尿双酚A与女性身体组成成分和骨密度的关系

Relationship of urinary bisphenol A with body composition and bone mineral density in women

目的研究健康妇女人群中尿双酚A（bisphenol A,BPA）与身体组成成分和骨密度的关系。方法选取279名上海地区健康妇女，以双能X线骨密度仪（DXA）测定腰椎L2-L4和股骨颈（FN）骨密度，以生物电阻法测定其脂肪含量（FM）和非脂肪组织含量（FFM），并进行血清雌二醇、瘦素、骨钙素、尿BPA和尿Ⅰ型胶原交联氨基末端肽（NTx）检测。对尿BPA、12-L4骨密度、FN骨密度与其他各指标行Pearson相关性分析和偏相关分析。对影响L2-L4骨密度和FN骨密度的各因素进行多元逐步回归分析。结果Pearson相关分析显示该人群尿BPA与FM（r=0．309，P〈0．01）、血清瘦素水平（r=0．232，P=0．01）显著正相关。校正年龄、年龄和体重指数（BMI）、年龄和FFM后，尿BPA和FM仍显著相关；校正年龄和FFM后，尿BPA与血清瘦素正相关，但校正FM后，这一关系消失。尿BPA和L2-L4骨密度、FN骨密度以及血清雌激素水平以及骨转换指标不相关。结论BPA暴露与女性脂肪含量正相关，继而血清瘦素升高、但不影响体内雌二醇水平和骨转换及骨密度。

Objective To evaluate the correlation between urinary bisphenol A （BPA） and bone mineral density （BMD） in healthy women in Shanghai. Methods A total of 279 healthy women aged 21 to 68 years were enrolled. BMD was measured by DXA, fat mass and fat-free mass with bioelectric impedance analysis. Serum estradiol, leptin, osteocalcin, urinary BPA, and NTx levels were tested. Pearson＇s correlation analysis and partial correlation analysis were applied in analysing the correlations between urinary BPA, L2-IA BMD, femoral neck （FN） BMD with other indices. Multivariate stepwise regression analysis was used to identify factors that affected L2-L4 BMD and FN BMD. Results Pearson＇s correlation analysis revealed that urinal7 BPA had a significant positive correlation with fat mass（ r=0. 309, P〈0.01 ） and serum leptin concentration（ r=0. 232, P=0.01 ）. Partial correlation analysis showed that urinary BPA still had a significant positive correlation with fat mass ＇after adjustment of age, age plus BMI, age plus fat-free mass ; BPA also had a significant positive correlation with serum leptin after adjustment of age and fat-free mass. However, the positive relationship of BPA and leptin was lost after the adjustment of fat mass. There were no correlation between urinary BPA exposure with L2-IA BMD, FN BMD, serum estradiol and bone biochemical markers. Conclusions BPA exposure has positive correlation with fat-mass accumulation leading to enhanced leptin secretion. But it has no effect on serum estradiol level and bone metabolism in women.