TREATMENT OF LEAD IN CHILDREN

TLC研究是一项多中心、随机、安慰剂对照、双盲临床试验，针对12-33月龄、基线血铅浓度在20 - 44微克/分升之间的儿童，使用药物琥珀酸盐进行铅螯合。研究的主要结果是在随机化三年后使用韦氏学前和初级智力量表通过全面偏差智商得分来测量发育状况。次要目标包括评价铅螯合对其他发育状态指标的影响，特别是神经心理发育测试（包括注意力和执行功能）；身高、体重和头围的变化，以及收缩压和舒张压水平的变化。此外，缺铁与中低水平铅中毒之间的相互作用也在探索中。该研究对费城、纽瓦克、辛辛那提和巴尔的摩四个临床中心的儿童进行了1:1的随机分组。治疗分配和主要实验室测量都是双盲的。CHOP的登记工作于1997年1月17日完成。共有165名儿童被随机分配到该地点。为了达到这一目标，大约有500名儿童接受了研究筛选。到目前为止，已有60名儿童完成了研究，99名仍在随访中，6名失去了随访。最后评估将于二零零零年一月完成。

The TLC study is a multi-center, randomized, placebo-controlled, double-blind clinical trial of lead chelation with the drug succimer for children 12-33 months of age with baseline blood lead concentrations between 20 and 44 ug/dl. The primary outcome of interest is developmental status as measured by full-scale devation IQ score using the Wechsler Preschool and Primary Scales of Intelligence three years after randomization. Secondary objectives include the evaluation of the effects of lead chelation on other measures of developmental status, particularly tests of neuro-psychological developmental (including attention and executive function); changes in height, weight and head circumference, and changes in systolic and diastolic blood pressure levels. In addition, the interactions between iron deficiency and low moderate level lead poisoning are being explored. The study involves 1:1 randomization of children at four clinical centers in Philadelphia, Newark, Cincinnati, and Baltimore. Both treatment assignments and lead laboratory measures are double-blinded. Enrollment at the CHOP site was completed on January 17, 1997. A total of 165 children were randomized at this site. To achieve this enrollment, approximately 500 children were screened for the study. To date, 60 children have completed the study, 99 remain in follow-up and 6 are lost to follow-up. Final assessments will be completed by January, 2000.