Department of Nutritional Sciences, University of Arizona, Tucson, Arizona, 85721, USA.
Departments of Medicine, University of Arizona, Tucson, AZ, 85721, USA.
Int J Obes (Lond). 2018 Jun;42(6):1185-1194. doi: 10.1038/s41366-018-0134-x. Epub 2018 Jun 11.
BACKGROUND/OBJECTIVE: Childhood obesity has been separately associated with cardiometabolic risk factors (CMRs) and increased risk of fracture. However, both augmented and compromised bone mass have been reported among overweight/obese children. Metabolic dysfunction, often co-existing with obesity, may explain the discrepancy in previous studies. The aim of this study was to examine whether the relationship between adiposity and dual-energy X-ray absorptiometry (DXA) derived bone mass differed in young girls with and without CMR(s).
SUBJECTS/METHODS: Whole-body bone and body composition measures by DXA and measures of CMR (fasting glucose, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), systolic and diastolic blood pressure, waist circumference (WC)) were obtained from 307, 9- to 12-year-old girls. Girls with 1 or ≥ 2 CMR(s) were considered to be at risk (vs. no CMR). Multiple linear regression was used to test the relationship of total fat mass with total body bone mineral content (BMC) after controlling for height, lean mass, CMR risk, and other potential confounders.
There was a significant interaction between CMR risk and total body fat mass. When girls were stratified by CMR group, all groups had a significant positive relationship between fat mass and BMC (p < 0.05), however, girls with ≥ 2 CMRs had a lower BMC for a given level of body fat. Total body fat was not significantly related to bone mineral density (p > 0.05).
Fat mass has a positive relationship with BMC even after controlling for lean mass. However, the positive relationship of fat mass with BMC may be attenuated if multiple CMRs are present.
背景/目的：儿童肥胖症与心血管代谢风险因素（CMRs）和骨折风险增加分别相关。然而，超重/肥胖儿童的骨量增加和减少都有报道。常与肥胖并存的代谢功能障碍可能解释了先前研究中的差异。本研究旨在检查在有和无 CMR 的年轻女孩中，肥胖与双能 X 射线吸收法（DXA）测定的骨量之间的关系是否不同。
受试者/方法：从 307 名 9-12 岁女孩中获得 DXA 的全身骨和身体成分测量值以及 CMR（空腹血糖、高密度脂蛋白胆固醇（HDL-C）、甘油三酯（TG）、收缩压和舒张压、腰围（WC））。有 1 项或≥2 项 CMR 的女孩被认为有风险（vs. 无 CMR）。在控制身高、瘦体重、CMR 风险和其他潜在混杂因素后，使用多元线性回归检验总脂肪量与全身骨矿物质含量（BMC）的关系。
CMR 风险与全身脂肪量之间存在显著的交互作用。当按 CMR 组对女孩进行分层时，所有组的脂肪量与 BMC 之间都存在显著的正相关（p<0.05），但有≥2 项 CMR 的女孩的 BMC 与给定水平的体脂相关较低。全身脂肪量与骨矿物质密度无显著相关性（p>0.05）。
即使在控制瘦体重后，脂肪量与 BMC 仍呈正相关。然而，如果存在多个 CMR，则脂肪量与 BMC 的正相关可能会减弱。
