Cost-effectiveness of sibutramine in the treatment of obesity

Background. This study reports incremental cost-utility of sibutramine compared to diet and lifestyle advice for the treatment of obesity. Method. The model estimates the costs and quality of life benefits associated with weight loss itself and the reduced incidence of coronary heart disease (CHD) and diabetes in the "healthy obese." The key source of effectiveness data is 2 randomized controlled trials over 12 months. Utility gain per kilogram lost is analyzed using Short Form-36 data from sibutramine trials. The impact on CHD is estimated using the Framingham risk equation, which relates age/sex/body mass index to risk of heart disease. The reduced incidence of diabetes due to weight loss is estimated from published literature. A life tables approach was used to calculate the cost per quality-adjusted life year (QALY) of 1 year's treatment with sibutramine compared to diet and lifestyle advice. Results. The incremental cost per QALY of sibutramine is pound4780. Sensitivity analyses show that this result is sensitive to utility associated with weight loss and the frequency of monitoring. Conclusions. Sibutramine is a cost-effective treatment for obesity when combined with diet and lifestyle advice.