Behavioral and Biological Rhythms in Children's Obesity-Related Health Disparities

项目摘要/摘要 儿童肥胖症被认为是一种流行病，不同的社会经济地位(SES)存在显著差异。的确有 因此，迫切需要确定预防和治疗肥胖的新的、可改变的危险因素 儿童，特别是那些风险较大的儿童。令人信服的证据，植根于昼夜生物学和 我们对昼夜节律的理解，并得到了对啮齿动物和成年动物的新研究的支持，表明 除了关注我们在饮食、活动和睡眠行为中的投入程度外，它可能还 了解我们从事这些行为的时机和一致性(即，行为 节律)，以降低肥胖风险。越来越多的证据表明，一致的行为节律 有潜在的昼夜节律，比如在生物夜晚睡觉，在生物夜晚进食 一天与改善新陈代谢过程和体重调节有关。虽然鲜为人知 关于行为节律如何优化儿童的体重调节，来自相关系列的发现 儿科研究支持那些有啮齿动物和成年动物的人，并强调了行为的潜在重要性 防止体重超标的节律。理解行为节律在体重调节中的作用 对于来自较低SES背景的儿童可能特别重要，因为他们可能面临更大的风险 对于由于经济不景气和邻里不利而扰乱行为节奏的人，将他们 增加了超重的风险。此外，了解SES、行为 学龄儿童的节律和体重调节集中在一段时间段，当许多 贯穿青春期的健康行为是形成的，因此可能代表着 优化体重调节。因此，本研究建议将176名5-8岁的儿童从 将不同的SES背景纳入为期16个月的观察性研究。孩子们将完成五个为期10天的课程 在整个研究期间(基线、4个月、8个月、12个月和16个月)进行评估，在此期间将衡量以下各项： 睡眠的时间和一致性(通过活动记录仪)，进食的时间和分布(通过24小时饮食回忆)， 体力活动和久坐活动的时间和一致性(通过加速测量和自我报告)， 生物钟(暗光褪黑素开始；DLMO)，家庭和邻里环境的测量，以及 人体测量学(身高、体重、肥胖)。这项拟议工作的主要目的是评估：a)如何 行为节律影响儿童的身体质量指数(BMI)轨迹，以及b)SES如何影响行为 节奏，因此体重指数轨迹。二级目标将评估昼夜节律因素(即昼夜节律阶段和 昼夜相位角)和家庭和邻里环境影响行为节律。 探索性目标还将评估行为、昼夜节律和环境因素对 儿童BMI轨迹，包括行为节律和BMI之间关联的潜在缓和 通过昼夜节律相位和相角确定的轨迹。

PROJECT SUMMARY/ABSTRACT Pediatric obesity is considered an epidemic with striking disparities by socioeconomic status (SES). There is therefore a pressing need to identify novel, modifiable risk factors for obesity prevention and treatment in children, particularly those who are at greater risk. Compelling evidence that is rooted in circadian biology and our understanding of circadian rhythms, and is supported by emerging work with rodents and adults suggests that in addition to focusing on how much we engage in eating, activity and sleep behaviors, it may also be important to understand the timing and consistency with which we engage in these behaviors (i.e., behavioral rhythms) for obesity risk reduction. Mounting evidence demonstrates that behavioral rhythms that are aligned with underlying circadian rhythms, such as sleeping during the biological night and eating during the biological day are associated with improved metabolic processes and weight regulation. Although less is known regarding how behavioral rhythms may optimize weight regulation in children, findings from related lines of pediatric research support those with rodents and adults and highlight the potential importance of behavioral rhythms for excess weight gain prevention. Understanding the role of behavioral rhythms in weight regulation for children from lower SES backgrounds may be particularly important given that they may be at greater risk for disruptions to behavioral rhythms due to economic adversity and neighborhood disadvantage, placing them at increased risk for excess weight gain. Further, understanding associations between SES, behavioral rhythms and weight regulation in young school-aged children focuses on a time period when a number of health behaviors that carry through adolescence are shaped and thus may represent an opportune time for optimizing weight regulation. The present study therefore proposes to enroll 176 children 5-8 years old from diverse SES backgrounds into a 16-month observational study. Children will complete five 10-day assessments across the study (baseline, 4, 8, 12, and 16 months) during which the following will be measured: timing and consistency of sleep (via actigraphy), timing and distribution of eating (via 24-hour dietary recalls), timing and consistency of physical and sedentary activities (via accelerometry and self-report), timing of the circadian clock (dim light melatonin onset; DLMO), measures of the home and neighborhood environment, and anthropometrics (height, weight, adiposity). The primary aims of this proposed work are to assess: a) how behavioral rhythms affect body mass index (BMI) trajectories in children, and b) how SES affects behavioral rhythms and thus BMI trajectories. Secondary aims will assess how circadian factors (i.e., circadian phase and circadian phase angle) and the household and neighborhood environments affect behavioral rhythms. Exploratory aims will also assess the relative influence of behavioral, circadian and environmental factors on children's BMI trajectories, including potential moderation of associations between behavioral rhythms and BMI trajectories by circadian phase and phase angle.