Cost-effectiveness analysis of acarbose in the treatment of patients with impaired glucose tolerance

OBJECTIVE: To perform a cost-effectiveness analysis of treatment with acarbose in patients with impaired glucose tolerance (IGT) in comparison with conventional treatment (based on medical counseling on diet and health and without drug treatment) from the perspective of the public payer. MATERIAL AND METHOD: A cost-effectiveness analysis was performed using data on efficacy, the incidence of diabetes mellitus type 2 (DM2) and cardiovascular events from the STOP-NIDDM clinical trial of acarbose treatment vs. placebo. The study used a decision tree analysis to estimate the health and economic impact of the two alternative treatments in a population of 1,000 patients over a period of 40 months. Resource use and cost data refer to the Spanish health care system. RESULTS: In the base case, acarbose treatment was slightly dominant over conventional treatment since it achieved improved outcomes at an even lower cost. Sensitivity analysis revealed that acarbose treatment lost dominance due to a moderately positive cost-effectiveness ratio for avoided progression to DM2 in some scenarios. The cost-effectiveness ratio was particularly sensitive to the cost of cardiovascular treatments, the risk of progression to DM2, the daily doses of acarbose, and the publicly funded share of the cost of this drug. CONCLUSIONS: Acarbose treatment in patients diagnosed with IGT appeared to be the dominant alternative compared with conventional treatment. The cost per avoided progression to DM2 and per additional individual free of a cardiovascular event was moderately low in some of the scenarios included in the sensitivity analysis. For a more comprehensive evaluation of the possible treatment of patients with IGT, the alternatives under comparison and the time horizon of the study would need to be increased and more refined health outcome measures, comprising all the treatment's health effects, would need to be introduced.