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

描述（由申请人提供）：黑人婴儿在美国面临最高的早产率（18%），有很高的早产相关喘息疾病的发生率，并且往往维生素D水平较低。这项[比较有效性]研究的目标是确定一个vit。D补充策略，最大限度地减少婴儿反复喘息。长期以来人们一直认为维生素对骨骼健康很重要，越来越多的证据表明维生素对骨骼健康很重要。D可能在许多器官系统的调节和发育中发挥作用。D通路调节肺部炎症，影响支气管平滑肌的形态发生、结构和细胞生长和存活。维特。D暴露有可能使细胞因子表达从Th1（较少过敏）表型扭曲为Th2（更过敏）表型。由于发育不成熟，早产儿可能特别容易受到维生素d的任何积极或消极影响。补充维生素D对肺、气道和免疫系统的影响。我们的初步数据得到了文献的支持，表明过度的攻击性。补充维生素D可能会无意中增加黑人早产儿的喘息，而不是白人早产儿；然而,维特。从理论上讲，缺乏维生素D也可能会因为呼吸道病原体的易感性而增加喘息。该研究是一项随机临床试验，比较两种不同的肠内维生素D补充策略对300名出生在300/7-366/7周胎龄的黑人早产儿复发性喘息的影响。维生素D需求不是最佳维生素。血清D水平已经确定。我们将测试两种策略：(1)持续补充至6岁，并对早产进行调整；(2)当最低膳食摄入量达到200 IU/天时停止补充。具体目的是描述每种策略对（目标1）复发性喘息和（目标2）[过敏致敏]和特应性的影响。我们将（目标3）探讨vit和vit之间的关系。血清D水平与复发性喘息。我们假设策略II将更有效地通过减少复发性喘息，[过敏致敏]和整体医疗保健利用来促进肺部健康，并将足以预防临床vv。D缺乏。我们也假设最优的vit。血清D水平将低于其他人群的标准。理论关联：Vit。D状态和健康状态。

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.