A DOUBLE-BLIND RANDOMIZED CONTROLLED TRIAL OF THE EFFECTS OF MEDROXYPROGESTERONE ACETATE ON BONE-DENSITY OF WOMEN TAKING ESTROGEN REPLACEMENT THERAPY

Objective To assess the effects of medroxyprogesterone acetate on bone density in women who have had a hysterectomy Design Randomised, doubl e-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg , 20 mg or placebo as an adjunct to oestrogen therapy. Participants On e hundred and twenty-three women, aged 18 to 45 years and currently re ceiving daily oestrogen, who presented at a university-based rheumatol ogy practice. Interventions The women were randomly assigned to receiv e either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beg inning on day 15 of each month for one year. Forty-one women were rand omised into each group. Main outcome measure The primary outcome measu rement was the percentage of change from baseline in bone mineral dens ity of the lumbar spine (L2-L4). Secondary outcome measures included d ifferences in femoral neck bone density, cholesterol and triglyceride levels between groups. Results At one year, change in bone mineral den sity did not differ between either the treatment or placebo groups. Me droxyprogesterone acetate 20 mg and 10 mg led to statistically signifi cant reductions in very low density lipoprotein cholesterol, total tri glycerides, and very low density lipoprotein triglycerides when compar ed with placebo. Medroxyprogesterone acetate 20 mg also led to a stati stically significant reduction in high density lipoprotein cholesterol , high density lipoprotein-2 cholesterol, and high density lipoprotein -2 triglycerides. Conclusions Medroxyprogesterone acetate at either do se as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, h owever, did reduce high density lipoprotein cholestrol and therefore m ay increase cardiovascular risk.