Long-Term Mobile-Based Glycemic Intervention for Secondary Prevention in Patients With Diabetes Undergoing Surgical Revascularization: Multicenter Randomized Controlled Trial

Background: Despite the growing amount of patients who underwent coronary artery bypass grafting (CABG) in low- and middle-income countries like China, their glucose control was suboptimal, likely due to poor adherence to healthy lifestyles and preventive medications. Mobile health tools facilitating secondary prevention seem promising, but evidence focusing on this high-risk population is scarce. Objective: This study aimed to evaluate the significance of mobile health tools in long-term glycemic management for post-CABG patients with comorbid diabetes mellitus. Methods: GUIDEME (glycemic control using mini program-based intervention in patients with diabetes undergoing coronary artery bypass to promote self-management) is a multicenter, open-label, closed-user group, randomized controlled trial, in which 1066 patients with diabetes who had recently undergone CABG were enrolled and allocated into 2 groups. Patients in the control group received conventional health education before discharge, whereas those in the intervention group additionally received automatic delivery of bite-sized health education and medication reminders through a smartphone app during the 6 months after discharge. The primary end point was a change in glycosylated hemoglobin (HbA1c) from baseline to 6 months. Results: Among the 1066 eligible participants enrolled, a total of 1038 (97.4%) had completed the follow-up, while 1000 (93.8%) had 6-month HbA1c results available. Although only 79 (14.9%) patients in the intervention group were defined as active users, a greater reduction of HbA1c in the intervention group was observed (adjusted between-group mean difference -0.13, 95% CI -0.25 to -0.01; P=.04). The intervention group also had a high proportion of good medication adherence (96.1% vs 93.2%, P=.04). There was no difference between the 2 groups regarding the secondary end points. Conclusions: Health education and medication reminders based on smartphone app achieved a statistically significant but modest between-group difference in HbA1c, the clinical relevance of which remains uncertain.