Effectiveness and cost-effectiveness of an app and rewards-based intervention in type 2 diabetes: A randomised controlled trial

Aim: Digital health interventions and economic incentives have shown promise in facilitating diabetes self-management, though evidence is limited. Therefore, this study aimed to evaluate the effectiveness and cost-effectiveness of a comprehensive app-based diabetes self-management programme with rewards for healthy behaviours and health outcomes.

Materials and methods: The TRIal to slow the Progression Of Diabetes (TRIPOD) study was an open-label, parallel-group, randomised controlled trial conducted at Duke-NUS Medical School, Singapore. Adults with Type 2 Diabetes (diabetes), HbA_1c of 7.5%-11.0% (inclusive) and taking at least one oral diabetes medication were eligible. In total, 269 participants were randomised across three arms [Usual care (UC): 117, diabetes management programme (DMP) (intervention without rewards): 36, DMP+ (intervention with rewards): 116]. Data were analysed using intention-to-treat analysis with change in HbA_1c at month 12 between DMP+ and UC as the primary outcome. Cost-effectiveness of DMP+ relative to UC was also calculated.

Results: Mean HbA_1c improved by 0.1% in UC and by 0.5% in DMP+ at 12 months, revealing a mean difference of 0.4% (95% confidence interval (CI): -0.70, -0.08, p = 0.015). The odds ratio of HbA_1c improvements of >0.5% was 2.12 (95% CI: 1.17, 3.85, p = 0.013) for DMP+ relative to UC. The incremental cost-effectiveness ratio of DMP+ relative to UC was SGD8,516 (USD6,531) per quality-adjusted life year gained if effectiveness could be maintained with a single year of intervention.

Conclusions: A comprehensive app-based diabetes self-management programme with rewards for healthy behaviours and health outcomes (DMP+) cost-effectively improved glycaemic control in Type 2 diabetes patients. Organizations focusing on value-based healthcare should consider subsidising similar interventions.