OBJECTIVES: Prediabetes, a state of impaired glucose regulation that precedes diabetes, affects nearly 110 million Chinese adults. Lifestyle interventions alone or a combined approach with metformin proved to be effective to prevent or delay the onset of diabetes, reduce the incidence of complications, and ultimately lead to significant healthcare savings. However, the cost-effectiveness of such interventions remains unknown, which is essential for policy making and resource allocation. Our study aims to estimate the lifetime cost-effectiveness of metformin combined with lifestyle interventions versus lifestyle interventions alone among pre-diabetic subjects.

METHODS: A Markov model was developed to conduct a cost-utility analysis (CUA) among adults with impaired glucose regulation. The model incorporated data from the China Diabetes Prevention Program（CDPP) and real-world evidence, to simulate the long-term health and economic outcomes of two intervention strategies. The analysis was conducted from the healthcare system perspective, with costs and quality-adjusted life years (QALYs) as the primary outcomes. Model time horizon was lifetime with a one-year cycle time. A 5% discounts rate was used for both costs and QALYs.

RESULTS: The study revealed that the group receiving both metformin and lifestyle interventions experienced a higher total QALY gain of 10.33 compared to 10.23 in the lifestyle-only group. The total cost for the combination therapy was CNY 59,095.24, while it was CNY 54,267.18 for the lifestyle-only intervention. The incremental cost-effectiveness ratio (ICER) for the combination therapy was CNY 45,052.80 per QALY, equaling to 0.5 times per capita GDP of China in 2023, suggesting that the intervention is cost-effective.

CONCLUSIONS: In adults with impaired glucose regulation, the combination of metformin and lifestyle interventions is projected to be cost-effective. This study supports the integration of metformin therapy into prediabetes management protocols, emphasizing the economic viability and clinical benefits of early intervention with antidiabetic drugs.