Hormonal replacement therapy reduces forearm fracture incidence in recent postmenopausal women - results of the Danish Osteoporosis Prevention Study

Objectives: To study the fracture reducing potential of hormonal replacemen t therapy (HRT) in recent postmenopausal women in a primary preventive scen ario. Methods: Prospective controlled comprehensive cohort trial: 2016 heal thy women aged 45-58 years, from three to 24 months past last menstrual ble eding were recruited from a random sample of the background population. Mea n age was 50.8 +/- 2.8 years, and the number of person years followed was 9 335.3. There were two main study arms: a randomised arm (randomised to HRT; n = 502, or not; II = 504) and a non-randomised arm (on HRT: n = 221, or n ot; n = 789 by own choice). First line HRT was oral sequential oestradiol/n orethisterone in women with intact uterus and oral continuous oestradiol in hysterectomised women. Results: After five years, a total of 156 fractures were sustained by 140 women. There were 51 forearm Fractures in 51 women. By intention-to-treat analysis (n = 2016), overall fracture risk was border line statistically significantly reduced (RR = 0.73, 95% CI: 0.50-1.05), an d forearm fracture risk was significantly reduced (RR = 0.45, 95% CI: 0.22- 0.90) with HRT. Restricting the analysis to women who had adhered to their initial allocation of either HRT (n = 395) or no HRT (n = 977) showed a sig nificant reduction in both the overall fracture risk (RR = 0.61, 95% CI: 0. 39-0.97) and the risk of forearm fractures (RR = 0.24, 95% CI: 0.09-0.69). Compliance with HRT was 65% after five years. Conclusions: It is possible t o reduce the number of forearm fractures and possibly the total number of f ractures in recent postmenopausal women by use of HRT as primary prevention . (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.