Franz Marion J, Boucher Jackie L, Rutten-Ramos Stephanie, VanWormer Jeffrey J
J Acad Nutr Diet. 2015 Sep;115(9):1447-63. doi: 10.1016/j.jand.2015.02.031. Epub 2015 Apr 29.
The majority of people with type 2 diabetes are overweight or obese, and weight loss is a recommended treatment strategy. A systematic review and meta-analysis was undertaken to answer the following primary question: In overweight or obese adults with type 2 diabetes, what are the outcomes on hemoglobin A1c (HbA1c) from lifestyle weight-loss interventions resulting in weight losses greater than or less than 5% at 12 months? Secondary questions are: What are the lipid (total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides) and blood pressure (systolic and diastolic) outcomes from lifestyle weight-loss interventions resulting in weight losses greater than or less than 5% at 12 months? And, what are the weight and metabolic outcomes from differing amounts of macronutrients in weight-loss interventions? Inclusion criteria included randomized clinical trial implementing weight-loss interventions in overweight or obese adults with type 2 diabetes, minimum 12-month study duration, a 70% completion rate, and an HbA1c value reported at 12 months. Eleven trials (eight compared two weight-loss interventions and three compared a weight-loss intervention group with a usual care/control group) with 6,754 participants met study criteria. At 12 months, 17 study groups (8 categories of weight-loss intervention) reported weight loss <5% of initial weight (-3.2 kg [95% CI: -5.9, -0.6]). A meta-analysis of the weight-loss interventions reported nonsignificant beneficial effects on HbA1c, lipids, or blood pressure. Two study groups reported a weight loss of ≥5%: a Mediterranean-style diet implemented in newly diagnosed adults with type 2 diabetes and an intensive lifestyle intervention implemented in the Look AHEAD (Action for Health in Diabetes) trial. Both included regular physical activity and frequent contact with health professionals and reported significant beneficial effects on HbA1c, lipids, and blood pressure. Five trials (10 study groups) compared weight-loss interventions of differing amounts of macronutrients and reported nonsignificant differences in weight loss, HbA1c, lipids, and blood pressure. The majority of lifestyle weight-loss interventions in overweight or obese adults with type 2 diabetes resulted in weight loss <5% and did not result in beneficial metabolic outcomes. A weight loss of >5% appears necessary for beneficial effects on HbA1c, lipids, and blood pressure. Achieving this level of weight loss requires intense interventions, including energy restriction, regular physical activity, and frequent contact with health professionals. Weight loss for many overweight or obese individuals with type 2 diabetes might not be a realistic primary treatment strategy for improved glycemic control. Nutrition therapy for individuals with type 2 diabetes should encourage a healthful eating pattern, a reduced energy intake, regular physical activity, education, and support as primary treatment strategies.
大多数2型糖尿病患者超重或肥胖，减肥是推荐的治疗策略。开展了一项系统评价和荟萃分析，以回答以下主要问题：在超重或肥胖的2型糖尿病成年人中，12个月时体重减轻大于或小于5%的生活方式减肥干预对糖化血红蛋白（HbA1c）有何影响？次要问题包括：12个月时体重减轻大于或小于5%的生活方式减肥干预对血脂（总胆固醇、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇和甘油三酯）和血压（收缩压和舒张压）有何影响？此外，减肥干预中不同宏量营养素含量对体重和代谢有何影响？纳入标准包括在超重或肥胖的2型糖尿病成年人中实施减肥干预的随机临床试验、至少12个月的研究持续时间、70%的完成率以及12个月时报告的HbA1c值。11项试验（8项比较了两种减肥干预措施，3项将减肥干预组与常规护理/对照组进行了比较），共6754名参与者符合研究标准。在12个月时，17个研究组（8类减肥干预措施）报告体重减轻小于初始体重的5%（-3.2千克[95%CI：-5.9，-0.6]）。对减肥干预措施的荟萃分析报告称，对HbA1c、血脂或血压无显著有益影响。两个研究组报告体重减轻≥5%：一项针对新诊断的2型糖尿病成年人实施的地中海式饮食，以及在“糖尿病健康行动”（Look AHEAD）试验中实施的强化生活方式干预。两者都包括规律的体育活动以及与健康专业人员的频繁接触，并报告了对HbA1c、血脂和血压有显著有益影响。5项试验（10个研究组）比较了不同宏量营养素含量的减肥干预措施，报告在体重减轻、HbA1c、血脂和血压方面无显著差异。大多数针对超重或肥胖的2型糖尿病成年人的生活方式减肥干预导致体重减轻小于5%，并未带来有益的代谢结果。体重减轻>5%似乎对HbA1c、血脂和血压产生有益影响是必要的。要达到这种体重减轻水平需要强化干预，包括能量限制、规律的体育活动以及与健康专业人员的频繁接触。对于许多超重或肥胖的2型糖尿病患者来说，减肥可能不是改善血糖控制的现实主要治疗策略。2型糖尿病患者的营养治疗应鼓励健康的饮食模式、减少能量摄入、规律的体育活动、教育和支持作为主要治疗策略。
