Effect of Birth Order and Genetics on Infant Parenting and Obesity Risk

描述（由申请人提供）：干预护士启动婴儿健康成长（INSIGHT）研究是一项正在进行的前瞻性、随机、对照试验，评估响应性父母干预的有效性，旨在预防276名新生儿体重快速增加和儿童肥胖。利用INSIGHT的基础设施和广泛的数据收集，拟议的研究增加了两个主要部分，即招募第二胎的兄弟姐妹，并收集兄弟姐妹及其父母的基因样本。具体来说，这项转化研究将a)前瞻性地评估与肥胖相关的养育方式的异同以及第一胎和第二胎兄弟姐妹之间的体重相关结果；b)探索与食欲、气质和肥胖易感性相关的兄弟姐妹之间的遗传差异如何影响亲子互动、反应性养育程度和体重状况。c)确定INSIGHT研究干预是否在参与仅观察二胎评估的家庭中发生结转效应。国家健康和营养检查调查数据表明，需要进行早期干预以预防肥胖：26.7%的2-5岁儿童已经超重或肥胖。这些发现令人担忧，因为超重的婴幼儿在以后的生活中患肥胖症及其合并症的风险会增加。婴儿期是开始预防肥胖的好时机，因为它是快速生长和发育可塑性的关键时期，具有长期的代谢和行为后果。INSIGHT的初步研究结果表明，肥胖预防计划的重点是反应性喂养、喂养责任分工和健康的饮食选择，可以改善首胎婴儿的体重相关结果。有趣的是，来自不同文化的数据表明，尽管与怀孕有关的儿童肥胖风险因素（孕前体重指数高、妊娠期体重增加高、妊娠期糖尿病的发生、出生体重高）在二胎妊娠期间更为常见，但头胎儿童肥胖的风险更高。这表明，与父母教养有关的产后因素是导致第一胎和第二胎儿童肥胖风险差异的原因。利用响应式养育的概念框架，可以假设母亲由于从第一个孩子身上获得的经验而提高了响应性和更适当的照顾行为。这一假设将通过比较在提议的资助期间可能出生的bb100名第二胎兄弟姐妹与他们的哥哥姐姐来验证，另外的目标是探索肥胖遗传易感性的差异和观察到的食欲和气质的差异如何调节反应性养育与一岁时体重状况之间的关联。

DESCRIPTION (provided by applicant): The Intervention Nurses Start Infants Growing on Healthy Trajectories (INSIGHT) study is an ongoing prospective, randomized, controlled trial evaluating the efficacy of a responsive parenting intervention designed to prevent rapid infant weight gain and childhood obesity among 276 first-born infants. Capitalizing on the infrastructure and extensive data collection occurring as part of INSIGHT, the proposed research adds two major pieces by enrolling second born siblings and collecting genetic specimens from both siblings and their parents. Specifically, this translational research will a) prospectively evaluate obesity-related parenting similarities and differences as well as weight-related outcomes between first and second-born siblings, b) explore how genetic differences among siblings that are associated with appetite, temperament, and obesity susceptibility affect parent-child interactions, degree of responsive parenting, and weight status, and c) determine whether INSIGHT study intervention carryover effects occur among families participating in the observation-only second-born child evaluation. National Health and Nutrition Examination Survey data demonstrate the need for early intervention to prevent obesity: 26.7% of children aged 2-5 years are already overweight or obese. These findings are concerning as overweight infants and toddlers are at increased risk of obesity and its co-morbidities later in life. Infancyis an opportune time to begin obesity prevention because it is a critical period of rapid growth and developmental plasticity with long-lasting metabolic and behavioral consequences. The promising pilot study results that informed INSIGHT demonstrated that an obesity prevention program focused on messages of responsive feeding, division of feeding responsibility, and healthy dietary choices can improve weight-related outcomes for first-born infants. Interestingly, data from diverse cultures have shown that first-born children have a higher risk for obesity despite the fact that pregnancy related risk factors for childhood obesity (high pre-pregnancy body mass index, high gestational weight gain, occurrence of gestational diabetes, high birth weight) are more common during pregnancies with second-born children. This suggests that postnatal factors related to parenting are the cause for the disparity between first and second born children's obesity risk. Using the conceptual framework of responsive parenting, it can be hypothesized that mothers have improved responsiveness and more appropriate caretaking behaviors due to the experience gained with their first child. This hypothesis will be tested by comparing the >100 second-born siblings that can be expected to be born during the proposed funding period with their older siblings with the additional goal to explore how differences in genetic susceptibility to obesity and observed differences in appetite and temperament moderate associations between responsive parenting and weight status at age one year.