Table_2_Association of Sex Hormones and Sex Hormone-Binding Globulin Levels With Bone Mineral Density in Adolescents Aged 12–19 Years.xls

BackgroundSex hormones are recognized to play a significant role in increasing bone mineral density (BMD) and promoting bone maturation during adolescence. The purpose of our study was to use a database with large population data to evaluate the association of BMD with sex hormones (including testosterone and estradiol) and sex hormone-binding globulin (SHBG) in adolescent boys and girls aged 12–19 years.MethodsThe data for our study were taken from the National Health and Nutrition Examination Survey 2013-2016, and we used weighted multiple linear regression models to assess the relationship between testosterone, estradiol, and SHBG and total BMD. We use weighted generalized additive models and smooth curve fitting to discover underlying nonlinear relationships.ResultsA total of 1648 teenagers (853 boys, 795 girls) were selected for the final analysis. In boys, testosterone and estradiol levels were positively associated with total BMD, whereas SHBG levels were negatively associated with total BMD after adjusting for covariates [P < 0.05; 95% confidence interval (CI)]. In addition, there was a point between estradiol and total BMD, after which the positive correlation between estradiol and total BMD was relatively insignificant in boys. In girls, there was a positive association between estradiol and total BMD (P < 0.05; 95% CI), but there was no significant association between the testosterone (β 0.0004; 95% CI -0.0001 to 0.0008) or SHBG (β -0.0001; 95% CI -0.0002 to 0.0001) levels and total BMD. We also found an inverted U-shaped association between testosterone and total BMD with the inflection point at 25.4 ng/dL of testosterone.ConclusionsWe found differences in the association of sex hormones with total BMD in boys and girls. Based on our findings, an appropriate increase in serum testosterone levels may be beneficial for skeletal development in girls because of the inverted U-shaped relationship (with the inflection point at 25.4 ng/dL of testosterone), and a high testosterone level might be detrimental to BMD. Furthermore, keeping estradiol levels below a certain level in boys (24.3 pg/mL) may be considered.

背景性激素在增进骨矿物质密度（BMD）及促进青春期骨骼成熟方面发挥着至关重要的作用。本研究旨在利用包含大规模人群数据的数据库，评估12至19岁青少年男女中骨矿物质密度（BMD）与性激素（包括睾酮和雌二醇）以及性激素结合球蛋白（SHBG）之间的关联。方法本研究数据来源于2013-2016年国家健康与营养调查，我们采用加权多元线性回归模型来评估睾酮、雌二醇和SHBG与总BMD之间的关系。我们采用加权广义加性模型和光滑曲线拟合来揭示潜在的非线性关系。结果共选取1648名青少年（853名男孩，795名女孩）进行最终分析。在男孩中，调整协变量后，睾酮和雌二醇水平与总BMD呈正相关，而SHBG水平与总BMD呈负相关[P < 0.05；95%置信区间（CI）]。此外，在雌二醇和总BMD之间存在一个转折点，在此之后，雌二醇与总BMD之间的正相关在男孩中相对不显著。在女孩中，雌二醇与总BMD之间存在正相关（P < 0.05；95%置信区间），但睾酮（β 0.0004；95%置信区间 -0.0001至0.0008）或SHBG（β -0.0001；95%置信区间 -0.0002至0.0001）水平与总BMD之间没有显著关联。我们还发现，睾酮与总BMD之间存在倒U形关联，其拐点为25.4 ng/dL的睾酮水平。结论研究发现，男孩和女孩中性激素与总BMD的关联存在差异。基于我们的研究结果，由于存在倒U形关系（拐点为睾酮25.4 ng/dL），血清睾酮水平的适当增加可能对女孩的骨骼发育有益，而高睾酮水平可能对BMD有害。此外，考虑将男孩的雌二醇水平保持在一定水平以下（24.3 pg/mL）可能是有益的。