血清廋素与男性骨密度、体脂的关系

目的:探讨血清瘦素(leptin)与男性骨密度(BMD)及体脂之间的关系.方法:用ELISA测定350例20～80岁健康男性血清瘦素浓度;采用DXA仪测定BMD(腰椎、髋部及全身)及体成分(体脂及瘦体质量);以10种回归数学模型分别拟合瘦素与年龄、体质量指数,体脂及各部位骨密度的关系,选择最优拟合曲线.结果:血清瘦素与年龄以S型曲线回归模型拟合程度最好,其决定系数(R2)最大(R2=0.104,P＜0.009);而与体质量、体指数以复合回归模型拟合程度最好(分别R2=0.296,P＜0.001;R2=0.304,P＜0.001;R2=0.22,P＜0.001).血清瘦素与总体脂,体脂百分比相关(R2=0.461,P＜0.001;R2=0.448,P＜0.001).血清瘦素与腰椎前后位、腰椎侧位、股骨颈、髋部总体BMD显著相关(分别R2=0.115,P=0.005;R2=0.102,P=0.007;R2=0.098,P=0.01;R2=0.112,P=0.002).逐步多重线性回归分析显示瘦素不是男性各部位骨密度的独立影响因素.结论:血清瘦素浓度与男性体脂显著相关,但不是中国男性各部位骨密度的独立预测因子.

Serum leptin with bone mineral densityand body fat mass in males

Objective To determine the relationship of serum leptin concentration and bone mineral density(BMD),body fat mass in males.Methods Plasma concentrations of leptin in 350 Chinese males,aged 20 to 80 years were measured with ELISA;BMD values at lumbar spine,hip and total body BMD,and body composition,including lean tissue mass(LTM)and fat tissue mass(FTM),were measured using dual-energy-X-ray absorptiometry(DXA).The relationship between changes in serum leptin concentration with age,body weight,body mass index,body fat mass,and BMD values at 5 skeletal sites was fit by 10 regression models,and the models giving the best fit were selected.Results The S regression model best described the changes in serum leptin level with age(R2=0.104,P<0.009),while the compound regression model best described the changes in serum leptin concentration with BMI and weight(R2=0.296,P<0.001;R2 =0.304,P<0.001).Leptin concentration was correlated with FTM(R2=0.448,P<0.001)and rate of body fat(R2=0.461,P<0.001).The serum leptin level was significantly correlated with BMD of multiple skeletal sites(R2 was 0.115 for anterior spine BMD,0.102 for lateral spine BMD,0.098 for femoral neck BMD,0.112 for total hip BMD,respectively).In a multivariate analysis,leptin concentration was not a significant predictor of BMD at any site.Conclusion Serum leptin concentration correlates with body fat mass and percentage of body fat,but is not a significant predictor of BMD at any site in Chinese males.