Examining sleep and social rhythms as mechanisms for weight gain after job loss

描述（由申请人提供）：超重是美国和世界范围内的一个重大公共卫生危机。虽然肥胖的根本原因是能量摄入与支出的不平衡，但导致这种不平衡的间接原因是复杂和多方面的。许多研究发现，睡眠不足会增加体重增加和不健康行为模式（热量摄入增加，体力活动减少）的风险。压力也是肥胖的一个重要间接因素，压力和睡眠不足会相互加剧。不幸的是，人们对压力和睡眠如何相互作用以及在自然环境中对个体的行为表现知之甚少。这项研究的结果将有助于科学文献基础，提供有关社会节奏，睡眠和非自愿失业后体重增加之间相互关系的数据，这是一种经常充满压力的生活事件， 扰乱了一个人的日常生活研究小组将招募250名参与者，采用前瞻性、纵向18个月设计。他们将采用社会节奏，睡眠，体重增加，饮食摄入和能量消耗的黄金标准评估，以进一步说明体重增加发生的机制。他们还将采用多变量，生长曲线建模，以获得有关社会节奏，睡眠和体重增加变化的时间优先性的有价值的信息。建议：（1）与社会节奏稳定和睡眠较好的失业者相比，社会节奏不一致和睡眠较差的失业者在18个月内的体重增加轨迹更陡峭;（2）睡眠中断介导了社会节奏中断和体重增加之间的关系;（3）再就业与上述负面轨迹的逆转有关。对这些目标的总体支持表明，睡眠和社会节奏是非自愿失业后体重增加的机制。此外，这些发现将通过测试日常行为活动，睡眠和自然环境中的压力之间的相互关系来推进肥胖研究。积极的调查结果将为针对易受伤害的个人亚群的睡眠和社会节奏的预防运动的发展提供坚实的支持。

DESCRIPTION (provided by applicant): Excess body weight is a major public health crisis in the United States and worldwide. Although the essential cause for obesity is an imbalance in energy intake v. expenditure, the indirect causes leading to this imbalance are complex and multifaceted. Numerous studies have found that insufficient sleep increases risk of weight gain and unhealthy behavioral patterns (increased caloric intake, decreased physical activity). Stress is also an important indirect factor for obesity, and stress and sleep deficiency exacerbate one another. Unfortunately, very little is known about how stress and sleep interact and manifest behaviorally for individuals in the natural environment. Findings from this study will contribute t the scientific literature base by providing data about the interrelationships between social rhythms, sleep and weight gain after involuntary job loss, a life event that is often stressful and disrupting to an individual's daily routine. The investigative team will enroll 250 participants ina prospective, longitudinal 18-month design. They will employ gold-standard assessments of social rhythms, sleep, weight gain, and dietary intake and energy expenditure in order to further specify the mechanisms by which weight gain occurs. They will also employ multivariate, growth curve modeling to elicit valuable information about the temporal precedence of changes in social rhythms, sleep, and weight gain. It is proposed that: (1) unemployed individuals with less consistent social rhythms and worse sleep will have steeper weight gain trajectories over 18 months than unemployed individuals with stable social rhythms and better sleep; (2) disrupted sleep mediates the relationship between social rhythm disruption and weight gain; and (3) reemployment is associated with a reversal in the negative trajectories outlined above. Overall support for these aims will indicate that sleep and social rhythms operate as mechanisms of weight gain in the aftermath of involuntary job loss. Moreover, these findings will advance obesity research by testing the interrelationships among daily behavioral activity, sleep, and stress in the natural environment. Positive findings will provide solid support for the development of prevention campaigns targeting sleep and social rhythms in an accessible subgroup of vulnerable individuals.