Metabolic surgery, weight regain and diabetes re-emergence.

INTRODUCTION: The poor success of clinical treatment of Type 2 Diabetes Mellitus (T2DM2) increased interest in metabolic surgery, which has been considered a promising alternative for the control of obese or non-obese diabetics. However, there is still no long-term follow-up to evaluate the duration of diabetes remission, and if weight regain would be associated to recurrence. AIM: 1) To describe the results of diabetic patients with a BMI < 30 and < 35 kg/m² submitted to the following types of metabolic surgery: ileal interposition and sleeve gastrectomy, Roux-en-Y gastric bypass (RYGB), adjustable gastric banding, duodeno-jejunal exclusion and duodeno-jejunal bypass; 2) to evaluate the possible relapse of diabetes after occurrence of weight regain on long-term after bariatric surgery. METHOD: An expositive and historical literature review about metabolic surgery in diabetic patients with BMI < 30 and < 35 kg/m² was conducted, and systematic review of the association between disease relapse and weight regain after bariatric surgery. RESULTS: After analysis of 188 published papers on Medline until 2010, three papers were selected, which included 269 patients who underwent RYGB. Pre-operatory BMI was between 37 and 60 kg/m² and follow-up of three to 16 years. CONCLUSIONS: 1) Two studies showed association between weight regain and recurrence of type 2 diabetes, while the third did not show this association when comparing groups with and without weight regain; 2) metabolic surgery has shown adequate control of T2DM2 in class I obese subjects; however, the non-obese group still need a long-term evaluation, considering the risk of diabetes recurrence when after weight regain.