Summary
20 million people in the US have Type 2 Diabetes. The disease is a leading cause of blindness, renal failure and amputations and patients have a demonstrably shortened life span. It is a chronic condition that medical treatment has thus far only been able to control, not cure. Morbid obesity is a cause of Type 2 diabetes. Bariatric surgery for morbid obesity has resulted in cures for Type 2 Diabetes. Interestingly, the success of gastric bypass in curing Type 2 Diabetes is due more to postoperative metabolic changes than simple weight loss, and this suggests that bariatric surgery may become an even more common operation in the near future.
Analysis
Surgery has become the most effective therapy for morbid obesity. Surgical results are superior to those achieved by conservative treatment both in terms of weight loss and durability. As a result, the number of bariatric surgeries performed in the US has risen 9-fold from 1998 to 2004 (13,000 to 121,000) with a concomitant drop in operative morbidity. The increase in surgeries has contributed to our understanding of the mechanism underlying Type 2 Diabetes.
It was initially thought that resolution of Type 2 Diabetes following bariatric surgery was due to weight loss. While this may play a role, as evidenced by the improvement in diabetes in some patients who lose weight following gastric banding or without surgery, numerous studies have demonstrated the remarkable findings of improved insulin sensitivity and return to normal blood glucose levels within days of gastric bypass surgery, long before weight loss occurs.
Gastric bypass involves exclusion of the duodenum and portion of the foregut; this seems critical to the metabolic changes seen in animal models and post operative patients. Evidence of this is seen when evaluating gastric bypass to laparoscopic gastric banding. A meta review of 136 studies comparing gastric bypass to lap band demonstrated that, while both procedures resulted in durable weight loss, gastric bypass resulted in complete resolution of diabetes in 83% of patients compared to 48% of lap band patients. Gastric bypass is a superior treatment for Type 2 Diabetes.
Taken as a whole, not only is surgery an effective treatment for morbid obesity, but it also is an effective cure for Type 2 Diabetes. Surgery is obviously not to be undertaken lightly, yet medical treatment of diabetes can only hope to manage diabetes and its serious comorbidities. Surgery offers the only cure for what has heretofore been a chronic disease. As surgery becomes safer and we gather longer term patient data, the surgical treatment of this endocrine disease is likely to become even more widely accepted. I would expect the number of gastric bypass procedures to increase as non-morbidly obese people with Type 2 Diabetes pursue surgery as a treatment option.
