A health economic model to assess the long-term effects and cost-effectiveness of orlistat in obese type 2 diabetic patients

OBJECTIVES - Obesity is a common condition in type 2 diabetic patients. Treating obesity may enhance hypoglycemic treatment and contribute to the reduction of long-term microvascular and macrovascular complications. Orlistat reduces cardiovascular risk factors in obese type 2 diabetic patients. The objectives of this study were to estimate the long-term clinical consequences of this weight loss and the resulting cost-effectiveness of treating obese type 2 diabetic patients with orlistat. RESEARCH DESIGN AND METHODS - A Markov model was developed to predict, over a 10-year period, the complication rates and mortality with and without a 2-year orlistat treatment, assuming a 5-year catch-up period after treatment. A stepwise approach was used to obtain the clinical data. First, the impact of weight loss with orlistat on HbA(1c) blood pressure, and cholesterol was assessed; then, the impact on mortality and micro- and macrovascular complications of decreasing these risk factors was applied. Four subgroups were studied based on the presence of risk factors. RESULTS - Cost-effectiveness varies between 3,462 Euro/life-year gained (LYG) for obese diabetic patients with hypertension and hypercholesterolemia and 19,986 Euro/LYG for obese diabetic patients without other risk factors. The latter result is not robust according to sensitivity analyses. CONCLUSIONS - Our results suggest that orlistat is cost-effective in the management of obese type 2 diabetic patients, especially in those with the presence of hypercholesterolemia and/or hypertension. Evidence on longer-term benefits of orlistat (>2 years) will be of importance for future decision-making.