A simple dietary message to improve dietary quality for metabolic syndrome

描述（由申请人提供）：总体目标是比较两种干预方法对代谢综合征患者饮食改变的疗效。代谢综合征影响了近27%的美国成年人，根据国家胆固醇教育计划成人治疗小组III的描述，代谢综合征是预防冠心病的国家优先事项。在代谢综合征的建议中，减肥是最重要的。最近三篇综述文章的结果一致认为，添加膳食纤维有助于减肥和维持减肥效果；膳食纤维对代谢综合征的几个组成部分也有临床益处，包括腰围、葡萄糖和脂质稳态以及胰岛素控制。尽管如此，美国成年人的平均纤维摄入量还不到推荐水平的一半。此外，以饮食改变为目标的干预措施通常不能在短期内坚持所有建议，并在长期内保持饮食变化。饮食依从性差的一个因素可能是饮食指南的复杂性。我们提出一种简化的饮食干预策略，侧重于饮食质量的一个关键方面，纤维摄入，将克服与饮食干预通常相关的不良依从性，提高整体饮食质量。我们将从初级保健机构招募240名超重和肥胖的成年人，他们符合代谢综合征的诊断标准。两种饮食改变干预的效果将在一项随机对照试验中进行比较，每组120例患者。这两种方法是：1)美国心脏协会（AHA）膳食指南；2)一个简单的饮食改变条件，重点是增加纤维。两种情况下的患者都将接受为期3个月的强化饮食指导，随后是9个月的维持期。这两种情况都将接受由注册营养师领导的个人和小组会议的饮食指导。评估，包括饮食、人体测量、血压、空腹血糖、糖化血红蛋白（HbA1c）、血脂、胰岛素、炎症标志物、药物使用、抑郁、生活质量和身体活动将在基线和随机化后6- 12个月进行。强化干预后3个月的评估将测量体重、饮食和代谢综合征指标的短期变化。我们假设，与随机分配到AHA饮食组的参与者相比，随机分配到高纤维饮食组的参与者在随访中体重减轻、代谢健康改善和饮食质量显著提高。这样一个简单的信息，如果在临床环境中被发现对减肥、代谢健康、饮食质量和依从性有效，那么可能是作为公共卫生信息进行测试的理想选择。公共卫生相关性：确定减肥和代谢健康的简单饮食建议可能会证明一个简单的公共卫生信息对冠心病预防和代谢综合征的影响。在一项随机临床试验中，我们建议比较两种干预方法对代谢综合征患者饮食改变预防冠心病的疗效。这两种方法是：1)美国心脏协会膳食指南；2)一个简单的饮食改变条件，重点是增加纤维。我们假设，促进高纤维摄入的信息可能是有可能产生广泛影响的简单信息。

DESCRIPTION (provided by applicant): The overall goal is to compare the efficacy of two intervention approaches to dietary change among patients with the metabolic syndrome. Metabolic syndrome, which affects nearly 27% of US adults, is a national priority for prevention of CHD as described by the National Cholesterol Education Program's Adult Treatment Panel III. Weight loss is paramount in recommendations for metabolic syndrome. Results from three recent review articles agreed that adding dietary fiber can aid weight loss and weight loss maintenance; dietary fiber also exerts clinical benefits on several components of the metabolic syndrome, including waist circumference, glucose and lipid homeostasis, and insulin control. Despite this, the average fiber intake of adults in the United States is less than half recommended levels. In addition, interventions that target dietary change have typically not been successful with adherence to all recommendations in the short term, and with maintaining changes in diet over the longer term. A contributing factor to poor dietary adherence is likely of the complexity of dietary guidelines. We propose that a simplified dietary intervention strategy that focuses on a key aspect of dietary quality, fiber intake, will overcome the poor adherence typically associated with dietary interventions and improve overall diet quality. We will recruit 240 overweight and obese adults from a primary care setting who meet diagnostic criteria for metabolic syndrome. The efficacy of the two dietary change interventions will be compared in a randomized controlled trial, with 120 patients per group. The two approaches are 1) the American Heart Association (AHA) Dietary Guidelines; and 2) a simple dietary change condition that focuses on increasing fiber. Patients in both conditions will receive intensive dietary instruction for 3 months, followed by a 9 month maintenance phase. Both conditions will receive dietary instructions via individual and group sessions led by registered dietitians. Assessments, including diet, anthropometrics, blood pressure, fasting blood glucose, glycosylated hemoglobin (HbA1c), blood lipids, insulin, inflammatory markers, medication use, depression, quality of life, and physical activity will be conducted at baseline and at 6-, and 12-months after randomization. A 3-month post-intensive intervention assessment will measure short-term changes in body weight, diet, and metabolic syndrome indicators. We hypothesize that participants randomized to the higher fiber condition will have significantly greater weight loss, improvements in metabolic health, and dietary quality at follow-up, compared to those randomized to the AHA diet condition. Such a simple message, if found efficacious for weight loss, metabolic health, dietary quality and adherence in a clinical setting might then be ideal for testing as a public health message. PUBLIC HEALTH RELEVANCE: Identifying a simple dietary recommendation for weight loss and metabolic health may demonstrate potential for a simple public health message to impact CHD prevention and metabolic syndrome. In a randomized clinical trial, we propose to compare the efficacy of two intervention approaches to dietary change for CHD prevention among persons with metabolic syndrome. The two approaches are 1) the AHA Dietary Guidelines; and 2) a simple dietary change condition that focuses on increasing fiber. We hypothesize that a message promoting high fiber intake may be the simple message that has potential to produce broad impact.