Xu Yingying, Khoury Jane C, Sucharew Heidi, Dietrich Kim, Yolton Kimberly
Cincinnati Children's Hospital Medical Center, Department of Pediatrics, Division of General and Community Pediatrics, Cincinnati, OH, United States.
Cincinnati Children's Hospital Medical Center, Department of Pediatrics, Division of Biostatistics and Epidemiology, Cincinnati, OH, United States.
Neurotoxicol Teratol. 2016 Mar-Apr;54:61-7. doi: 10.1016/j.ntt.2016.02.002. Epub 2016 Feb 12.
Studies examining the effects of low-level gestational methylmercury exposure from fish consumption on infant neurobehavioral outcomes in the offspring are limited and inconclusive. Our objective was to examine the effects of low-level gestational exposure to methylmercury on neurobehavioral outcomes in early infancy.
We assessed neurobehavior of 344 infants at 5-weeks using the NICU Network Neurobehavioral Scale (NNNS). Gestational mercury exposure was measured as whole blood total mercury (WBTHg) in maternal and cord blood. We collected fish consumption information and estimated polyunsaturated fatty acid (PUFA) intake. We examined the association between gestational mercury exposure and NNNS scales using regression, adjusting for covariates.
Geometric mean of maternal and cord WBTHg were 0.64 and 0.72 μg/L, respectively. Most mothers (84%) reported eating fish during pregnancy. Infants with higher prenatal mercury exposure showed increased asymmetric reflexes among girls (p=0.04 for maternal WBTHg and p=0.03 for cord WBTHg), less need for special handling during the assessment (p=0.03 for cord WBTHg) and a trend of better attention (p=0.054 for both maternal WBTHg and cord WBTHg). Similarly, infants born to mothers with higher fish consumption or estimated PUFA intake also had increased asymmetric reflexes and less need for special handling. In models simultaneously adjusted for WBTHg and fish consumption (or PUFA intake), the previously observed WBTHg effects were attenuated; and higher fish consumption (or PUFA intake) was significantly associated with less need for special handling.
In a cohort with low level mercury exposure and reporting low fish consumption, we found minimal evidence of mercury associated detrimental effects on neurobehavioral outcomes during early infancy. Higher prenatal mercury exposure was associated with more frequent asymmetric reflexes in girls. In contrast, infants with higher prenatal mercury exposure and those whose mothers consumed more fish had better attention and needed less special handling, which likely reflect the beneficial nutritional effects of fish consumption.
关于孕期食用鱼类导致低水平甲基汞暴露对后代婴儿神经行为结局影响的研究有限且尚无定论。我们的目标是研究孕期低水平甲基汞暴露对婴儿早期神经行为结局的影响。
我们使用新生儿重症监护病房网络神经行为量表（NNNS）在婴儿5周龄时评估了344名婴儿的神经行为。孕期汞暴露通过母亲和脐带血中的全血总汞（WBTHg）来衡量。我们收集了鱼类食用信息并估算了多不饱和脂肪酸（PUFA）摄入量。我们使用回归分析，对协变量进行调整，研究孕期汞暴露与NNNS量表之间的关联。
母亲和脐带血WBTHg的几何平均值分别为0.64和0.72μg/L。大多数母亲（84%）报告在孕期食用鱼类。产前汞暴露较高的婴儿中，女孩的不对称反射增加（母亲WBTHg的p值为0.04，脐带血WBTHg的p值为0.03），评估期间对特殊护理的需求减少（脐带血WBTHg的p值为0.03），且有注意力更好的趋势（母亲和脐带血WBTHg的p值均为0.054）。同样，母亲鱼类食用量或估算的PUFA摄入量较高的婴儿也有更多的不对称反射，对特殊护理的需求也较少。在同时对WBTHg和鱼类食用量（或PUFA摄入量）进行调整的模型中，之前观察到的WBTHg效应减弱；较高的鱼类食用量（或PUFA摄入量）与对特殊护理需求较少显著相关。
在一个汞暴露水平低且鱼类食用量报告也低的队列中，我们发现几乎没有证据表明汞对婴儿早期神经行为结局有有害影响。产前汞暴露较高与女孩更频繁的不对称反射有关。相反，产前汞暴露较高的婴儿以及母亲食用鱼类较多的婴儿注意力更好，对特殊护理的需求较少，这可能反映了食用鱼类的有益营养作用。
