Understanding Success Factors for African Americans in Weight Loss Programs

描述（由申请人提供）：非裔美国人肥胖的高患病率和高于平均水平的严重程度是主要的公共卫生和临床问题。拟议研究的总体目标是产生急需的见解，了解如何提高非裔美国人，特别是女性的生活方式行为减肥计划的有效性，对他们来说，临床显著肥胖的水平远远超过非裔美国人男性或白色女性或男性。干预研究设计可以通过参考与暴露于各种治疗方法的非裔美国人的最佳体重结果相关的因素的经验信息来增强。该方法利用了来自三个临床试验和一个社区项目评估的数据集，这些数据集由同一个研究小组进行，并使用相同的行为咨询核心原则。拟定的分析将扩展单独研究的已发表主要结果，并特别关注研究间的汇总分析。随机临床试验有11至24个月（取决于研究和参与者入组日期）的治疗和随访。社区项目评估研究有10至20周的治疗（取决于项目交付地点和参与者的选择）。这四项研究共招募了近900名非裔美国人（约90%为女性）。合并这些研究的数据有主要优势，包括总体样本量增加;增加感兴趣亚组的样本量，例如，基于性别、教育、年龄、婚姻状况、健康状况或初始肥胖水平;提供的治疗模式以及治疗期间的脱落和出席率的变化;初始和长期随访的体重变化范围增加;以及在不同环境（研究诊所、初级保健实践和社区组织）中比较体重结果的能力。具体目标是：1）根据参与模式和水平以及初始体重变化结果的模式表征研究参与者; 2）表征能够实现并维持临床显著体重减轻的参与者; 3）表征临床或心理社会结果（如腰围，血压和QoL）改善最大的参与者;和4）比较不同治疗设置和模式下的体重变化和QoL。这些数据集中的两个或多个数据集中可用的潜在自变量反映了动机，自我效能，压力，生活事件，生活质量，来自家人和朋友的社会支持，邻里环境变量，参与模式（作为预测因素和结果）以及对行为改变建议的遵守。调查结果将产生至少四篇科学文章，描述成功因素，并解决潜在的方法，以改善参加减肥计划的非裔美国人的保留，出勤率和减肥结果。 公共卫生相关性：非裔美国人，特别是女性，患肥胖症和相关并发症的风险很高，但疗效试验的证据表明，标准的肥胖治疗方法在非裔美国人中不如白人有效。为了设计和实施更有效的计划，我们的研究小组在过去十年中对3项临床试验和一项社区计划的数据进行了拟议的二次分析，这将为与减肥计划成功相关的变量提供新的见解。

DESCRIPTION (provided by applicant): The high prevalence and above average severity of obesity in African Americans is of major public health and clinical concern. The overall objective of the proposed studies is to generate critically needed insights about ways to improve the effectiveness of lifestyle behavior weight loss programs in African Americans, particularly women, for whom levels of clinically significant obesity far exceed those in African American men or white women or men. Intervention study designs can be enhanced by reference to empirical information about factors found to be associated with the best weight outcomes in African Americans exposed to various treatment approaches. The approach takes advantage of data sets from three clinical trials and a community program evaluation, conducted by the same research group and using the same core principles of behavioral counseling. Proposed analysis will expand upon published main results of the separate studies and focus particularly on pooled analyses across studies. The randomized clinical trials had 11 to 24 months (depending on the study and on participant enrollment date) of treatment and follow up. The community program evaluation study had 10 to 20 weeks (depending on program delivery site and participant choice) of treatment. Together, the four studies enrolled nearly 900 African Americans (~90% women). There are major advantages to pooling data across these studies, including increased sample sizes overall; increased sample sizes for subgroups of interest, e.g., based on gender, education, age, marital status, health status, or initial level of obesity; variation in patterns of treatment offered and in drop out and attendance at treatment sessions; increased range of weight change for both initial and longer term follow up; and ability to compare weight outcomes in different settings (research clinic, primary care practices, and community organizations). Specific aims are to: 1) characterize study participants according to participation patterns and levels, and patterns of initial weight change outcomes; 2) characterize participants who are able to achieve and maintain clinically significant weight loss; 3) characterize participants with the largest improvements in clinical or psychosocial outcomes such as waist circumference, blood pressure and QoL; and 4) compare weight change and QoL across different treatment settings and modalities. Potential independent variables available in two or more of these data sets reflect motivation, self efficacy, stress, life events, quality of life, social support from family and friends, neighborhood context variables, participation patterns (of interest as both predictors and outcomes), and adherence to behavioral change recommendations. Findings will yield at least four scientific articles describing success factors and addressing potential ways to improve retention, attendance and weight loss outcomes in African Americans who enroll in weight loss programs. PUBLIC HEALTH RELEVANCE: African Americans, particularly women, are at high risk from obesity and related complications, but evidence from efficacy trials indicates that standard obesity treatment approaches are less effective in African Americans than in whites. To inform the design and implementation of more effective programs, the proposed secondary analysis of data from 3 clinical trials and one community-based program conducted by our research group within the last decade will provide new insights into variables related to success in weight loss programs.