Cost-effectiveness of the interventions in the primary prevention of diabetes among Asian Indians: within-trial results of the Indian Diabetes Prevention Programme (IDPP).

OBJECTIVE In the Indian Diabetes Prevention Programme (IDPP), a 3-year randomized, controlled trial, lifestyle modification (LSM) and metformin helped to prevent type 2 diabetes in subjects with impaired glucose tolerance (IGT). The direct medical costs and cost-effectiveness of the interventions relative to the control group are reported here. RESEARCH DESIGN AND METHODS Relative effectiveness and costs of interventions (LSM, metformin, and LSM and metformin) in the IDPP were estimated from the health care system perspective. Costs of intervention considered were only the direct medical costs. Direct nonmedical, indirect, and research costs were excluded. The cost-effectiveness of interventions was measured as the amount spent to prevent one case of diabetes within the 3-year trial period. RESULTS The direct medical cost to identify one subject with IGT was Indian rupees (INR) 5,278 ($117). Direct medical costs of interventions over the 3-year trial period were INR 2,739 ($61) per subject in the control group, INR 10,136 ($225) with LSM, INR 9,881 ($220) with metformin, and INR 12,144 ($270) with LSM and metformin. The number of individuals needed to treat to prevent a case of diabetes was 6.4 with LSM, 6.9 with metformin, and 6.5 with LSM and metformin. Cost-effectiveness to prevent one case of diabetes with LSM was INR 47,341 ($1,052), with metformin INR 49,280 ($1,095), and with LSM and metformin INR 61,133 ($1,359). CONCLUSIONS Both LSM and metformin were cost-effective interventions for preventing diabetes among high risk-individuals in India and perhaps may be useful in other developing countries as well. The long-term cost-effectiveness of the interventions needs to be assessed.