Effect of Peer Mentors in Diabetes Self-management vs Usual Care on Outcomes in US Veterans With Type 2 Diabetes: A Randomized Clinical Trial.

Importance: Diabetes is a substantial public health issue. Peer mentoring is a low-cost intervention for improving glycemic control in patients with diabetes. However, long-term effects of peer mentoring and creation of sustainable models are not well studied. Objective: Assess the effects of a peer support intervention for improving glycemic control in patients with diabetes and evaluate a model in which former mentees serve as mentors. Design, Setting, and Participants: A randomized clinical trial was conducted from September 27, 2012, to March 21, 2018, at the Corporal Michael J. Crescenz Medical Center. US veterans with type 2 diabetes aged 30 to 75 years with hemoglobin A1C (HbA1c) greater than 8% received support over 6 months from peers with prior poor glycemic control but who had achieved HbA1c less than or equal to 7.5% (phase 1). Phase 1 mentees were then randomized to become a mentor or not to new randomly assigned participants in phase 2. Outcomes were assessed at 6 and 12 months. Data were analyzed from October 5, 2016, to September 4, 2018. Interventions: Mentors who received an initial training session and monthly reinforcement training were assigned 1 mentee and given $20 for each month they contacted their mentee at least weekly. Main Outcomes and Measures: Primary outcome was HbA1c change at 6 months. Secondary outcomes included HbA1c change at 12 months and change in low-density lipoprotein, blood pressure, diabetes quality of life, and depression symptoms at 6 and 12 months. Results: The study enrolled 365 participants into phase 1 and 122 participants into phase 2. Most participants were Black (341 [66%]) and male (454 [96%]), with a mean (SD) age of 60 (7.5) years. Mean phase 1 HbA1c change at 6 months for usual care was -0.20% (95% CI, -0.46% to 0.06%) vs -0.52% (95% CI, -0.76% to -0.29%) for mentees (P = .06). Mean phase 2 HbA1c change at 6 months for usual care was -0.46% (95% CI, -1.02% to 0.10%) vs 0.08% (95% CI, -0.42% to 0.57%) for mentees (P = .16). There were no differences in secondary outcomes or HbA1c levels at 12 months. There was no benefit to past mentees who became mentors. Conclusions and Relevance: In this randomized clinical trial, a peer mentor intervention did not improve 6-month HbA1c levels and did not have sustained benefits. Trial Registration: ClinicalTrials.gov Identifier: NCT01651117.