Objective: At the onset of menopause, weight-gain and the aggravation of certain cardiovascular risk factors are frequently observed. The aim of this study was to examine the metabolic effects of combined hormone replacement therapy (17beta-oestradiol transdermic 50 microg for 21 days and oral medroxyprogesterone acetate 5 mg from day 10 to 21) using, in particular, indirect calorimetry.
Methods: Patients (21; 12 substituted and nine controls) were studied twice (3 months apart) during an oral glucose load (75 g).
Results: Total body weight was unaltered after 3 months in the control group, whereas a fat-loss of 2.1+/-0.2 kg and a decrease of the waist:hip ratio were observed in the substituted group. In the latter group, a significant increase in lipid oxidation was observed (0.58+/-0.06 mg/kg/min before and 0.75+/-0.04 mg/kg/min after substitution P<0.05), whilst total energy expenditure and thermogenesis were also increased. Glucose, lipid and protein oxidation remained stable during three months in the control group. The insulin response to an oral glucose load diminished by 30% with hormone replacement therapy (102.3+/-32.8 mmicro/l versus 71.4+/-20.0 mmicro/l). Total and LDL-cholesterol improved after hormone replacement therapy whereas plasma triglycerides were not altered.
Conclusions: Combined hormone replacement therapy not only prevented weight-gain, but favored weight-loss by significantly increasing lipid oxidation after 3 months of treatment. It also favourably influenced the insulin response, plasma lipids and energy expenditure.