Effects of Iron and Zinc Supplementation on Neuropsychological and Educational Achievement in Lead-exposed School Children
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 602
- 试验地点
- 1
- 主要终点
- Blood lead concentration
研究概览
简要总结
Lead is negatively linked to nutritional status, behavior and cognition in children. Despite extensive knowledge of its toxicity and efforts to reduce exposure, lead continues to be a problem in developed and developing countries. When lead exposure is unavoidable due to its pervasive nature, effective means of protecting or disrupting that exposure need to be developed. Nutritional interventions are one such option. We conducted a 2x2 factorial, placebo-controlled trial of 6-month iron and zinc supplementation among lead-exposed children in Torreón, Mexico (altitude 1060 m). Nine schools were selected based on proximity to a lead smelter and first-graders were individually randomized to daily treatment with 30 mg iron, 30 mg zinc, both, or placebo. In addition to biochemical indicators, cognitive functions and behavior were evaluated at baseline, after the 6-month supplementation period, and again after another 6 months (without supplementation).
At baseline, 602 children ages 6.2-8.5 years were enrolled.
详细描述
We conducted a 2x2 factorial, placebo-controlled trial of 6-month iron and zinc supplementation among lead-exposed children in Torreón, Mexico (altitude 1060 m) to test the hypothesis that supplementation with iron, zinc or both will reduce blood lead concentrations of the children and improve their cognition and behavior. Nine schools were selected based on proximity to a lead smelter and first-graders were individually randomized to daily treatment with 30 mg iron, 30 mg zinc, both, or placebo. In addition to biochemical indicators (blood lead, serum ferritin, CRP, serum zinc, urinary arsenic concentrations), cognitive functions and behavior were measured. Assessments were conducted at three time points: at baseline, after the 6 month treatment, and again after another 6 months without treatment. At baseline, 602 children ages 6.2-8.5 years were enrolled.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Factorial
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 6 Years 至 8 Years（Child）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •1st grade child
排除标准
- •Blood lead concentration =>45 ug/dL
- •Hemoglobin concentration < 9 g/dL
研究组 & 干预措施
Placebo
Sugar tablet formulated to look like the experimental arms of the study. Given daily by mouth for 6 months.
干预措施: Placebo (Dietary Supplement)
Ferrous fumarate and zinc oxide
Tablet, formulated as ferrous fumarate 30 mg plus zinc oxide 30 mg. Given once daily by mouth for 6 months.
干预措施: Zinc oxide (Dietary Supplement)
Ferrous fumarate and zinc oxide
Tablet, formulated as ferrous fumarate 30 mg plus zinc oxide 30 mg. Given once daily by mouth for 6 months.
干预措施: Ferrous fumarate (Dietary Supplement)
Zinc oxide
Tablet formulated as zinc oxide, 30 mg. Given once daily by mouth for 6 months.
干预措施: Zinc oxide (Dietary Supplement)
Ferrous fumarate
Tablet formulated as ferrous fumarate, 30 mg. Given once daily for 6 months.
干预措施: Ferrous fumarate (Dietary Supplement)
结局指标
主要结局
Blood lead concentration
时间窗: 6-12 months
次要结局
- Anthropometric composite(6-12 months)
- Serum ferritin concentration(6-12 months)
- Serum zinc concentration(6-12 months)
- Hemoglobin concentration(6-12 months)
- Peabody Picture Vocabulary Test, Math achievement test, tests of attention and memory(6-12 months)
- Conners Behavior Rating Scales for parents and teachers(6-12 months)