Association Between Hormone Therapy and Weight Gain in the Menopause Transition and After Menopause: A Systematic Review and Meta-Analysis

Objectives: to conduct a systematic review and meta-analysis in order to assess whether hormone therapy (HT) increases weight in women in the menopausal transition and after menopause. Method: this article proposes an update to the systematic review published in 2005 by the Cochrane Library (Kongnyuy EJ et al 2005) with reference to studies assessing weight changes in women receiving HT from 1986 to 2005. Following PRISMA recommendations, we included randomized controlled trials (RCTs) ) from May 2005 onwards from Medline, Embase, and the Cochrane CENTRAL databases. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated. Two authors independently assessed the risk of biases in the selected studies. Results: ten RCTs were included, totaling 2,588 HT users and 764 non-users. Different regimens, dosages, and routes of administration in HT users were analyzed and compared to non-users. The results did not show statistically significant differences for most of the HT regimens evaluated. There was significant weight gain only in patients using EEC alone at dosages of 0.45 mg/day and 0.3 mg/day when compared to placebo (p 0.01); as well as in patients receiving esto-progestative combinations of 0.5 mg/day 17-beta-estradiol (E2) + 100 mg/day progesterone, with a 0.7 kg weight increase (p 0.032). On the other hand, the combinations of 1 mg/day estradiol valerate + 3 mg/day drospirenone showed a -1.0 kg reduction (p = 0.04), whereas a -0.2 kg reduction (p = 0.001) was identified in patients using 1 mg /day estradiol (E) + 0.5 mg norethisterone acetate (NETA). Tibolone therapy showed no statistically significant changes in weight. After performing a meta-analysis, the comparative results between users and non-users showed that there was a slight weight increase (+0.279 kg ; CI -1.71 to 2.27) in patients using 0.625 mg/day conjugated equine estrogen (CEE) + 2.5 mg/day medroxyprogesterone acetate (MPA). As for the patients receiving 2.5 mg/day Tibolone, weight gain (+0.670 kg; CI from -1.14 to 2.48) was also observed in them. However, these increases were not significant when compared to non-HT users. Conclusions: most regimens studied showed that patients using HT in the menopausal transition and after menopause did not show significant weight gain. The only combination that showed weight gain was 0.5 mg/day 17-beta-estradiol (E2) + 100 mg/day progesterone observed, while there was weight reduction in patients using 1 mg/day estradiol va