The influence of hormone replacement therapy (HRT) on serum leptin concentration in postmenopausal women

Abstract Objective: This study aimed to evaluate the influence of hormone replacement therapy (HRT), the estradiol concentration and body mass index (BMI, kg/m 2 ) on the serum leptin concentration in postmenopausal women. Subjects and methods: 352 healthy postmenopausal women (mean age, 60.9±8.5 years) participated in this comparative study. 71 (30%) women (mean age 55.9±8.3 years) had taken HRT, while 281 (70%) women (mean age, 59.1±10.6 years) had not. Baseline characteristics -age, weight, height, BMI (≥25 or n =130); (b) postmenopausal women not on HRT with a BMI≥25 ( n =151); (c) postmenopausal women on HRT with a BMI n =48); and (d) postmenopausal women on HRT with a BMI ≥25 ( n =23). Leptin concentrations were subsequently analysed in relation to BMI and age and BMI and estradiol concentrations to determine any independent effect of these variables. Results: The women taking HRT had a significantly lower mean age, weight, BMI and follicle stimulating hormone concentration than those who were not taking HRT. Furthermore, they had a higher mean height and serum estradiol value, but a significantly lower serum leptin concentration. After controlling for BMI, neither the use of HRT nor the estradiol concentration was found to be related to the leptin value (group (a) versus (c) and group (b) versus (d)), but there were significant differences in leptin concentrations between HRT users with BMI ≥25 and BMI Conclusions: Leptin concentrations are significantly higher in obese postmenopausal women than in their non-obese counterparts. Serum leptin concentrations are not influenced by HRT use or estradiol concentrations. Further studies are needed to elucidate the role of HRT and estrogen on serum leptin concentrations.