Greater Exposure to a Multilevel Multicomponent Obesity Prevention Intervention in Rural Native American Communities Is Associated With Improved Diet Quality Among Adults

Abstract Objectives Multilevel multicomponent (MLMC) intervention trials attempt to reach participants in many different settings in their lives to promote environmental and behavioral change; however, individual-level exposure to these complex interventions has rarely been evaluated. We examined the association between exposure to an MLMC intervention and changes in diet quality among Native American adults in rural communities in the Midwest and Southwest U.S. Methods The OPREVENT2 intervention was implemented over 18 months in three reservation-based communities, in the first round of the study. Nutrition and physical activity messages were delivered in local food stores, worksites, schools, and by social and community media, along with changes to food store and workplace environments to support increased physical activity and healthier food choices. A Block Food Frequency Questionnaire (FFQ) was used to calculate a Healthy Eating Index (HEI-2015) score at baseline and follow-up. At follow-up, 234 adults self-reported their exposure to intervention materials and activities via an 81-item questionnaire with illustrations. Exposure scores for each intervention component were calculated and weighted by level of interactiveness (e.g., taste tests were most interactive; posters least interactive), then summed yielding a total exposure score. Linear regression models assessed change in HEI score by participant exposure (component and total), controlling for baseline sociodemographic variables. Results The participants were majority female (73%) with a mean age of 44 (±14) years and mean total exposure score of 11.66 ± 6.71 on a scale of 0–28. Participants with higher total exposure scores had a greater increase in HEI scores compared to those who were least exposed to the intervention (b = 3.61 ± 1.90, P = 0.049). Improved diet quality was also positively associated with exposure to specific intervention components, including educational displays, posters, and radio announcements (P < 0.01). Conclusions We found a dose-response relationship between level of exposure to the intervention and diet quality among participants in the OPREVENT2 intervention. Future MLMC interventions in NA rural communities should consider using radio announcements, posters, educational displays to engage with adults and promote healthy eating. Funding Sources NHLBI.