Randomized Trial of Social Network Lifestyle Intervention for Obesity: MICROCLINIC Intervention Results and 16-Month Follow-up
Authors: Eric L Ding1, Kathleen T Watson2, Nancy Bui2, Leila Makarechi2, Leslie Lang2, Marta R Prescott2,
Sha’Tia N Safford3, Dipti Banerjee3, Harold W Campbell4, Josh A Rushakoff4, Daniel E Zoughbie3; 1Dept of Nutrition, Harvard Sch of Public Health, Boston, MA, 2MCI Rsch Div, Microclinic International, San Francisco, CA, 3Executive office, Microclinic International, San Francisco, CA, 4Executive Office, Microclinic International, San Francisco, CA
BACKGROUND: Obesity has been suggested to propagate within social networks. A social network program was engineered to contagiously propagate healthy lifestyles and leverage pre-existing social networks to decrease obesity. We expand upon a 9- to 10-month intervention program with 16-month follow-up to investigate the power of social networks in the first ever long-term randomized trial.
METHODS: Based in rural Appalachian region of Kentucky, we investigate the Microclinic Social Network Behavioral Health Intervention (MSN) lifestyle intervention in a resource-limited but socially cohesive area with high obesity prevalence. Social clusters of 2-8 individuals who participated together in a program with weekly physical activity, nutrition, health education and social activity sessions led by health-educators; controls had access to standard care from local county health department. Bodyweight and waist circumference were collected in follow-up waves during intervention, plus at 16 months after baseline in a 52% sample subcohort. Longitudinal analyses utilized multilevel repeated- measures mixed models, with multilevels of neighborhood center, classroom, and social cluster (i.e. microclinic) to examine the change in health outcomes in program participants vs. controls.
RESULTS: Study enrolled 552 participants, comprised of 242 social clusters, among 27 classroom clusters, and from 5 neighborhood cohorts. Participants were 85.8% women, mean age 50.9 years (13.8), mean BMI 36.2 (7.6). From baseline to end of intervention period, MSN intervention group showed decreased body weight of -6.52 lbs (95% CI: -8.57 to -4.47; P<0.001), and improved central adiposity with decreased waist circumference of -1.24 inches (-1.85 to -0.63; P<0.001), relative to controls. In subcohort at 16 months, decreases in weight (-4.70 lbs, -7.56 to -1.84) and waist circumference (-0.99 inches, -1.81 to -0.17) were maintained. CONCLUSIONS: Expanded and long-term findings demonstrate the effectiveness of Microclinic Social Network Behavioral Health Intervention for obesity control in resource limited settings. Results hold promise for socially engineering and leveraging the power of social networks interventions to propagate healthy lifestyle behaviors.