Taylor Caroline M, Humphriss Rachel, Hall Amanda, Golding Jean, Emond Alan M
Centre for Child and Adolescent Health, School of Social and Community Medicine, University of Bristol, Bristol, UK.
School of Social and Community Medicine, University of Bristol, Bristol, UK Children's Hearing Centre, University Bristol NHS Foundation Trust, Bristol, UK.
BMJ Open. 2015 Dec 30;5(12):e009635. doi: 10.1136/bmjopen-2015-009635.
Most studies reporting evidence of adverse effects of lead and cadmium on the ability to balance have been conducted in high-exposure groups or have included adults. The effects of prenatal exposure have not been well studied, nor have the effects in children been directly studied. The aim of the study was to identify the associations of lead (in utero and in childhood) and cadmium (in utero) exposure with the ability to balance in children aged 7 and 10 years.
Prospective birth cohort study.
Maternal blood lead (n=4285) and cadmium (n=4286) levels were measured by inductively coupled plasma mass spectrometry in women enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) during pregnancy. Child lead levels were measured in a subsample of 582 of ALSPAC children at age 30 months.
Children completed a heel-to-toe walking test at 7 years. At 10 years, the children underwent clinical tests of static and dynamic balance. Statistical analysis using SPSS V.19 included logistic regression modelling, comparing categories of ≥ 5 vs <5 µg/dL for lead, and ≥ 1 vs <1 µg/L for cadmium.
Balance at age 7 years was not associated with elevated in utero lead or cadmium exposure (adjusted OR for balance dysfunction: Pb 1.01 (95% CI 0.95 to 1.01), n=1732; Cd 0.95 (0.77 to 1.20), n=1734), or with elevated child blood lead level at age 30 months (adjusted OR 0.98 (0.92 to 1.05), n=354). Similarly, neither measures of static nor dynamic balance at age 10 years were associated with in utero lead or cadmium exposure, or child lead level.
These findings do not provide any evidence of an association of prenatal exposure to lead or cadmium, or lead levels in childhood, on balance ability in children. Confirmation in other cohorts is needed.
大多数报告铅和镉对平衡能力产生不良影响证据的研究是在高暴露组中进行的，或者纳入了成年人。产前暴露的影响尚未得到充分研究，儿童的影响也未得到直接研究。本研究的目的是确定（子宫内和儿童期的）铅暴露以及（子宫内的）镉暴露与7岁和10岁儿童平衡能力之间的关联。
前瞻性出生队列研究。
在孕期参加雅芳亲子纵向研究（ALSPAC）的女性中，通过电感耦合等离子体质谱法测量母体血铅（n = 4285）和血镉（n = 4286）水平。在ALSPAC队列中抽取582名儿童，于30个月大时测量其血铅水平。
儿童在7岁时完成足跟到足尖行走测试。在10岁时，儿童接受静态和动态平衡的临床测试。使用SPSS V.19进行统计分析，包括逻辑回归建模，比较铅水平≥5与<5μg/dL、镉水平≥1与<1μg/L的类别。
7岁时的平衡能力与子宫内铅或镉暴露升高无关（平衡功能障碍的校正比值比：铅1.01（95%可信区间0.95至1.01），n = 1732；镉0.95（0.77至1.20），n = 1734），也与30个月大时儿童血铅水平升高无关（校正比值比0.98（0.92至1.05），n = 354）。同样，10岁时的静态或动态平衡测量指标均与子宫内铅或镉暴露以及儿童血铅水平无关。
这些发现未提供任何证据表明产前铅或镉暴露或儿童期铅水平与儿童平衡能力之间存在关联。需要在其他队列中进行验证。
