Costs associated with the primary prevention of type 2 diabetes mellitus in the diabetes prevention program.

OBJECTIVE To describe the costs of the Diabetes Prevention Program (DPP) interventions to prevent or delay type 2 diabetes. RESEARCH DESIGN AND METHODS We describe the direct medical costs, direct nonmedical costs, and indirect costs of the placebo, metformin, and intensive lifestyle interventions over the 3-year study period of the DPP. Resource use and cost are summarized from the perspective of a large health system and society. Research costs are excluded. RESULTS The direct medical cost of laboratory tests to identify one subject with impaired glucose tolerance (IGT) was $139. Over 3 years, the direct medical costs of the interventions were $79 per participant in the placebo group, $2,542 in the metformin group, and $2,780 in the lifestyle group. The direct medical costs of care outside the DPP were $272 less per participant in the metformin group and $432 less in the lifestyle group compared with the placebo group. Direct nonmedical costs were $9 less per participant in the metformin group and $1,445 greater in the lifestyle group compared with the placebo group. Indirect costs were $230 greater per participant in the metformin group and $174 less in the lifestyle group compared with the placebo group. From the perspective of a health system, the cost of the metformin intervention relative to the placebo intervention was $2,191 per participant and the cost of the lifestyle intervention was $2,269 per participant over 3 years. From the perspective of society, the cost of the metformin intervention relative to the placebo intervention was $2,412 per participant and the cost of the lifestyle intervention was $3,540 per participant over 3 years. CONCLUSIONS The metformin and lifestyle interventions are associated with modest incremental costs compared with the placebo intervention. The evaluation of costs relative to health benefits will determine the value of these interventions to health systems and society.