Energy Expenditure and Gastric-Bypass Surgery

描述(申请人提供)：肥胖是一种流行病，对健康和社会具有广泛的影响。减肥手术是一种成功的治疗方法，可以实现并保持体重减轻，改善肥胖的并存状态。这项研究将探索接受胃旁路减肥手术的受试者的体重减轻的能量机制，这一点到目前为止还没有明确的定义。在能源储备发生实质性变化的任何情况下，都有必要研究食物摄入量和能量支出变化的作用。减肥手术后，能量摄入量明显下降。然而，关于能量消耗的组成部分，特别是活动生热作用如何变化的信息很少。这不是一个微不足道的问题。事实上，体力活动和活动产热的变化对于理解为什么一些人比其他人通过减肥手术减掉的体重更多是至关重要的。能量平衡包括能量摄入和能量消耗。能量消耗包括基础代谢率、食物的热效应和活动生热作用。活动生热又可分为运动活动生热和非运动活动生热(NEAT)。后者甚至比前者更难衡量。大多数美国人，以及世界卫生组织III级肥胖者中的绝大多数人，从事的有目的的运动相对较少，因此在体育活动中消耗的大部分能量都是通过整洁。这项研究的目的是评估接受减肥手术的患者术后活动产热是否比手术前增加。我们将使用有效的体力活动监测系统和双标签水，在手术前立即以及术后6个月和18个月再次评估非运动活动产热。PAMS已经在苗条和肥胖的人身上得到了验证。这是为了评估能量消耗，活动生热和在减肥最好的阶段和一旦减肥达到平台期的整洁。这将使我们能够解决我们的主要假设，即与手术前相比，接受减肥手术的患者术后6个月和12个月的活动生热作为每日总能量消耗的一部分增加。总体而言，肥胖是个人健康和医疗保健的主要负担。减肥手术已被证明是有益的，但对其机制尚不清楚。科学需要存在，而且有技术可用来揭示活动、产热和能量消耗在减肥手术后减肥中的作用。这可能会对减肥手术和总体上的肥胖管理产生重大影响。

DESCRIPTION (provided by applicant): Obesity is an epidemic with widereaching implications for health and society. Bariatric surgery is a successful therapy for achieving and maintaining weight loss and improving obesity comorbidiities. This study will explore the energetic mechanisms of weight loss in subjects undergoing gastric bypass bariatric surgery, which until now has not been clearly defined. In any scenario where there are substantial changes in energy stores, it is necessary to examine the role of changes in food intake and energy expenditure. After bariatric surgery, it is evident that energy intake declines. However, there is very little information as to how the components of energy expenditure, and in particular activity thermogenesis, change. This is not a trivial issue. In fact, changes in physical activity and activity thermogenesis could be crucial for understanding why some people lose more weight than others with bariatric surgery. Energy balance comprises energy intake and energy expenditure. Energy expenditure includes basal metabolic rate, thermic effect of food, and activity thermogenesis. Activity thermogenesis can be further divided into exercise activity thermogenesis and non-exercise activity thermogenesis (NEAT). The latter is even more difficult to measure than the former. Most Americans, and the vast majority of those with World Health Organization Class III obesity engage in relatively little purposeful exercise, and hence the majority of energy expended in physical activity is through NEAT. The aim of this study is to assess whether activity thermogenesis increases in patients undergoing bariatric surgery post-operatively compared to pre-operatively. We will assess non-exercise activity thermogenesis using a validated Physical Activity Monitoring System and doubly labeled water, immediately pre-operatively and again at 6 and 18 months post-operatively. PAMS has been validated in lean and obese individuals. This is to assess energy expenditure, activity thermogenesis and NEAT during the phase of greatest weight loss and once weight loss has plateaued. This will permit us to address our primary hypothesis that activity thermogenesis as a fraction of total daily energy expenditure increases in patients undergoing bariatric surgery 6 and 12 months post-operatively, compared to pre-operatively. Overall, obesity is a major personal health and health care burden. Bariatric surgery has been shown to be beneficial without a clear understanding of the mechanism. The scientific need exists and the technology is available to uncover the role of activity thermogenesis and energy expenditure in weight loss after bariatric surgery. This may have dramatic implications for bariatric surgery and obesity management in general.