Are brain volumes based on magnetic resonance imaging mediators of the associations of cumulative lead dose with cognitive function?
Are brain volumes based on magnetic resonance imaging mediators of the associations of cumulative lead dose with cognitive function?
复制标题
DOI：
10.1093/aje/kwm326
复制
发表时间：
2008-02-15
影响因子：
5
通讯作者：
Schwartz, Brian S.
中科院分区：
文献类型：
--
作者：
Caffo, Brian;Chen, Sining;Schwartz, Brian S.
作者使用横截面数据（2001-2003）来考虑过去职业铅暴露影响认知功能的途径。他们的动机是将累积铅剂量与脑容量、脑容量与认知功能以及铅剂量与认知功能联系起来的研究。据推测，与铅相关的大脑区域介导了铅剂量和认知功能之间的部分关系。数据来源于美国正在进行的一项针对513名前有机铅制造工人的研究。磁共振成像被用来进行一种新的分析，调查调解。通过使用配准的图像得出与认知功能和铅剂量相关的风险，并用于随后的中介分析。累积铅剂量与视觉结构、执行功能和眼手协调领域的不良功能相关。关于这些领域，有强有力的证据表明，体积调解铅的影响认知的视觉结构域和执行功能和眼手协调的适度量。还使用了第二种基于路径分析的方法。为了解决机会协会解释这些发现的可能性，进行了置换分析，其结果支持了中介推论。评价容积调节的方法可能在流行病学神经影像学环境中具有普遍适用性。
The authors used cross-sectional data (2001-2003) to consider the pathway through which past occupational lead exposure impacts cognitive function. They were motivated by studies linking cumulative lead dose with brain volumes, volumes with cognitive function, and lead dose with cognitive function. It was hypothesized that the brain regions associated with lead mediate a portion of the relation between lead dose and cognitive function. Data were derived from an ongoing US study of 513 former organolead manufacturing workers. Magnetic resonance imaging was used to perform a novel analysis to investigate mediation. Volumes associated with cognitive function and lead dose were derived by using registered images and were used in a subsequent mediation analysis. Cumulative lead dose was associated with adverse function in the visuo-construction, executive function, and eye-hand coordination domains. Regarding these domains, there was strong evidence of volumetric mediation of lead's effect on cognition in the visuo-construction domain and a moderate amount for executive function and eye-hand coordination. A second path-analysis-based approach was also used. To address the possibility that chance associations explained these findings, a permuted analysis was conducted, the results of which supported the mediation inferences. The approach to evaluating volumetric mediation may have general applicability in epidemiologic neuroimaging settings.