Bhattacharya A, Shukla R, Bornschein R, Dietrich K, Kopke J E
Department of Environmental Health, University of Cincinnati, Medical School, Ohio 45267.
Neurotoxicology. 1988 Fall;9(3):327-40.
Previous studies reported that some children who survive acute lead encephalopathy suffer from ataxia and have difficulties maintaining postural equilibrium. More recent studies have failed to quantify postural imbalance in association with lower levels of lead exposures, perhaps due to the insensitivity of the clinical measure. In our study, we noninvasively measured postural disequilibrium with a microprocessor-based force platform. The test provides a real time quantification of the body's center of gravity movement pattern. Measurements were made in a cohort of 33 inner city children (mean age: six years +/- 0.4 SD) with well documented blood lead histories. The average maximum blood lead of these children during their first six years of life was 23.5 micrograms/dl (range = 8.5 to 49.4). The children performed four postural tests [i.e., standing eyes open (EO) and closed (EC), on firm surface and standing on a compliant foam surface with eyes open (FO) and closed (FC)]. The results indicated that the maximum blood lead incurred during the second year of life was significantly positively related to postural sway, and the body balance was most affected in the EC test where visual cues were eliminated and proprioceptive feedback was not modified. Fetal Pb exposure levels as well as Pb exposures during the first year of life were not correlated with postural sway of six year olds. However, the maximum blood lead concentration beyond two years of life was significantly associated with the postural sway at six years of age.
先前的研究报告称，一些急性铅中毒性脑病幸存的儿童患有共济失调，难以维持姿势平衡。最近的研究未能对较低铅暴露水平与姿势失衡进行量化，这可能是由于临床测量方法不够灵敏。在我们的研究中，我们使用基于微处理器的测力平台对姿势失衡进行了无创测量。该测试可实时量化身体重心的运动模式。我们对33名市中心儿童（平均年龄：6岁±0.4标准差）进行了测量，这些儿童都有详细记录的血铅病史。这些儿童在生命的前六年中，平均最大血铅水平为23.5微克/分升（范围为8.5至49.4）。孩子们进行了四项姿势测试[即睁眼（EO）和闭眼（EC）站立，在坚实表面上以及在柔软泡沫表面上睁眼（FO）和闭眼（FC）站立]。结果表明，生命第二年期间的最大血铅水平与姿势摆动呈显著正相关，在消除视觉线索且本体感觉反馈未改变的EC测试中，身体平衡受影响最大。胎儿期铅暴露水平以及生命第一年的铅暴露与6岁儿童的姿势摆动无关。然而，两岁以后的最大血铅浓度与6岁时的姿势摆动显著相关。
