DHA in Pregnancy and Immune Function in Mexican Infants

描述(申请人提供)：我们正在墨西哥库埃纳瓦卡的孕妇中进行一项随机、双盲对照试验，以研究在分娩前每天补充200毫克二十二碳六烯酸(DHA)对a)分娩结局的影响b)母亲血液和母乳中的DMA水平c)出生后的生长发育和d)婴儿的DHA状态。这是国际卫生系、埃默里大学和墨西哥国家公共卫生研究所共同努力的成果。本补充研究的重点是评价补充DHA对婴儿免疫功能的影响。我们将分析目前作为父母研究方案的一部分收集的婴儿血浆和母亲母乳样本。DHA和其他n-3多不饱和脂肪酸已被证明可以调节人类的免疫功能；然而，很少有研究涉及DHA的独立作用。补充研究的中心假设是，孕妇在怀孕期间补充DHA将调节婴儿的免疫功能，这一假设将通过测量婴儿免疫功能的指标来检验，包括在出生时(脐带血)和3个月时测量血浆中总免疫球蛋白(Ig)浓度和免疫球蛋白亚类浓度。在常规接种1剂白喉疫苗后，将在3个月时检测婴儿的抗原特异性抗体应答。我们将在产后1个月和3个月检测母乳中的IgA浓度。家长研究确定的样本量为每组116对母子。位于亚特兰大的疾病控制中心将免费进行免疫学评估。数据分析将包括确保随机化有效性后的组比较(意向治疗)。如果需要对潜在混杂因素进行控制，将进行调整后的比较(使用协方差分析)。据我们所知，目前还没有研究评估孕妇孕期补充DHA对婴儿免疫功能的影响。

DESCRIPTION (provided by applicant): We are conducting a randomized, double-blinded controlled trial among pregnant women in Cuernavaca, Mexico, to study the effect of daily supplementation with 200 mg docosahexaenoic acid (DHA) until delivery on a) birth outcomes b) maternal blood and breast milk DMA levels c) postnatal growth and development and d) infant DHA status. This is a collaborative effort among the Department of International Health, Emory University, and the Institute Nacional de Salud Publica in Mexico. The focus of this supplemental study is to evaluate the effect of DHA supplementation on infant immune function. We will analyze infant plasma and maternal breast milk samples currently being collected as part of the parent study protocol. DHA and other n-3 polyunsaturated fatty acids have been shown to modulate immune function in humans; however, few studies have addressed the independent effect of DHA. The central hypothesis of the supplemental study, that maternal DHA supplementation in pregnancy will modulate infant immune function, will be tested by measuring indicators of infant immune function including total immunoglobulin (Ig) concentrations and IgG sub-class concentrations in plasma, to be measured at birth (cord blood) and at 3 months. Antigen-specific antibody response after routine vaccination with 1 dose of diphtheria vaccine will be measured in infants at 3 months. We will measure breast milk IgA concentrations at 1 and 3 months post-partum. The sample size fixed by the parent study will be 116 mother-child pairs per group. The immunological assessments will be done at no cost to the study by the Centers for Disease Control, Atlanta. Data analysis will include group comparisons (intent-to-treat) after ensuring effectiveness of randomization. Adjusted comparisons (using co-variance analysis) will be made if control for potential confounders is required. To our knowledge, there are no studies that have evaluated the impact of maternal DHA supplementation in pregnancy on infant immune function.