Efficacy of surgery in the management of obesity-related type 2 diabetes mellitus

Background: It is estimated that up to 80% of persons with diabetes mellitus type 2 are overweight and in these patients it is recognized that effective weight control can lead to improvement or even resolution of their diabetes (Colagiuri et al.). All currently carried out operations for morbid obesity have been shown to improve diabetes, but there appears to be a variable response to surgery depending on several surgical and patient factors. Methods: In this prospective review, we analysed the change in the diabetic status in 72 patients undergoing three different bariatric procedures in a single institution over 30 months. A review of the published work comparing the efficacy of the various procedures in achieving improvement or resolution of diabetes was also carried out and correlated to our findings. Results: At an average follow up of 13 months, 50% of patients who had placement of laparoscopic adjustable gastric band had an improvement or resolution of their diabetes, compared with 95% of patients who had had laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass. Two of 12 (17%) laparoscopic adjustable gastric band patients had normal blood glucose levels off all diabetic medications compared with 7 of 21 (33%) laparoscopic sleeve gastrectomy and 27 of 39 (69%) Roux-en-Y gastric bypass patients. There was no significant association between the amount of weight lost and the return to euglycaemia. Conclusion: Direct comparison has shown a significant difference in the effects of different forms of bariatric surgery on type 2 diabetes, this is in keeping with evidence that surgery can lead to improvement in diabetes additional to that obtained by weight loss alone.