The Diabetes Prevention Program (DPP) enrolled 3,234 participants with impaired glucose tolerance (IGT) and fasting hyperglycemia, aiming to assess the effectiveness and cost-effectiveness of lifestyle and metformin interventions in preventing diabetes. Participants were randomized to receive either a lifestyle intervention, metformin, or placebo. The lifestyle intervention focused on achieving at least a 7% weight reduction through diet and physical activity, while metformin was administered at a dose of 850 mg twice daily after an initial month at 850 mg once daily.
Key Findings:
- Diabetes Incidence: At 10 years, the cumulative incidence of diabetes was significantly lower among lifestyle (26.5%) and metformin (41.5%) participants compared to placebo (52.4%).
- Quality of Life: Adherent lifestyle and metformin participants accrued more QALYs (6.80 and 6.74, respectively) than placebo participants (6.67).
- Cost-Effectiveness: From a health system perspective, lifestyle and metformin interventions were cost-saving relative to placebo. The cumulative undiscounted per participant cost of the lifestyle intervention was $4,810, compared to $2,934 for metformin and $768 for placebo.
Intervention Details:
- Lifestyle Intervention: Included a 16-session core curriculum, monthly follow-up visits, and group sessions aimed at reinforcing behavioral changes for weight loss and physical activity.
- Metformin Intervention: Participants were encouraged to continue metformin and participate in a group lifestyle intervention during the DPPOS maintenance phase.
Cost Analysis:
- The study calculated direct medical costs associated with the interventions and non-intervention-related medical care, finding that the costs of lifestyle and metformin were offset by the savings from reduced diabetes incidence and associated complications.
- The analysis also considered direct non-medical costs, including food, exercise, and transportation, from a societal perspective.
Conclusion:
The findings underscore the effectiveness of lifestyle and metformin interventions in preventing diabetes among high-risk individuals. These interventions not only reduce the risk of diabetes but also improve quality of life and are cost-effective from a health system perspective. The study advocates for the adoption of these preventive measures in real-world clinical practice to mitigate the growing burden of diabetes.
