Medical Research Council Centre for Causal Analyses in Translational Epidemiology, School of Social and Community Medicine, University of Bristol, Oakfield House, Oakfield Grove BS8 2BN, United Kingdom.
J Clin Endocrinol Metab. 2012 Jun;97(6):2068-76. doi: 10.1210/jc.2011-2721. Epub 2012 Apr 6.
It is unclear whether variation in insulin resistance mediates the positive association of fat mass with bone mass in children/adolescents.
Our objective was to examine whether markers linked to insulin resistance [fasting insulin, glucose, triglycerides, and high-density lipoprotein cholesterol (HDLc)] are associated with bone mass in adolescents, and if they are, to examine whether they mediate the fat mass-bone mass association.
We conducted a cross-sectional analysis in participants from the Avon Longitudinal Study of Parents and Children.
Participants included 2305 (1100 male) individuals of mean age 15.5 yr.
We evaluated total body less head bone mineral content (BMC) (grams), bone area (BA) (square centimeters), and bone mineral density (BMD) (grams per square centimeter) from a dual-energy x-ray absorptiometry scan.
Fat mass, fasting insulin, and triglycerides were positively associated with BMD, BMC, and BA; HDLc was inversely associated with these outcomes. For example, the adjusted mean difference in BMC per 1 sd fasting insulin was 45 g (95% confidence interval = 17-73 g) in males and 50 g (95% confidence interval = 28-72 g) in females. When the associations of fat mass with outcomes were adjusted for markers of insulin resistance, they were largely unchanged. Associations of triglycerides and HDLc with outcomes were attenuated to the null when they were adjusted for fat mass, whereas those of insulin changed direction; i.e. with adjustment for fat mass, higher fasting insulin was associated with lower BMD, BMC, and BA.
Fasting insulin, glucose, and lipids do not appear to mediate the positive association of fat mass with bone mass in children/adolescents. The inverse association of fasting insulin with BMD, BMC, and BA once fat mass has been controlled for needs further study.
目前尚不清楚胰岛素抵抗的变化是否会介导脂肪量与儿童/青少年骨量之间的正相关。
我们的目的是研究与胰岛素抵抗相关的标志物（空腹胰岛素、血糖、甘油三酯和高密度脂蛋白胆固醇（HDLc））是否与青少年的骨量相关，以及如果相关，是否可以介导脂肪量与骨量的相关性。
我们在阿冯纵向研究父母和儿童的参与者中进行了横断面分析。
参与者包括 2305 名（男性 1100 名）平均年龄为 15.5 岁的个体。
体脂量、空腹胰岛素和甘油三酯与 BMD、BMC 和 BA 呈正相关；HDLc 与这些结果呈负相关。例如，在男性中，空腹胰岛素每增加 1 个标准差，BMC 的平均差异为 45g（95%置信区间= 17-73g），在女性中为 50g（95%置信区间= 28-72g）。当将胰岛素抵抗标志物与结局的关联进行调整时，体脂量与结局的关联基本保持不变。当将甘油三酯和 HDLc 与结局的关联调整为脂肪量时，这些关联的作用减弱到零，而胰岛素的关联则发生变化；即当调整脂肪量时，空腹胰岛素越高，BMD、BMC 和 BA 越低。
空腹胰岛素、葡萄糖和脂质似乎不能介导脂肪量与儿童/青少年骨量之间的正相关。一旦控制了脂肪量，空腹胰岛素与 BMD、BMC 和 BA 的负相关关系需要进一步研究。
