Targeting of hormone replacement therapy immediately after menopause

The aim of this study was to model the effect of short (3-year) treatments with hormone replacement therapy (HRT) at the time of menopause on the risk of osteoporotic fracture, and to assess the impact of strategies to target high-risk individuals. From the relationship between bone mineral density (BMD) and fracture risk, treatment that increased bone mineral density at the hip by 6% over untreated women would save 35 vertebral, 62 hip, 13 proximal humeral, and 16 forearm fractures per 1000 women. The number needed to treat (NNT) to prevent one of these fractures was 8. The NNT fell modestly by targeting HRT to women with low bone mass or osteoporosis (NNT 6 and 5, respectively). The gains in fractures saved from targeting women with low bone mass or osteoporosis were offset by the requirement for assessment by BMD. Changes in the assumptions about the efficacy of HRT had a modest impact on fractures saved compared with the effect of changing assumptions concerning the offset of effect when treatment was stopped. We conclude that comparatively short courses of HRT might be effectively offered to all suitable women at menopause provided that the effects on bone persist when treatment is stopped.