Estradiol mediates the association of waist-to-hip ratio, but not body fat percentage, with menopause-related symptoms in Chinese women aged 40-60 years.
Abstract
Background Menopause-related symptoms adversely affect quality of life. Although both overall and central adiposity have been associated with menopausal symptoms, the role of estradiol in these associations remains unclear. Methods This single-center cross-sectional study included 600 women aged 40-60 years who attended the International Peace Maternity and Child Health Hospital, Shanghai, China. Participants were classified into premenopausal and postmenopausal groups according to the Stages of Reproductive Aging Workshop +10 (STRAW + 10) criteria. Menopause-related symptoms were assessed using the modified Kupperman Index (KMI). Body fat percentage (PBF) and waist-to-hip ratio (WHR) were measured using a bioelectrical impedance analyzer, and serum reproductive hormone levels, including estradiol (E2), were determined by chemiluminescent immunoassay. Multivariable linear regression models were used to examine the association between body composition parameters and KMI scores. Mediation analyses were performed to evaluate the mediating role of E2, and stratified analyses by menopausal status were conducted to assess the consistency of these associations. Results After adjustment for potential confounders, higher WHR was independently associated with greater menopause-related symptom severity (β = 12.058, 95% CI: 1.816 to 22.300, P = 0.021), and higher PBF showed a similar association (β = 0.103, 95% CI: 0.011 to 0.196, P = 0.029). Mediation analyses revealed that E2 significantly mediated the association between WHR and KMI scores (indirect effect = 2.202, 95% CI: 0.520 to 4.323, P = 0.011; mediation proportion = 17.8%), whereas no significant mediating effect was observed for PBF (indirect effect = 0.008, 95% CI: -0.007 to 0.025, P = 0.296). Stratified analyses suggested that these associations were more evident among premenopausal women, although no significant interaction by menopausal status was observed. Conclusion Both overall and central adiposity were associated with more severe menopause-related symptoms; however, estradiol mediated only the association between central adiposity and symptom severity. These findings suggest that different adiposity patterns may be associated with menopausal symptoms through distinct biological pathways.