (n = 22) HRT for 6 months. Serum levels of IGF-I were determined before and after HRT in all subjects. Groups were divided into two subgroups according to the median value of serum IGF-I levels (basal IGF-I levels above or below the median value). The increase of IGF-1 levels after HRT were calculated (%) for all women. Mean increases of subgroups were compared. Furthermore, study groups were divided into three subgroups according to the changing of IGF-I (increase > 25%, between 25% increase and 25% decrease and decrease > 25%). Mean basal IGF-I levels of these three subgroups were compared. Results: Mean serum levels of IGF-I before and after HRT were not significantly different in both oral and transdermal groups (P > 0.05). Mean increases of IGF-I after HRT for the patients with low basal IGF-I levels, were 65% in oral and 77% in transdermal groups. However, mean increase of the patients with high basal IGF-I levels were - 8 and - 16% respectively. Moreover, mean level of basal IGF-I was significantly low in women who have more than a 25% increase after HRT (P < 0.05). Conclusion: HRT seems to significantly increase serum levels of IGF-I in postmenopausal women with low basal levels of IGF-1. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.