Change in physical activity levels and predictors of success in DPP-based community lifestyle intervention efforts

INTRODUCTION: Efficacy trials, including the U.S. Diabetes Prevention Program (DPP), demonstrated that lifestyle interventions focusing on increased physical activity (PA) and modest weight loss (WL) can prevent or delay the onset of type 2 diabetes and reduce cardiovascular disease risk. Based upon knowledge gained from these trials, the DPP lifestyle intervention has been modified for delivery in community settings using the DPP goals of 150 minutes moderate PA per week and 7% WL. Intervention impact on weight change has been frequently described, but reporting of program success related to PA is limited, creating gaps in knowledge regarding the effectiveness of intervention for increasing PA level and on the participant socio-demographic characteristics or external factors, such as season, associated with PA levels. METHODS: The first investigation identifies DPP-translation studies using PubMed and Ovid databases and determines the extent to which studies report PA assessment and outcomes. The second and third investigations report PA results from an NIH-funded study designed to test the feasibility and effectiveness of a DPP-based translation, Group Lifestyle Balance™, delivered in diverse community settings. The investigations utilize PA data collected via the Modifiable Activity Questionnaire and a brief lifestyle questionnaire from 223 participants enrolled in the study. These investigations examine how intervention and season independently impact PA level and the participant baseline characteristics and program adherence markers that predict success in meeting PA and WL goals. RESULTS: A review of the published DPP translation literature identified issues of inconsistent assessment and incomplete reporting of PA results. Examination of PA information from the lifestyle intervention translation study showed the significant independent effects of lifestyle intervention and season on increasing leisure PA and revealed baseline BMI, pre-diabetes status, session attendance, and self-monitoring of PA and diet as predictors of achieving both PA and WL success. PUBLIC HEALTH SIGNIFICANCE: The literature review exposed the need for standardized PA assessment and results reporting in translation research. The original investigations reported in this dissertation advance the understanding of lifestyle intervention effectiveness for increasing PA levels independent of season and provide insight as to the participant characteristics and adherence behaviors that enhance individual success