Bariatric treatments for adult obesity - Institute of Health Economics

concluded that adding orlistat to LM was associated with best value-for-money in the sub-group ofobese patients with IGT.Roux et al. 21 compared the cost-effectiveness of usual care with four weight loss strategies—dietonly, diet and orlistat; diet and exercise; and a combination of diet, exercise, and behaviourmodification—for women aged ≥ 35 years with a BMI ≥ 25 kg/m 2 . A first-order Monte Carlomodel was applied to simulate the natural history of obesity over a lifetime horizon. The study wasconducted from a societal perspective in the US, with clinical evidence mainly derived from RCTs.The medical costs considered in the analysis were the costs of medication, physician services,laboratory and diagnostic tests, and the costs of obesity-related morbidity and mortality. Nonmedicalcosts such as fitness and travel costs as well as the costs of patients’ time were also included.Results indicated the treatment option with the lowest cost per life year (LY) saved or per QALYgained was the combination of diet, exercise, and behaviour modification; as compared to usual care,the cost of the combined treatment was $63,153 per LY saved and $13,174 per QALY gained. Thestudy concluded that the weight loss program combining diet, exercise, and behaviour modificationwas the most cost-effective for overweight and obese women.Hampp et al. 17 constructed a decision analytic model to assess the clinical and economic impact ofrimonabant in combination with LM (LCD and exercise) for adult patients with a BMI ≥ 30 kg/m 2or a BMI ≥ 27 kg/m 2 with treated or untreated dyslipidaemia or hypertension. Five treatmentalternatives were:rimonabant at a daily dose of 20mg plus LM for 1 year;rimonabant plus LM for one year followed by placebo plus LM for 1 year;rimonabant plus LM for 2 years;placebo plus LM for 2 years; no intervention,The time horizon of the analysis was 5 years. The study applied clinical evidence demonstrated in alarge RCT and healthcare costs from a US payer’s perspective. The cost categories included the costsof medications, dietician and physician visits, and treatment for myocardial infarction and diabetes.Results indicated that rimonabant plus LM for one year and of rimonabant plus LM for 1 yearfollowed by placebo plus LM for 1 year were dominant options in that they were more costly andless effective, as compared to the other alternatives. The cost of for rimonabant treatment for 2years was $75,255 per QALY gained as compared to LM, and $55,349 per QALY gained ascompared to no intervention. The study concluded that adding rimonabant to LM reduced theincidence of obesity-related morbidity and improved health-related quality of life, but at aconsiderable cost.Brennan et al., 18 Warren et al., 19 and Ara et al. 20 constructed decision-tree models to evaluate theclinical impact and cost-effectiveness of sibutramine in combination with lifestyle counselling forpatients with a BMI ≥ 30 kg/m 2 , as compared to lifestyle counselling alone. These studies adopted apayers’ perspective and had a 5-year horizon (1 year sibutramine treatment plus 4 years follow-up).The Brennan study was performed in Germany, the Warren study in the UK and the US, and theAra study in four European countries (Finland, Germany, Switzerland, and the UK). Clinicalevidence applied in these studies was based on an RCT. The costs considered in these studies wereof sibutramine treatment, fatal and nonfatal coronary heart disease (CHD), and diabetes. Comparedwith lifestyle counselling alone, the cost of sibutramine per QALY gained was $18,484 in Germany(as showed in the Brennan study); $9723 in the US and $7841in the UK (as showed in the WarrenBariatric treatments for adult obesity 166