Continuous combined oestrogen/progestin therapy is well tolerated and increases bone density at the hip and spine in post-menopausal osteoporosis

OBJECTIVES Although oestrogen/progestin therapy is effective prophylaxis against post-menopausal osteoporosis, its efficacy in the treatment of established disease is uncertain. In addition, cyclical oestrogen/progestin regimens are associated with low rates of patient acceptance. The present study assesses the acceptability of, and skeletal response to, continuous combined hormone replacement therapy in osteoporotic late post-menopausal women. DESIGN Retrospective, controlled study. PATIENTS One hundred and four osteoporotic late postmenopausal women treated with continuous combined hormone replacement therapy (5 mg medroxyprogester-one acetate daily and either 0·625 mg oral conjugated oestrogens or 50 μg transdermal oestradiol daily) were followed for an average of 1 year (range 2–38 months). Control subjects were 19 healthy normal women matched for menopausal age and weight. MEASUREMENTS Adverse effects and compliance rate were monitored. Baseline and 1-year measurements of lumbar spine bone mineral density (BMD) were performed using dual-energy X-ray absorptiometry in 51 women, 22 of whom also had measurements at 2 years. Twenty-eight women had proximal femur scans at baseline and 1 year. RESULTS Eighty-six per cent of women continued to take continuous combined hormone replacement therapy at the end of follow-up. Mastalgia (44%) and vaginal bleeding (29%), the most common side-effects, were minor and self-limiting in virtually all women. Spinal BMD increased by 7·1 ± 0·8% (mean±SEM P < 0·001) at 1 year and by 8·9 ± 1·5% (P < 0·001) at 2 years. In the proximal femur, BMD increased by 2·9 ± 0·9% at the femoral neck (P= 0·01) and by 2·5±0·9% (P= 0·001) at the trochanter at 1 year. BMD tended to decline in the control group. Among the women taking hormone replacement therapy, the increase in spinal BMD was similar in those treated with 0·3–0·44 mg/day of conjugated equine oestrogens to those receiving 0·45–0·625 mg/day. CONCLUSION Continuous combined hormone replacement therapy is an acceptable therapy to osteoporotic late post-menopausal women and produces substantial increases in lumbar spine and proximal femoral bone mineral density.