Wheezing in Black Preterm Infants: Impact of Vitamin D Supplementation Strategy

描述(由申请者提供)：黑人婴儿面临着美国最高的早产率(18%)，早产儿相关喘息疾病的比率很高，而且维生素D水平往往较低。这项[比较有效性]研究的目标是确定VIT。D补充策略，最大限度地减少婴儿期反复喘息。长期以来，人们一直认为维生素T对骨骼健康很重要，越来越多的证据表明，维生素T。D可能在许多器官系统的调节和发育中发挥作用。D途径调节肺部炎症，影响支气管平滑肌的形态发生、结构、细胞生长和存活。维特。D暴露有可能使细胞因子的表达从Th1(过敏程度较低)向Th2(过敏程度更高)转变。由于发育不成熟，早产儿可能特别容易受到维生素T的任何积极或消极影响。对肺部、呼吸道和免疫系统的补充。我们的初步数据，得到了文献的支持，表明过于咄咄逼人的VIT。补充维生素D可能会无意中增加黑人早产儿婴儿的喘息，但不会增加白人早产儿的喘息；然而，维生素T。理论上，缺乏D还可能通过易受呼吸道病原体的影响而增加喘息。这项拟议的研究是一项随机临床试验，比较了两种不同的维生素D肠内补充策略对300名胎龄为300/7-366/7周的早产儿婴儿期反复喘息的影响，对这一人群来说，两者都不是维生素D。D要求也不是最优的VIT。已经建立了D血清水平。我们将测试两种策略：(I)持续补充到6个月。经早产调整的年龄，以及(Ii)当达到每日最低饮食摄入量200IU时停止补充剂。具体目的是描述每种策略对(目标1)反复喘息和(目标2)[过敏性致敏]和特应性的影响。我们将(目标3)探索VIT与VIT之间的关系。D血清水平和反复喘息。我们假设，通过最小化反复喘息、[过敏性致敏]和整体医疗保健利用率，策略II将在促进肺健康方面更有效，并且将足以预防临床VIT。D缺乏。我们还假设了最优VIT。D血清水平将低于其他人群的正常水平。理论协会：VIT。D状态和健康状况。

DESCRIPTION (provided by applicant): Black infants face the highest rates of prematurity in the U.S. (18%), have high rates of prematurity-associated wheezing illnesses, and tend to have lower vitamin D levels. The goal of this [comparative effectiveness] study is to identify a vit. D supplementation strategy that minimizes recurrent wheezing in infancy. Long recognized as important for bone health, a growing body of evidence suggests that vit. D may play a role in the regulation and development of many organ systems. The D pathway regulates lung inflammation and impacts morphogenesis, structure, and cell growth and survival in bronchial smooth muscle. Vit. D exposure has the potential to skew cytokine expression from a Th1 (less allergic) to a Th2 (more allergic) phenotype. Due to their developmental immaturity, preterm infants may be particularly vulnerable to any positive or negative effects of vit. D supplementation on the lung, airway, and immune system. Our preliminary data, supported by the literature, suggests that overly aggressive vit. D supplementation may inadvertently increase wheezing in infancy in black, but not white, preterm infants; however, vit. D deficiency could theoretically also increase wheezing via vulnerability to respiratory pathogens. The proposed study is a randomized clinical trial comparing the effect of two different enteral vitamin D supplementation strategies on recurrent wheezing in infancy in 300 black infants born preterm at 300/7-366/7 wks gestational age, a population for whom neither vit. D requirements nor optimal vit. D serum levels have been established. We will test two strategies: (I) sustained supplementation until 6 mo. of age adjusted for prematurity, and (II) cessation of supplementation when a minimum dietary intake of 200 IU/day is reached. The specific aims are to characterize the effect of each strategy on (aim 1) recurrent wheezing and (aim 2) [allergic sensitization] and atopy. We will (aim 3) explore the relationship between vit. D serum levels and recurrent wheezing. We hypothesize that strategy II will be more effective in promoting pulmonary health by minimizing recurrent wheezing, [allergic sensitization], and overall healthcare utilization, and will be sufficient to prevent clinical vit. D deficiency. We also hypothesize that optimal vit. D serum levels will be lower than the norms for other populations. Theoretical Association: Vit. D Status and Health.