Rural Lifestyle Intervention Treatment Effectiveness Trial (Rural LITE)

描述（由申请人提供）： 在美国，农村地区的肥胖率、久坐不动的生活方式和冠心病的发病率高于非农村地区，然而，农村人口肥胖症的治疗却很少受到关注。在学术健康中心进行的疗效试验表明，生活方式干预可以产生足够的体重减轻，以改善健康，但很少有试验在医疗服务不足的社区环境中进行。此外，疗效研究中使用的高强度治疗是向农村环境传播的一个障碍。美国农业部合作推广服务局的现有基础设施在全国设有2900多个办事处，可以作为将生活方式干预措施带到农村地区的宝贵资源。我们的农村肥胖研究项目的初步数据显示，通过推广办公室提供的生活方式干预有希望的结果。这一系列研究的下一个合乎逻辑的步骤是确定产生有临床意义的长期减肥所需的最低治疗强度。我们建议在肥胖成人（N=542）中进行一项单盲、多中心、随机对照试验，以评估低、中、高剂量生活方式治疗与教育对照条件相比对体重两年变化的影响。低强度条件反映了社区环境中常用的分组治疗剂量，而高剂量对应于疗效试验中采用的强度水平。中等强度干预代表了我们的初步数据表明可能提供与高强度干预相当的益处的治疗剂量。我们的主要假设是，中等和高干预措施在两年内都会比低或对照条件产生更大的体重减轻。我们还将评估每种情况下达到临床显著体重减轻的参与者比例，并将检查代谢风险因素，饮食摄入量，体力活动和生活质量的变化。我们将计算干预措施的成本效益，并调查长期变化的潜在媒介。

DESCRIPTION (provided by applicant): Higher rates of obesity, sedentary lifestyle, and coronary heart disease are observed in rural than in non-rural areas of the U.S., yet the treatment of obesity in the rural population has received little attention. Efficacy trials, conducted in academic health centers, show that lifestyle interventions can produce sufficient weight reductions to improve health, but very few trials have been carried out in medically underserved community settings. Moreover, the high intensity of treatments used in efficacy studies represents a barrier to dissemination into rural settings. The existing infrastructure of the USDA Cooperative Extension Service, with over 2900 offices nationwide, may serve as a valuable resource for bringing lifestyle interventions to rural areas. Preliminary data from our rural obesity research program show promising findings for lifestyle interventions delivered through Extension offices. The next logical step in this line of research is to determine the minimum intensity of treatment required to produce clinically meaningful, long-term weight reductions. We propose to conduct a single-blind, multi-site, randomized controlled trial in obese adults (N=542) to evaluate the effects of LOW, MODERATE, and HIGH doses of lifestyle treatment on two-year changes in body weight, compared to an education CONTROL condition. The LOW intensity condition reflects the dose of group treatment commonly used in community settings, whereas the HIGH dose corresponds to the intensity level employed in efficacy trials. The MODERATE intensity intervention represents a treatment dose that our preliminary data suggest may provide benefits comparable to the HIGH intensity intervention. Our principal hypothesis is that both the MODERATE and HIGH interventions will produce greater weight reductions at two years than either the LOW or CONTROL conditions. We will also evaluate the proportion of participants in each condition, who achieve clinically significant weight losses, and we will examine changes in metabolic risk factors, dietary intake, physical activity, and quality of life. We will calculate the cost-effectiveness of the interventions, and we will investigate potential mediators of long-term change.