Effect of a peer support intervention on glycemic control and its implementation cost among patients with diabetes on follow up at a tertiary hospital: a randomized controlled trial

Diabetes imposes a growing global burden due to rising healthcare costs and reduced quality of life resulting from its complications. There is increasing interest in the role that peers may play in supporting positive health behaviors among individuals with diabetes. However, studies evaluating both the clinical effectiveness and economic feasibility of peer support interventions remain limited. Therefore, this study aimed to evaluate the effect of a group-based peer support intervention on glycemic control and implementation cost among patients with diabetes. A randomized controlled trial with a 1:1 allocation ratio was conducted at Ayder Comprehensive Specialized Hospital (ACSH). A total of 100 patients with diabetes were randomly assigned to the intervention ( n = 50) and control ( n = 50) groups. The intervention arm received structured peer support sessions delivered in three sequential rounds in addition to usual care, whereas the control arm received usual care alone. Glycemic outcomes were assessed using glycated hemoglobin (HbA1c) measured at baseline and at the 6-month follow-up. The economic evaluation included only direct implementation costs associated with the peer support intervention program. Ninety-seven participants completed the trial (intervention n = 48; control n = 49), with comparable baseline glycemic and biochemical characteristics. After six months, the intervention group showed significantly greater improvements in HbA1c (DiD: −0.4%, p = 0.02) and fasting blood glucose (DiD: −4.4 mg/dL, p = 0.03) compared with the control group. However, changes in body mass index and lipid profile parameters were modest and did not differ significantly between groups in the difference-in-differences analysis. The total implementation cost of the peer support program was US$690 for three rounds, equivalent to US$14.38 per participant. Linking program costs to glycemic outcomes yielded an estimated US$36 per 1% reduction in HbA1c, indicating a favorable cost profile relative to the glycemic improvement achieved. Peer support improved glycemic control with a relatively low implementation cost, supporting its potential as a practical and scalable strategy for diabetes management in resource-constrained settings. Integrating such programs into routine diabetes care may strengthen affordable and sustainable diabetes management approaches. Future studies with longer follow-up periods are needed to evaluate the sustainability of clinical benefits and the long-term economic impact of these interventions. ClinicalTrials.gov identifier: NCT07499375; date of registration: January 1, 2025.