Impact of household air pollution (HAP) in-utero through early childhood on neurocognitive development from infancy to 8 years (HAPCOG Study)

摘要 在世界各地，93%的15岁以下儿童每天呼吸有毒空气，这会使他们的健康和 发展面临风险。在每年700万可归因于空气污染的死亡中，超过60%是由于接触到 家庭能源需求中燃烧生物质燃料或煤油造成的家庭空气污染(HAP)。这类燃料 燃烧效率低下，产生有毒污染物，如细颗粒物(PM2.5)和黑碳(BC)。母亲们 儿童遭受的接触最多，导致呼吸系统、心血管和神经损伤。风险 对孩子来说是从宫内开始的。孕妇吸入受污染的空气，对其发育中的胎儿和 新生儿，包括生长受限、早产和低出生体重。越来越多的证据表明 HAP会损害婴儿和儿童的神经认知发育。脑组织中的颗粒物沉积 已经证明；此外，HAP是一种接触重金属的媒介。高暴露可能会导致 氧化应激和全身炎症。有证据表明有中介因素：母亲的压力水平， 母婴营养状况和家庭环境。我们将探讨接触HAP对儿童的影响 神经认知发展，评估已知中介因素的影响。我们的研究充分利用了 最近在尼日利亚进行的一项随机对照试验(RCT)带来了一个独特的机会。我们随机选择了324名 孕妇根据燃料使用情况进行分组：清洁与污染。污染燃料用户显示：1) 早产增加、流产和分娩时胎龄降低，2)胎盘的生物标志物 缺氧，3)胎盘血管过度形成，4)增加全身炎症。我们进一步 研究发现，污染燃料使用者在怀孕期间报告的心理社会压力更大，精力更少。我们有 继续跟踪RCT儿童(发现队列)，监测他们接触HAP的情况。我们现在求婚 检验出生前和出生后大量暴露于HAP会对神经认知产生负面影响的假设 发展。我们将评估我们的发现队列和额外的验证队列的发展 来自一组新的怀孕(晚期妊娠)妇女的新生儿。我们将监测个人接触HAP的情况 母亲和孩子，评估炎症和氧化应激的生物标记物以及血液中 微量营养素和重金属。我们的目标是评估从婴儿期到8岁的神经认知发展。 与以下因素有关：(1)产前和儿童早期HAP暴露；(2)母亲心理社会压力水平， 母婴营养状况，以及儿童的家庭环境。影响：结果将阐明HAP如何 暴露和母亲的压力影响儿童的神经认知发育，为减少HAP的政策提供信息 通过推广使用清洁燃料炉灶的项目。我们将发展适应语言/文化的能力 对儿童神经认知的评估--撒哈拉以南非洲地区非常需要--并建立试点绩效 规范。这将为尼日利亚今后开展更多此类研究建立能力。

ABSTRACT Around the world, 93% of children under age 15 breathe toxic air every day that puts their health and development at risk. Of 7 million deaths per year attributable to air pollution, over 60% are due to exposure to household air pollution (HAP) from burning biomass fuels or kerosene for household energy needs. Such fuels burn inefficiently, producing toxic pollutants like fine particulate matter (PM2.5) and black carbon (BC). Mothers and children suffer the highest exposures, resulting in respiratory, cardiovascular, and neurologic injury. Risks to children begin in-utero. Pregnant women inhale polluted air, with ill effects on their developing fetuses and newborns, including growth restriction, preterm birth, and low birth weight. Mounting evidence suggests that HAP can impair infant and child neurocognitive development. Particulate matter deposits in brain tissue have been demonstrated; also, HAP is a medium of exposure to heavy metals. High exposures likely induce oxidative stress and systemic inflammation. There is evidence of mediating factors: maternal stress level, mother/child nutritional status, and home environment. We will explore the impact of HAP exposures on child neurocognitive development, assessing the influence of known mediating factors. Our research capitalizes on a unique opportunity flowing from a recent randomized controlled trial (RCT) in Nigeria. We randomized 324 pregnant women into groups based on fuel use: clean versus polluting. Polluting-fuel users showed: 1) increased preterm delivery, miscarriage, and reduced gestational age at delivery, 2) biomarkers of placental oxygen deprivation, 3) excessive placental vascularization, and 4) increased systemic inflammation. We further found that polluting-fuel users reported more psychosocial stress and less energy during pregnancy. We have continued to follow the RCT children (DISCOVERY COHORT), monitoring their HAP exposures. We propose now to test the hypothesis that high pre- and postnatal HAP exposure negatively impacts neurocognitive development. We will assess development in our DISCOVERY COHORT and an added VALIDATION COHORT of newborns from a new group of pregnant (3rd trimester) women. We will monitor personal HAP exposures of mothers and children, assessing biomarkers of inflammation and oxidative stress and blood levels of micronutrients and heavy metals. We aim to assess neurocognitive development from infancy to age 8 years as associated with: (1) prenatal and early childhood HAP exposures; (2) maternal psychosocial stress level, maternal and child nutritional status, and child's home environment. Impact: Results will illuminate how HAP exposures and maternal stress affect child neurocognitive development, informing policies to reduce HAP through programs that promote use of clean-fuel cookstoves. We will develop language/culturally-adapted assessments of child neurocognition—much needed in sub-Saharan Africa—and establish pilot performance norms. This will build capacity for more research of this kind in Nigeria in the future.