[Obesity - principles of surgical therapy].

The prevalence of obesity and the number of surgeries for morbid obesity are increasing worldwide. Conservative therapy is largely ineffective in producing maintenance of weight loss in morbidly obese patients, and surgery is therefore increasingly considered as the only available option for these patients. Until approximately 15 years ago, many patients and physicians regarded bariatric surgery as dangerous because it required a large laparotomy and was associated with a relatively high risk of complications. Since laparoscopic techniques have become available, however, the number of patients referred for surgery has been increasing steadily. The principles of standard procedures are independent of access, whether open or laparoscopic. The pathophysiologic mechanisms are restriction, malabsorption, or a combination of both. New findings in the field of endocrine and humoral regulations have shown that surgical procedures can induce complex changes in the regulation of enterohormones. These mechanisms are the basis for metabolic effects, especially in cases of diabetes mellitus type 2. Obesity surgery is known to be the most effective and longest-lasting treatment for morbid obesity and many related conditions, but mounting evidence now suggests that it may also be among the most effective treatments for metabolic diseases and conditions such as type 2 diabetes, hypertension, high cholesterol, nonalcoholic fatty liver disease, and obstructive sleep apnea. Surgery for severe obesity goes far beyond weight loss; benefits include improved quality of life and extended life expectancy.