Sleep and Adiposity: A Prospective Twin Study

描述（由申请人提供）： 我们提出的研究的目的是阐明因果关系和机制，联系短睡眠时间（SSD）和超重或肥胖（OWO）的儿童，青少年和年轻人使用一个大的现有的前瞻性双胞胎队列。1998- 2,000年，我们在中国安庆招募了大约2,000对双胞胎，当时双胞胎的年龄在6-21岁之间。NICHD资助的一项研究（R 01 HD 049059）正在对该双胞胎队列进行跟踪（第一个F/U），以识别代谢综合征（MS）的前兆。在食物过敏基金会的支持下，第二次随访（第2 F/U）将于2007年开始（第1 F/U后约2年）。正在或将要在第一和第二F/U收集的相关数据包括流行病学和饮食问卷、人体测量（身高、体重;腰围和臀围）、坦纳分期、MS表型（总脂肪和躯干脂肪、血压、空腹血脂、空腹和OGTT后2小时胰岛素和葡萄糖）、生物标志物（IGF-1、脂联素、IL-6、TNF-α）、接合性和睡眠数据（问卷、7天日记和活动记录）。该提案寻求支持以实现以下目标：（1）在第1次和第2次随访时测量沿着将SSD与OWO联系起来的主要途径的生物标志物，包括自主神经和神经内分泌功能（心率变异性，皮质醇）;炎症（CRP）;和食欲（瘦素，生长激素释放肽）。（2）进行横断面和前瞻性双胞胎分析，以确定SSD-OWO关系;生物标志物和OWO之间的关系;并检查上述关系是否是遗传介导的，并测试年龄，性别，坦纳阶段，体力活动和营养状况的修饰作用;以及（3）检测SSD-OWO关系是否由生物标志物介导。这个中国双胞胎队列提供的独特机会是：（1）前瞻性研究设计可以评估时间关系，并为因果关系提供强有力的证据;（2）大样本量确保了我们检测因果关系的能力，不像该领域的大多数研究，这些研究的动力不足;（3）双胞胎设计，其中许多潜在的混杂因素-包括年龄，胎龄，妊娠并发症，母体营养，环境暴露和父母的社会经济地位-都是精确匹配的，（4）MZ和DZ双胞胎模型可以有效地划分环境和遗传对SSD-OWO关系的贡献;（5）数据收集的成本主要由其他资助的研究支付;和（6）研究OWO风险特别高的年龄组的能力，在这些领域中，干预对改善健康和福祉具有最大的潜力。这对双胞胎队列也是未来睡眠和OWO纵向研究的宝贵资源。

DESCRIPTION (provided by applicant): The goal of our proposed study is to elucidate cause-and-effect relationships and mechanisms that link short sleep duration (SSD) and overweight or obesity (OWO) in children, adolescents, and young adults using a large existent prospective twin cohort. We enrolled about 2,000 twin pairs in 1998-2000 in Anqing, China, when the twins were 6-21 years of age. This twin cohort is being followed (1st F/U) by a NICHD funded study (R01HD049059) to identify precursors of metabolic syndrome (MS). The second follow-up (2nd F/U) will begin in 2007 (approximately 2 years after 1st F/U) with support from the Food Allergy Foundation. Relevant data that are being or will be collected at the 1st and 2nd F/U include epidemiologic and dietary questionnaires, anthropometric measures (height, weight; waist and hip circumferences), Tanner Stages, MS phenotypes [total and truncal fat, blood pressure, fasting lipids, fasting and 2-hr post OGTT insulin and glucose), biomarkers (IGF-1, adiponectin, IL-6, TNF-a), Zygosity, and sleep data (questionnaire, 7 day diary, and actigraphy). This proposal seeks support to accomplish the following aims: (1) to measure biomarkers along the major pathways that link SSD with OWO, including Autonomic & Neuroendocrine Function (heart rate variability, cortisol); Inflammation (CRP); and Appetite (leptin, ghrelin) at the 1st and the 2nd follow-up. We will also examine other relevant biomarkers already covered by the funded studies; (2) To conduct cross-sectional and prospective co-twin analyses to determine SSD-OWO relationships; relationships between the biomarkers and OWO; and to examine if the above relationships are genetically mediated and test the modifying effects of age, gender, Tanner stage, physical activity and nutritional status; and (3) To examine whether SSD-OWO relationships are mediated by the biomarkers. The unique opportunities offered by this Chinese twin cohort are: (1) the prospective study design can assess temporal relationships and provide strong evidence for cause-and-effect; (2) the large sample size assures our ability to detect causal associations, unlike most studies in this area, which are underpowered; (3) the co-twin design, in which numerous potential confounding factors-including age, gestational age, pregnancy complications, maternal nutrition, environmental exposure, and parental socioeconomic status-are precisely matched, can minimize confounding in analysis of SSD-OWO associations; (4) the MZ and DZ co-twin models can efficiently partition environmental and genetic contributions to the SSD-OWO relationship; (5) the cost of data collection is largely covered by other funded studies; and (6) the ability to study age groups at particularly high risk for OWO, in which intervention has the greatest potential for life-long improvements in health and well-being. This twin cohort is also a precious resource for future longitudinal studies of sleep and OWO.