Priority Medicines for Europe and the World 2013 Update. Background Paper 6 - Priority Diseases and Reasons for Inclusion. BP 6.18 - Obesity
(2013; 38 pages)


Obesity is a chronic and multi-factorial disease and one of the most important causes of morbidity and premature mortality worldwide.

Currently, over a billion people are overweight and half a billion are obese. In more than half of the EU countries one in two individuals are overweight or obese. The epidemic is still increasing in many European countries, whereas in some it seems to have slowed down. In the United States, obesity has been declared the number one health threat.

Non-surgical and non-pharmacotherapeutical treatment options include diet, exercise, behaviour modification and psychological support. The effect size has been reported with a single digit weight loss in kilograms which can be maintained. In contrast to experimental settings, implementing life-style interventions in routine primary care that reduce morbidity at population level have proven to be difficult.

There are only very limited pharmacotherapeutic treatment options. Overall, pharmacotherapy has played a minor role in the treatment of obesity. Only one medicine is currently available in most European countries (orlistat). No current pharmacotherapy possesses the efficacy needed to produce clinically significant weight loss (at least 5 to 10% weight loss) in a large proportion of morbidly obese patients in the long-term. More research is needed on whom to treat, adherence factors and the regain of body weight after discontinuation of pharmacotherapy to more adequately evaluate the cost-effectiveness of pharmaceutical therapy. It has been challenging to develop pharmacotherapy that has gained acceptance by medicines regulatory authorities or remained available for a long time due to their adverse benefit/risk profiles that have emerged with use.

Bariatric surgery is currently the only intervention providing significant and long-term weight loss for the morbidly obese (approximately 20% weight loss after ten years) which improves diabetes, hypertension and quality-of-life. However, it is associated with surgical risks (mortality less than 1%), long-term digestive problems and nutritional deficiencies. Savings might be achieved six years after the surgery for the health care systems but whether there are savings after ten years is unclear.

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