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Comparative effects of continuous combined hormone therapy and tibolone on body composition in postmenopausal women
S Ziaei1, M Moaya, S Faghihzadeh
1Department of Obstetrics & Gynecology, Tarbiat Modares University, Tehran, Iran.
Objective:
To compare the effects of tibolone with those of continuous combined hormone replacement therapy (HT) on body composition in postmenopausal women.
Methods:
One hundred and fifty postmenopausal women were enrolled in a randomized, controlled trial to compare the effects of tibolone with continuous combined HT on body composition. Patients were randomly allocated into three groups and followed for 9 months. Of the subjects included, 50 women received 2.5 mg tibolone plus one Cal+D tablet (500 mg calcium and 200 IU vitamin D) daily, 50 women received 0.625 mg conjugated equine estrogen and 2.5 mg medroxyprogesterone acetate (CEE/MPA) plus one Cal+D tablet daily, and the rest (50 women) received only one Cal+D tablet and served as a control group. Body composition was evaluated with measurements of body mass index (BMI), weight, waist-to-hip ratio (WHR), fat mass and fat-free mass (FFM) before and after the intervention. Measurements of body fat mass percentage, fat mass, body fat-free mass percentage and fat-free mass (FFM) were assessed by measurement of skin-fold thickness.
Results:
Tibolone significantly increased weight, BMI and FFM and decreased WHR after the treatment in comparison with baseline (p < 0.05). However, only weight and BMI increased significantly in the CEE/MPA group after the treatment (p < 0.05). There were significant increases in weight, BMI and fat mass in the control group after 9 months. In the comparison of the parameters after the treatment between the three groups, tibolone significantly increased FFM compared with the control and CEE/MPA groups (p < 0.01).
Conclusions:
The effect of tibolone on body composition is favorable and therefore tibolone may be regarded as an alternative to continuous combined hormone therapy in postmenopausal women.
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