Dietrich K N, Berger O G, Succop P A
Department of Environmental Health, University of Cincinnati College of Medicine, OH 45267-0056.
Pediatrics. 1993 Feb;91(2):301-7.
The relationship between asymptomatic lead exposure and subtle deficits in intellectual attainment has been relatively well established by modern studies. However, neuromotor performance has rarely been the focus of these investigations. It was postulated that motor developmental outcomes may be more sensitive indicators of lead's adverse effects on the central nervous system as they are probably less confounded with social factors than cognitive and academic outcomes. A comprehensive neuromotor assessment battery was administered to 245 six-year-old urban inner-city children enrolled in the Cincinnati Lead Study. These children have been followed since birth with quarterly assessments of blood lead concentrations, medical status, and neurobehavioral development. Prior to covariate adjustment, neonatal, but not prenatal blood lead levels were associated with poorer scores on assessments of bilateral coordination, upper-limb speed and dexterity, and a composite index of fine-motor coordination. Averaged postnatal blood lead levels were also associated with lower scores on the aforementioned subtests as well as a measure of visual-motor control. Following statistical adjustment for covariates, neonatal blood lead levels were associated with poorer performance on a measure of upper-limb speed and dexterity and the fine-motor composite. Postnatal blood lead levels remained significantly associated with poorer scores on measures of bilateral coordination, visual-motor control, upper-limb speed and dexterity, and the fine-motor composite. Low to moderate lead exposure is associated with moderate deficits in gross and especially fine-motor developmental status. Results of this study provide support for recent initiatives to reduce the exposure of children to sources of environmental lead.
现代研究已相对充分地证实了无症状铅暴露与智力发育细微缺陷之间的关系。然而，神经运动表现很少成为这些研究的重点。据推测，运动发育结果可能是铅对中枢神经系统产生不良影响的更敏感指标，因为与认知和学业结果相比，它们可能较少受到社会因素的干扰。对参加辛辛那提铅研究的245名六岁城市内城区儿童进行了全面的神经运动评估。自出生以来，这些儿童每季度都要接受血铅浓度、健康状况和神经行为发育的评估。在进行协变量调整之前，新生儿血铅水平（而非产前血铅水平）与双侧协调、上肢速度和灵活性评估以及精细运动协调综合指数得分较低有关。出生后平均血铅水平也与上述子测试得分较低以及视觉运动控制指标有关。在对协变量进行统计调整后，新生儿血铅水平与上肢速度和灵活性测量以及精细运动综合指标的较差表现有关。出生后血铅水平仍与双侧协调、视觉运动控制、上肢速度和灵活性测量以及精细运动综合指标的较差得分显著相关。低至中度铅暴露与总体尤其是精细运动发育状况的中度缺陷有关。本研究结果为近期减少儿童接触环境铅源的倡议提供了支持。
