Role of Meal Timing in Efficacy of Bariatric Surgery in Obese Individuals

摘要 该项目的主要目标是确定日常食物摄入模式的改善是否可以 增强减肥手术的有益效果。减肥手术是目前最有效和持久的 肥胖者的减肥治疗，对心脏代谢健康有明显的长期益处。虽然 减肥手术最初的设计是为了引起机械性的热量限制，这似乎是 不是减肥的主要机制。这是因为，首先，患者失去了大量的 体重的10%不会经历过度饥饿，这通常是在热量限制之后，第二， 体重减轻量在个体之间差异很大，与术后胃袋无关 尺寸事实上，手术后体重减轻的个体间差异很大，大约25%的患者 患者可以被认为是体重减轻反应差的患者， (i.e., BMI降低< 7 kg/m2）或之后体重恢复。有趣的是，每天的食物摄入模式改变了， 例如不吃早餐和晚上吃零食，超过一半的减肥手术候选人都经历过， 这就提出了一个问题，即进餐时间的个体间差异是否会导致 减肥成功事实上，有越来越多的动物实验和人类证据表明，这种改变 日常食物摄入模式实际上会导致肥胖（详见背景技术）。却没有一 已发表的人类减肥手术研究已经测试了进餐时间和有益的饮食之间的因果关系。 减肥手术对能量平衡、血糖控制和心血管危险因素的影响。在 我们的目的是检验以下假设：1）早食者在SG后1年的BMI下降更高， 与晚食者相比; 2）与有反应的患者相比，术后体重减轻较差的患者 成功地，在一天的晚些时候有更高的饥饿相关措施; 3）实验性地限制食物摄入量 到白天在减肥手术中体重减轻不佳的患者改善了能量平衡的措施， 葡萄糖耐量和心血管功能。第一个假设将在一个观察性的 前瞻性研究（基线加1年随访后），监测非卧床膳食模式和BMI下降， 外地第二个假设将评估饥饿和食欲调节肽的24小时概况， 实验室第三个假设将在一项平行随机对照试验中进行检验， 减肥反应差的患者将接受12周的进餐时间干预或对照饮食干预， 他们的基线和干预后24小时生理结果将在实验室内测量 条件本研究将为有效性的个体间差异提供机制性的见解 并可能有助于设计以证据为基础的饮食干预措施， 来优化术后效果

Abstract The broad goal of this project is to determine whether improvements in the daily pattern of food intake can enhance the beneficial effects of bariatric surgery. Bariatric surgery is currently the most effective and durable weight loss treatment for obese individuals, with clear long-term benefit for cardiometabolic health. Though bariatric surgery was original designed to cause mechanical and consequently caloric restriction, this seems not to be the primary mechanism for weight loss. This is because, first, patients who lose a substantial amount of body weight do not experience excessive hunger which normally follows caloric restriction and, second, the amount of weight loss varies widely between individuals and is not correlated with post-surgical gastric pouch size. Indeed, the interindividual difference in post-surgical weight loss is large and approximately 25% of patients can be considered poor weight-loss responders who either do not lose a substantial amount of weight (i.e., BMI loss < 7 kg/m2) or regain the lost weight afterwards. Of interest, altered daily patterns of food intake, such as skipping breakfast and night snacking, is experienced by over half of the bariatric surgery candidates, raising the question whether interindividual differences in meal timing contribute to interindividual differences in weight loss success. Indeed, there is accumulating animal experimental and human evidence that such altered daily patterns of food intake actually contribute to obesity (detailed in the Background). However, none of the published human bariatric surgery studies have tested the causality between meal timing and the beneficial effects of bariatric surgery on measures of energy balance, glucose control, and cardiovascular risk factors. In this proposal, we aim to test the hypotheses that: 1) Early Eaters have a higher BMI loss 1 year after SG as compared to Late Eaters; 2) patients with poor post-surgical weight loss, as compared to those who respond successfully, have higher hunger-related measures late in the day; and 3) experimentally restricting food intake to the daytime in bariatric surgery patients with poor weight loss improves measures of energy balance, glucose tolerance and cardiovascular function. The first hypothesis will be tested in an observational prospective study (baseline plus after 1 year follow up), monitoring ambulatory meal patterns and BMI loss in the field. The second hypothesis will assess 24-h profiles of hunger and appetite-regulatory peptides in the laboratory. The third hypothesis will be tested in a parallel, randomized controlled trial in which patients with poor weight loss response will undergo a 12-week meal timing intervention or a control dietary intervention, and their baseline and post-intervention 24-h physiological outcomes will be measured under the in-laboratory conditions. This research will provide mechanistic insight into the interindividual differences in the effectiveness of bariatric surgery and may help in designing evidence-based dietary interventions incorporating meal timing to optimize post-surgical outcomes.