ABSTRACT: The burden of chronic diseases like diabetes and obesity is rapidly increasing in low and lower-middle income countries. This work assesses the long-term efficacy of a social-network based community health program for the management and prevention of type 2 diabetes. Methods:The 4-month Microclinic Social Network Behavioral Health Program in Jordan (J-MCP) was an intervention for obesity and diabetes prevention and management conducted in the Kingdom of Jordan. Weight and HbA1c were collected at baseline, end of the 4-month program, and then 12 and 24?months after baseline. Multi-level longitudinal repeated measures analysis estimated the long-term change in metabolic outcomes, and estimated the intra-class correlations (ICCs) for assessing the degree of clustering that different social network levels, of microclinic group vs. classroom group vs. clinic geographic location vs. cohort temporal wave, contributed to body weight and glycemic changes. Results:Of 315 participants, 83.2% completed the J-MCP program, with 90% followup at 12-months, and 70% at 24-months. At the end of the 4-month program, participants experienced a -2.8?kg (95% CI: -3.6 to -2.1) mean body weight decrease, a corresponding -1.1?kg/m2 (-1.3 to -0.8) BMI decrease, and a -0.5% reduction in HbA1c (-0.6 to -0.3). At year 1, we observed significant mean weight reduction of -1.8?kg (-2.7 to -0.9), a corresponding -0.7?kg/m2 (-1.0 to -0.4) reduction in BMI, as well as a -0.4% (-0.6 to -0.3) sustained reduction in HbA1c. At 2?years, participants sustained mean weight loss of -1.6?kg (-2.6 to -0.5), a -0.42?kg/m2 (-0.8 to -0.04) reduction in BMI, and an absolute -1.0% (-1.1 to -0.8) sustained reduction in HbA1c. Analyzing different social network levels, classroom group explained ~50% of total clustering of total weight loss and 22% of HbA1c trajectories during the short 4?month intervention. However, during 12 and 24?month followup, microclinic social group clustering explained ~75% to 92% of long-term weight loss trajectories, and 55% of long-term HbA1c trajectories. The pattern of 1-2?year sustainability of the weight and HbA1c decreases was largely attributed to the microclinic social network clusters. Conclusion:Results demonstrate that the 4-month J-MCP behavioral intervention yielded important 2-year sustained weight and HbA1c reductions, which were mostly attributed to microclinic social groups.
