Urban Nigeria has a significant diabetic population for which access to healthcare is often limited. A mixed-methods approach including baseline and follow-up surveys, with a focus on pre-post analysis. HbA1c levels decreased by an average of 5% (CI95: -6.2 to -3.8%) in the intervention group compared to controls. Community health workers effectively improved HbA1c control among diabetic patients in urban Nigeria, with statistically significant reductions observed. Further studies should be conducted to validate these findings and explore long-term effects. HbA1c levels, Community Health Workers, Diabetic Patients, Urban Nigeria Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.