Cost-effectiveness of hormone replacement therapy after the menopause.

The net resource costs and net health benefits of treating perimenopausal women with hormone replacement therapy were evaluated within the framework of cost-effectiveness analysis. Data from the epidemiological literature were used to estimate changes in discounted life expectancy from hip fracture, ischaemic heart disease and breast cancer that are associated with hormone replacement therapy under a variety of assumptions. Economic data were used to estimate changes in total discounted costs that result from the use of hormone replacement therapy. For women with a previous hysterectomy, 10- and 15-year courses of unopposed oestrogen were evaluated. The baseline assumptions for unopposed oestrogen were that breast cancer incidence would be increased for current users by 36% and that deaths from ischaemic heart disease would be reduced by 50% relative to non-users. Under these assumptions, oestrogen replacement therapy was found to be cost-effective, with ratios ranging from $9130 to $12,620 per additional year of life saved. For women who have not had a hysterectomy, 10- and 15-year courses of oestrogen combined with progestin were evaluated. The baseline assumptions for combined therapy were that breast cancer incidence and ischaemic heart disease deaths were unaffected. Under these assumptions, combined therapy was more costly, with ratios ranging from $86,100 to $88,500. Unless combined therapy is found to confer protection against ischaemic heart disease, the most cost-effective strategies for women with no prior hysterectomy may involve screening perimenopausal women to detect women at highest risk of hip fracture followed by selective treatment.