【作者】 唐勇进；

【导师】 徐浩；

【作者基本信息】 暨南大学 ， 影像医学与核医学， 2012， 硕士

【摘要】 目的对13~19岁超重与正常体重青少年进行双能X线吸收法（DXA）骨密度和身体成分测量，分别比较其骨密度、身体成分和股骨近端骨强度指标的差异，探讨超重对青少年骨密度及股骨近端骨强度的影响。方法13~19岁健康男女青少年共139例，根据“中国学龄儿童青少年超重和肥胖筛查体重指数值分类标准”将其分为超重组(n=72，女29例，男43例)和正常体重组(n=67，女40例，男27例)，分别进行DXA骨密度（全身骨、腰椎L1-L4、股骨颈和全髋）、全身身体成分[全身骨量（WBBMC），lean mass（LM）和fat mass（FM)］测量，并采用髋关节强度分析（HSA）系统分析股骨近端截面惯性矩（CSMI）、截面面积（CSA）和截面模量（Z）等骨强度参数指标，分别比较不同性别青少年超重组与正常体重组骨密度及股骨近端骨强度的差异。结果1、超重男性和女性青少年的体重、体重指数（BMI）、身体成分参数（FM、LM、FM百分比）、WBBMC和BMD（全身骨、腰椎L1-L4、股骨颈和全髋）均高于正常体重组（P＜0.001）。经体重、BMI、FM和LM校正后，男女青少年超重组和正常体重组之间的WBBMC和BMD（全身、腰椎L1-L4、股骨颈和全髋）均无统计学差异（P＞0.05）。女性青少年的WBBMC和WBBMD与LM和FM呈正相关（r=0.533~0.784， P＜0.001），而男性青少年的WBBMC和WBBMD仅与LM呈正相关（r=0.438~0.699，P＜0.05），与FM无明显相关性。2、超重男女青少年的骨强度参数（CSA、CSMI和Z）均高于正常体重组（P＜0.05）；在进行体重、FM和LM较正后，超重女性青少年的骨强度参数（CSA、CSMI和Z）无统计学差异（P＞0.05），而男性经体重和LM较正后，其骨强度参数（CSA、CSMI和Z）无统计学差异（P＞0.05），而经FM校正后则有显著性差异（P＜0.05）。女性青少年骨强度参数（CSMI、CSA和Z）与LM和FM呈正相关（r=0.562~0.735，P＜0.05），而男性青少年骨强度参数（CSMI、CSA和Z）与LM呈正相关（r=0.673~0.729，P＜0.05），与FM无明显相关性。结论超重男女青少年的全身骨、腰椎和股骨近端骨密度高于正常体重组；超重男女青少年的股骨近端骨强度较高，可能与其对高LM产生动态负荷适应有关。更多还原

【Abstract】 ObjectiveThe aim of this study was to determine the influence of being overweight on bone mineraldensity(BMD)，and to compare hip bone strength indices in overweight adolescents andgender-matched normal weight controls using hip structural analysis (HSA).MethodsThis study included72overweight adolescents (29girls,43boys) and67gender-matchednormal weight controls (40girls,27boys). Whole body bone mineral area(WBBMA), wholebody bone mineral content (WBBMC)，whole body (WB)BMD, femoral neck (FN) BMD, totalhip(TH)BMD, lumbar spine (L1-L4)BMD and body composition (lean mass and fat mass) wereassessed by dual-energy X-ray absorptiometry (DXA). DXA HSA was performed using LunarenCORE, version10.5software. Structural parameters derived by HSA were the bonecross-sectional area (CSA)，the cross-sectional moment of inertia (CSMI) and the sectionmodulus (Z).Result①DXA measurements of weight, body mass index (BMI), LM, FM, FM%, WBBMC andBMD (WB, L1-L4, TH and FN) were higher in overweight adolescents compared togender-matched control（sP＜0.001）. After adjusting for weight, BMI, lean mass, fat mass, thesedifferences disappeared. Lean mass and fat mass were positively correlated to WBBMC andWBBMD for adolescent girls（r=0.533~0.784, P＜0.001）. Lean mass was positively correlatedto WBBMC and WBBMD（r=0.438~0.699, P＜0.05）, but fat mass was not related to WBBMCand WBBMD for adolescent boys.②CSA, CSMI, and Z of femoral neck were higher inoverweight adolescents compared to controls (P＜0.05). After adjustment for either body weightor lean mass, using a one-way analysis of covariance, there were no differences between the twogroups regarding the HSA variables (CSA, CSMI and Z). After adjusting for fat mass,overweight boys displayed higher values of CSA, CSMI and Z in comparison to controls (P＜ 0.05), but there were not signicant differences between overweight girls and controls. Lean massand fat mass were all positively correlated with all HSA parameters (CSMI, CSA and Z) foradolescent girls（r=0.562~0.735, P＜0.05）. Lean mass was positively correlated with all HSAparameters (CSMI, CSA and Z)（r=0.673~0.729, P＜0.05）, but fat mass was not positivelyrelated with all HSA parameters (CSMI, CSA and Z) for adolescent boys.ConclusionOverweight adolescents do have higher BMD when compared with controls. Overweightadolescents have greater indices of proximal femur bone geometry in comparison to controls atthe femoral neck. Proximal femur bone geometric strength in overweight adolescents wasappropriately adapted to lean mass.更多还原