Wright Robert O, Tsaih Shirng Wern, Schwartz Joel, Spiro Avron, McDonald Karen, Weiss Scott T, Hu Howard
Division of Emergency Medicine, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA.
Epidemiology. 2003 Nov;14(6):713-8. doi: 10.1097/01.EDE.0000081988.85964.db.
Lead is neurotoxic; yet, whether cognitive decline in older persons is associated with lead exposure is unknown. We studied whether lead exposure biomarkers are associated with cognitive test scores, as well as the modifying effects of age on the lead-cognition relationship.
Lead exposure biomarkers and Mini-Mental Status Exam (MMSE) scores were measured among subjects in the Normative Aging Study. Multiple linear and logistic regression analyses were performed to examine the cross-sectional association of these 2 variables.
We found an odds ratio (OR) of 2.1 for MMSE <24 with an increase from the lowest to the highest quartile of patella lead levels (95% confidence interval [CI] = 1.1 to 4.1). From the lowest to the highest quartile of blood lead the OR for low MMSE was 3.4 (CI = 1.6 to 6.2). There was an interaction between lead biomarkers and age. Among subjects in the lowest quartile of patella lead levels, MMSE score decreased by 0.03 points per year (CI = -0.07 to 0.005), whereas in the highest quartile, MMSE score decreased by 0.13 points per year (CI = -0.19 to -0.07). Similar interactions were found between blood lead levels and age.
Increased levels of lead in bone and blood are inversely associated with cognitive performance among older men. Lead exposure might accelerate age-associated cognitive decline.
铅具有神经毒性；然而，老年人的认知能力下降是否与铅暴露有关尚不清楚。我们研究了铅暴露生物标志物是否与认知测试得分相关，以及年龄对铅与认知关系的调节作用。
在标准老化研究的受试者中测量铅暴露生物标志物和简易精神状态检查表（MMSE）得分。进行了多元线性和逻辑回归分析，以检验这两个变量的横断面关联。
我们发现，随着髌骨铅水平从最低四分位数增加到最高四分位数，MMSE<24的比值比（OR）为2.1（95%置信区间[CI]=1.1至4.1）。从血铅的最低四分位数到最高四分位数，低MMSE的OR为3.4（CI=1.6至6.2）。铅生物标志物与年龄之间存在相互作用。在髌骨铅水平最低四分位数的受试者中，MMSE得分每年下降0.03分（CI=-0.07至0.005），而在最高四分位数中，MMSE得分每年下降0.13分（CI=-0.19至-0.07）。在血铅水平和年龄之间也发现了类似的相互作用。
老年男性骨骼和血液中铅水平升高与认知能力呈负相关。铅暴露可能会加速与年龄相关的认知能力下降。
