Objective: The results of the metformin substudy of the United Kingdom Prospective Diabetes Study (UKPDS) were applied through modelling techniques to the Swiss setting, allowing a cost-effectiveness analysis of the management of overweight type-2 diabetes patients with either conventional glycaemic control or intensive control with metformin from the Swiss third-party payer perspective.
Methods: Occurrence of diabetes-related complications was simulated using a Markov model. Probabilities for complications were taken from the UKPDS, and costs were retrieved from published sources. Total direct costs (costs of diabetes therapy plus costs of treating complications) and survival over an 11-year period were determined for cohorts randomised to either conventional glycaemic control or intensive control with metformin. Changes in life expectancy were calculated for conventional versus intensive control with metformin. Extensive sensitivity analysis was performed.
Results: Mean costs per patient over the 11-year follow-up period (discounted at 5% per annum) were CHF 10,877 and CHF 9950 for patients randomised to either conventional control or intensive control with metformin respectively. Intensive control with metformin led to improved survival (0.43 life-years gained per patient) over the 11-year-period. Outcomes were most sensitive to variations in the acquisition costs of metformin. Changes in the event rates and costs related to myocardial infarction, renal failure, and stroke also had important impacts.
Conclusions: Within the limitations of the modelling study, intensive glycaemic control with metformin was cost- and life-saving in overweight type-2 diabetes patients in the Swiss setting.