title: Long-term effects of transdermal and oral hormone replacement therapy on postmenopausal bone loss.
abstract: Transdermal hormone replacement therapy (HRT) is now an accepted form of treatment, but the long-term skeletal effects have not been assessed. Sixty-six early postmenopausal women were randomized to receive either transdermal HRT (continuous 17 beta-oestradiol 0.05 mg/day, with 0.25 mg/day of norethisterone acetate added for 14 days of each 28-day cycle) or oral HRT (continuous conjugated equine oestrogens 0.625 mg/day, with 0.15 mg/day dl-norgestrel added for 12 days of each 28-day cycle). Treatment was given for 3 years and 30 matched untreated women were studied concurrently as a control group. Bone density was measured in the lumbar spine and proximal femur by dual-photon absorptiometry at 6-monthly intervals. Bone turnover was assessed by measurement of biochemical markers. At 3 years bone density had declined by 4% in the lumbar spine and by more than 5% in the femoral neck in the untreated group. By comparison bone density increased in both treatment groups at both sites (p < 0.001 vs. untreated) and biochemical measurements indicated a significant reduction in bone turnover. There were no significant differences between the treatment groups. Twelve per cent of women on transdermal or oral treatments lost a significant amount of bone from the femoral neck by 3 years despite adequate compliance. Women taking therapy primarily for hip fracture prevention may require a follow-up bone density measurement to establish the efficacy of treatment.
authors.affiliation: Wynn Institute for Metabolic Research, London, UK.
authors.forename: T C
authors.initials: TC
authors.lastname: Hillard
authors.forename: S J
authors.initials: SJ
authors.lastname: Whitcroft
authors.forename: M S
authors.initials: MS
authors.lastname: Marsh
authors.forename: M C
authors.initials: MC
authors.lastname: Ellerington
authors.forename: B
authors.initials: B
authors.lastname: Lees
authors.forename: M I
authors.initials: MI
authors.lastname: Whitehead
authors.forename: J C
authors.initials: JC
authors.lastname: Stevenson
mesh_terms: D000279:Administration, Cutaneous; D000284:Administration, Oral; D015519:Bone Density; D015914:Estrogen Replacement Therapy; D005260:Female; D005272:Femur Neck / Q000473:pathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000517:prevention & control*; D017698:Postmenopause; D011446:Prospective Studies