[Absence of antiosteopenic effect of hormone replacement therapy in postmenopausal women]

Several studies suggest that hormone replacement therapy (HRT) stops bone loss in postmenopausal women while increasing their bone mineral density up to 20%; however, there are studies where hormone replacement therapy does not increase bone density, only prevents it.

To analyze the effect of hormone replacement therapy upon bone mineral density of hip and lumbar spine in postmenopausal women.

Clinical files of several patients with sudden menopause diagnosis seen at the Hospital Juarez of Mexico were reviewed in the year 2000. They received hormone replacement therapy of conjugated estrogens and medroxyprogesterone acetate, with annual controls of estradiol in blood, equal or higher than 50 pg/mL and bone mineral density measurement (BMD) with DEXA (dual energy X-ray absortiometry) central (hip and lumbar spine), and at least one control within a period of four years. 89 patients were included and four groups were determined: all of them had basal densitometry in one (group 1), two (group 2), three (group 3), and four years (group 4) of monitoring. The percentage of bone mineral density was calculated in both anatomic areas and per group. In each study group the number or patients that showed gain, loss or whose mineral bone density stayed the same was assessed. The statistical analysis was made using the Student t test.

The 89 patients mean age was of 50.5 (SD +/- 6.42) years. All of them showed spontaneous menopause. The average time of menopause evolution was of 6.9 (SD +/- 4.7) years. The body mass index (BMI) average was of 27.5 (SD +/- 3.97) kg/m2. After admittance, all patients received hormone replacement therapy with conjugated equine estrogens (0.625 mg and medroxyprogesterone acetate 2.5 mg/day). A gain of bone mineral density in the second and third year of treatment in the left hip and in the lumbar spine was observed; however, there were no important differences in any study group when results were treated statistically.

Hormone replacement therapy was not effective to prevent bone loss, neither to increase bone density. Only one treatment was tested, and might be necessary to investigate the effect of other routes of administration or formulations.