Li Ran, Wen Zhi-Gang, Li Hai-Xia, Yu Qing, Xu Yang, Xiao Su-Mei
Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China.
Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, China; Department of Endocrinology, Jiangmen Central Hospital, Affiliated Jiangmen Hospital of Sun Yat-sen University, Jiangmen, Guangdong, China.
J Clin Densitom. 2020 Oct-Dec;23(4):588-595. doi: 10.1016/j.jocd.2020.01.001. Epub 2020 Jan 9.
This 2-year longitudinal study aimed to detect the associations of sex steroids, sex hormone-binding globulin with bone parameters and the changes thereof in Chinese male adolescents. A total of 642 male students aged 12-16 years from a secondary school in Jiangmen, China, were included. Total testosterone (T), total oestradiol (E2), and sex hormone-binding globulin were measured by chemiluminescence immunoassay. The bioavailable T (BioT) and E2 (BioE2) were calculated. The speed of sound, broadband ultrasound attenuation, and stiffness index of the right heel were measured by Sahara Clinical Bone Sonometer at both baseline and 2-year follow-up. The confounding effects of age, height, weight, pubertal stage, physical activity, energy-adjusted dietary calcium intake, and dietary vitamin D intake were adjusted. The baseline value of each bone parameter was also adjusted in the longitudinal analysis. Results showed that total T and BioT were positively associated with bone parameters and changes in them (β = 0.076-0.115, p < 0.05). A threshold effect of BioT on broadband ultrasound attenuation, stiffness index and their changes were also observed. Positive associations between BioT and bone mass gain were observed only in individuals with BioT levels <240.0 ng/dl (β = 0.088-0.131, p < 0.05). Moreover, total E2 or BioE2 were found to be inversely associated with speed of sound and its change (β = -0.109 to -0.077, p < 0.05). This study supported that in Chinese male adolescents, serum T was a positive predictor for bone formation with a threshold effect, and E2 could have influence on the changes in bone architecture during puberty. These findings may improve the understanding of the effects of sex steroids on the acceleration of bone formation in male adolescents and provide useful information for the prediction model establishment of peak bone mass.
这项为期两年的纵向研究旨在检测中国男性青少年中甾体激素、性激素结合球蛋白与骨参数之间的关联及其变化情况。研究纳入了来自中国江门一所中学的642名年龄在12至16岁的男学生。采用化学发光免疫分析法测定总睾酮（T）、总雌二醇（E2）和性激素结合球蛋白。计算生物可利用睾酮（BioT）和生物可利用雌二醇（BioE2）。在基线和随访2年时，使用Sahara临床骨超声仪测量右足跟的声速、宽带超声衰减和硬度指数。对年龄、身高、体重、青春期阶段、身体活动、能量调整后的膳食钙摄入量和膳食维生素D摄入量的混杂效应进行了校正。在纵向分析中，还对每个骨参数的基线值进行了校正。结果显示，总T和BioT与骨参数及其变化呈正相关（β=0.076-0.115，p<0.05）。还观察到BioT对宽带超声衰减、硬度指数及其变化的阈值效应。仅在BioT水平<240.0 ng/dl的个体中观察到BioT与骨量增加之间的正相关（β=0.088-0.131，p<0.05）。此外，发现总E2或BioE2与声速及其变化呈负相关（β=-0.109至-0.077，p<0.05）。本研究支持在中国男性青少年中，血清T是骨形成的阳性预测因子，具有阈值效应，而E2可能对青春期骨结构的变化有影响。这些发现可能有助于加深对甾体激素对男性青少年骨形成加速作用的理解，并为建立峰值骨量预测模型提供有用信息。
