Testing a very low-carbohydrate diet version of the Diabetes Prevention Program to reduce risk factors for type 2 diabetes

摘要 三分之一的美国成年人患有前驱糖尿病，并处于患2型糖尿病及其破坏性疾病的高危状态 对健康的影响。具有里程碑意义的糖尿病预防计划(DPP)试验表明，一种资源-- 将饮食和体力活动改变相结合的强化一对一计划可以降低3年内患心脏病的风险 与常规护理相比，2型糖尿病患者减少了58%。因此，民进党被认为是最好的 营养计划如何预防疾病的例子，以及疾病控制和 预防(CDC)和其他机构建议将DPP作为成人糖尿病前期患者的一线治疗方案。这个 CDC的国家糖尿病预防计划(NDPP)是DPP试验课程的改编，使用 以小组为基础的交付。它教导参与者遵循低脂肪、限制卡路里的饮食，因为这是 30多年前，当民进党试验设计时，流行的饮食建议。NDPP现已在以下位置提供 遍布全美的1500个地点，由联邦医疗保险和其他付款人报销。然而，尽管 广泛使用，只有36%的参与者实现了≥减重5%的计划目标，并且当 经测量，HbA1c平均下降不到0.1%。我们假设，调整NDPP以教授 不同的饮食策略--极低碳水化合物饮食(VLCD)--将提高NDPP的有效性 作为降低2型糖尿病风险的工具。碳水化合物摄入量是影响餐后摄入量的最大因素 血糖和VLCD-由于其降低血糖、体重和抗高血糖需求的能力 药物-现在是美国糖尿病协会推荐用于治疗2型糖尿病的药物。至 迄今为止，还没有高质量的随机对照试验来测试VLCD在降低 患有糖尿病前期的成人中患2型糖尿病的风险，也没有任何DPP的VLCD版本的随机试验。至 为了填补这一关键空白，我们的团队开发并试运行了NDPP的VLCD版本(VLC- NDPP)，由我们的疾控中心认可的社区合作伙伴密歇根国家肾脏基金会提供。 我们的研究结果表明，VLC-NDPP是可行和可接受的。我们现建议进行一项12- 月，1：1，随机试验，将300名超重或肥胖的糖尿病前期成年人分配到 标准NDPP或VLC-NDPP。主要结果是血糖控制(通过HbA1c测量)， 次要结果包括体重、体脂百分比、血糖变异性和炎症。我们 还将使用混合方法探索血糖控制和饮食坚持的障碍和促进者。 随着2型糖尿病的流行和对个性化干预的了解不断增加， 迫切需要为人群水平的2型糖尿病预防提供更多有效的选择 战略。如果VLC-DPP显示出希望，这项试验将是一项多站点试验的先兆，其发病率为 以2型糖尿病为主要结局。

ABSTRACT One-third of U.S. adults have prediabetes and are at high risk of developing type 2 diabetes and its devastating health consequences. The landmark Diabetes Prevention Program (DPP) trial demonstrated that a resource- intensive, one-on-one program combining diet and physical activity changes, could reduce the 3-year risk of type 2 diabetes by 58% compared with usual care. Consequently, the DPP is considered one of the best examples of how a nutritional program can prevent disease, and the Centers for Disease Control and Prevention (CDC) and others recommend the DPP as a first-line treatment for adults with prediabetes. The CDC’s National Diabetes Prevention Program (NDPP) is an adaptation of the DPP trial curriculum, using group-based delivery. It teaches participants to follow a low-fat, calorie-restricted diet, as this was the prevailing dietary advice when the DPP trial was designed over 30 years ago. The NDPP is now available at >1,500 sites throughout the United States and reimbursed by Medicare and other payors. Yet, despite widespread availability, only 36% of participants achieve the program goal of ≥5% body weight loss and, when measured, HbA1c reduces on average less than 0.1%. We hypothesize that adapting the NDPP to teach a different dietary strategy—a very-low-carbohydrate diet (VLCD)—will increase the effectiveness of the NDPP as a tool for type 2 diabetes risk reduction. Carbohydrate intake is the strongest factor impacting post-prandial glycemia, and a VLCD—due to its ability to reduce glycemia, weight, and the need for anti-hyperglycemic medications—is now recommended by the American Diabetes Association for treatment of type 2 diabetes. To date, there are neither high-quality, randomized controlled trials testing how effective a VLCD is at reducing the risk of type 2 diabetes among adults with prediabetes, nor randomized trials of VLCD versions of any DPP. To begin to fill this critical gap, our team has developed and pilot tested a VLCD version of the NDPP (VLC- NDPP), delivered by our CDC-recognized community partner, the National Kidney Foundation of Michigan. Our findings demonstrate that a VLC-NDPP is feasible and acceptable. We now propose to conduct a 12- month, 1:1, randomized trial that will assign 300 overweight or obese adults with prediabetes to either the standard NDPP or the VLC-NDPP. The primary outcome is glycemic control (measured by HbA1c), with secondary outcomes including body weight, body fat percentage, glycemic variability, and inflammation. We will also explore the barriers to and facilitators of glycemic control and dietary adherence using mixed methods. As the prevalence of type 2 diabetes and the understanding of personalized interventions continue to increase, there is a critical need to provide additional effective options for population-level type 2 diabetes prevention strategies. If the VLC-DPP shows promise, this trial would be a precursor to a multi-site trial with incidence of type 2 diabetes as the primary outcome.