Fighera Tayane M, Santos Betânia R, Motta Letícia, Casanova Gislaine, Spritzer Poli Mara
From the Gynecological Endocrinology Unit, Division of Endocrinology, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil.
Menopause. 2023 Mar 1;30(3):317-322. doi: 10.1097/GME.0000000000002126. Epub 2022 Dec 13.
The aim of this study was to explore body composition parameters and hormone levels as risk factors for low bone mass (osteopenia/osteoporosis) in postmenopausal women.
We analyzed biorepository samples from 139 postmenopausal women with no clinical evidence of cardiovascular disease. Inclusion criteria were menopause occurring after 40 years of age and no use of hormone therapy in the past 3 months. Bone mineral density and body composition were assessed by dual-energy x-ray absorptiometry. Sex hormone-binding globulin (SHBG) and follicle-stimulating hormone (FSH) levels were measured in all participants. Serum estradiol was measured by gas chromatography/tandem mass spectrometry in a subset of 57 participants. Free estrogen index was calculated by dividing estradiol by SHBG × 100.
Body mass index (25.0 [22.5-26.5] vs 27.7 [26.6-31.9] kg/m 2 , P < 0.001), estradiol (3.0 [2.7-4.5] vs 6.0 [2.7-15.0] pg/mL, P = 0.006), waist circumference (84 ± 9 vs 93 ± 12 cm, P < 0.001), appendicular lean mass (ALM) (15.739 ± 2.129 vs 17.184 ± 2.104 kg, P = 0.001), and fat mass index (9.36 [7.29-11.43] vs 11.38 [9.95-15.33] kg/m 2 , P < 0.001) were lower in women with low bone mass by dual-energy x-ray absorptiometry. Univariate analysis showed that free estrogen index, time since menopause, SHBG, and fat mass were significant predictors of low bone mass, and ALM was a significant predictor against low bone mass. Appendicular lean mass persisted as an independent predictor against low bone mass in multivariate models with fat mass and SHBG. In turn, fat mass was no longer significant in this multivariate model after inclusion of SHBG. No association of FSH with low bone mass was observed.
Appendicular lean mass was a significant independent predictor against low bone mass in postmenopausal women. Further prospective studies are needed to investigate whether lean mass, fat mass, and FSH have a direct effect on bone mass in postmenopausal women, adding to the consequences of hypoestrogenism in this group.
本研究旨在探讨身体成分参数和激素水平作为绝经后女性低骨量（骨质减少/骨质疏松）的危险因素。
我们分析了139名无心血管疾病临床证据的绝经后女性的生物样本库样本。纳入标准为40岁以后绝经且在过去3个月内未使用激素治疗。采用双能X线吸收法评估骨密度和身体成分。测量所有参与者的性激素结合球蛋白（SHBG）和促卵泡生成素（FSH）水平。在57名参与者的子集中通过气相色谱/串联质谱法测量血清雌二醇。通过将雌二醇除以SHBG×100计算游离雌激素指数。
双能X线吸收法显示，低骨量女性的体重指数（25.0[22.5 - 26.5] vs 27.7[26.6 - 31.9]kg/m²，P < 0.001）、雌二醇（3.0[2.7 - 4.5] vs 6.0[2.7 - 15.0]pg/mL，P = 0.006）、腰围（84±9 vs 93±12 cm，P < 0.001）、四肢瘦体重（ALM）（15.739±2.129 vs 17.184±2.104 kg，P = 0.001）和脂肪量指数（9.36[7.29 - 11.43] vs 11.38[9.95 - 15.33]kg/m²，P < 0.001）较低。单因素分析显示，游离雌激素指数、绝经时间、SHBG和脂肪量是低骨量的显著预测因素，而ALM是低骨量的显著反向预测因素。在包含脂肪量和SHBG的多变量模型中，四肢瘦体重仍然是低骨量的独立反向预测因素。反过来，在纳入SHBG后，脂肪量在该多变量模型中不再显著。未观察到FSH与低骨量之间的关联。
四肢瘦体重是绝经后女性低骨量显著的独立反向预测因素。需要进一步的前瞻性研究来调查瘦体重、脂肪量和FSH是否对绝经后女性的骨量有直接影响，以及这对该群体雌激素缺乏的后果有何影响。
