Treatment of the metabolic syndrome by bariatric surgery

Abstract

Bariatric surgery is regarded as metabolic surgery due to its effects on the metabolic syndrome and type 2 diabetes. At present an estimated 350,000 bariatric operations are performed worldwide per year. Laparoscopic adjustable gastric banding (LAGB) and laparoscopic Roux-en-Y gastric bypass (RYGB) are the two more commonly performed procedures. Obesity responds well to bariatric with major long-lasting weight loss, most pronounced after RYGB, where the mean weight loss is about 40 kg or 15 BMI units. Some of the benefits after RYGB are independent of weight loss, and the remission of type 2 diabetes is observed a few days after the operation and depends on changes in gut hormones responses, especially a tenfold increase in GLP-1, which improves insulin secretion. After gastric banding the remission of diabetes depends more on weight loss. Bariatric surgery reduces cardiovascular risk factors including hypertension, lipid disturbances and non-alcoholic fat liver and reduces mortality of diabetes, cardiovascular diseases and cancers. Bariatric surgery also improves quality of life. The acute complications to surgery are infection, bleeding and anastomotic leak. Long-term complications are nutritional deficiencies including vitamins and minerals and anaemia. Some patients have dumping after meals. Few patients developed postprandial hypoglycaemia after RYGB. About 25 % of the patients needed plastic surgery to provide relief from excessive skin tissue. Gastric bypass surgery has improved our understanding of the regulation of body weight and pathophysiology of type 2 diabetes, which may facilitate the development of novel therapies for obesity and diabetes.