Mother-child hemoglobin at preconception and first 1000 days and child development at 6 years

贫血是一个重要的全球性健康问题。对截止值有效性的关切 WHO于1968年发布血红蛋白（Hb）标准已被提高。一些系统性综述，包括最近的 Young博士（PI）的一项研究显示，关于贫血与糖尿病之间关系的数据缺乏，证据不足。 功能性后果，特别是儿童健康和发育（CHD）。世卫组织已发出分析呼吁 这可以告知其截断值对于各种结果（包括CHD）的适当性。我们有一个 独特的机会，以检查产妇和儿童之间的关系血红蛋白测量整个 孕前、怀孕和幼儿期的连续性以及一系列CHD指标。数据我们将 使用来自一项随机、双盲、安慰剂对照的孕前微量营养素试验 补充剂（NCT 01665378; PRECONCEPT研究; PI：Ramakrishnan）。 从孕前（n=5011名妇女）到1599名妇女的怀孕和分娩， 活产，以及从出生到6岁的1 290名儿童。为了评估母亲/儿童Hb的时间特异性影响，有效 需要统计方法来产生Hb随时间变化的不相关估计。我们将应用 创新的条件建模方法来回答以下问题。1.母亲是否有偏见 从出生到6岁与CHD相关的Hb浓度？母体孕前Hb 浓度将与CHD结局呈正相关[1]。出生尺寸，2. 3、12和24个月时的Hb，3. 运动和智力发育（Bayley量表用于12和24个月时的婴儿发育，Wechsler量表用于 6岁时的整体智力、表现和语言得分）。2：时间变化的作用， 从孕前到分娩的母体Hb与CHD的关系？母体血红蛋白对冠心病的相对重要性 将在四个时期变化：孕前，孕前-第一个三个月，第一-第二个三个三个月和第二-第三个月。 3：儿童血红蛋白变化的时间在生命的前2年对儿童认知的作用是什么？ 6岁？儿童血红蛋白对认知的相对重要性在三个时期会有所不同：3个月，3个月-1岁，1岁-2岁。 这项拟议中的研究将填补目前关于孕产妇和新生儿之间关系的知识空白。 出生前和出生后1000天内的儿童血红蛋白以及6岁以下儿童的认知功能。 重要的优势包括可获得大量母子配对样本的前瞻性、高质量数据 从先入之见到6岁，创新的统计方法和高素质的应用 团队包括来自Emory的初级（PI：年轻，早期研究者）和经验丰富的高级研究者 越南阮泰医药大学。

Anemia is an important global health problem. Concerns about the validity of the cut-off values for hemoglobin (Hb) that WHO issued in 1968 have been raised. Several systematic reviews, including a recent one by Dr. Young (PI), reveal a paucity of data and insufficient evidence on relationships between anemia and functional consequences, especially child health and development (CHD). WHO has issued a call for analyses that can inform the appropriateness of its cut-off values for a variety of outcomes, including CHD. We have a unique opportunity to examine the relationships between maternal and child Hb measured across the continuum of preconception, pregnancy and early childhood and a battery of CHD measures. The data we will use are from a randomized, double-blinded, placebo-controlled trial of preconceptional micronutrient supplementation (NCT01665378; PRECONCEPT study; PI: Ramakrishnan) conducted in Vietnam. Prospective data are available from preconception (n=5011 women), through pregnancy and delivery for 1599 livebirths, and from birth to 6 y for 1290 children. To assess timing-specific influences of mother/child Hb, valid statistical methods are needed to generate uncorrelated estimates of Hb changes over time. We will apply innovative conditional modeling methods to answer the following questions. 1: Are maternal preconception Hb concentrations associated with CHD from birth through age 6y? Maternal preconception Hb concentrations will be positively associated with CHD outcomes [1. birth size, 2. Hb at 3, 12 and 24 mo, 3. motor and mental development (Bayley scales for infant development at 12 and 24 mo, and Wechsler scale for global intelligence, performance and verbal scores at 6y). 2: What is the role of timing of changes in maternal Hb across preconception to delivery on CHD? The relative importance of maternal Hb for CHD will vary across four periods: preconception, preconception - trimester 1, trimester 1 - 2, and trimester 2 - 3. 3: What is the role of timing of child Hb changes across the first 2 years of life on child cognition at 6y? The relative importance of child Hb on cognition will vary across three periods: 3mo, 3mo - 1y, and 1y - 2y. The proposed research will fill important gaps in current knowledge about relationships between maternal and child Hb before and during the 1st 1000 days of life and child cognitive functioning through the age of 6 years. Important strengths include availability of prospective, high quality data on a large sample of mother-child pairs from preconception through age 6 y, the application of innovative statistical methods and a highly qualified team that includes junior (PI: Young, early stage investigator) and senior experienced investigators from Emory University and Thai Nguyen University of Medicine and Pharmacy in Vietnam.