Bariatric surgery and diabetes remission: Who would have thought it?

Type 2 diabetes mellitus (T2DM) and obesity are increasingly common and major global health problems. The Edmonton obesity staging system clearly pointed towards increased mortality proportionate to the severity of obesity. Obesity itself triggers insulin resistance and thereby poses the risk of T2DM. Both obesity and T2DM have been associated with higher morbidity and mortality and this calls for institution of effective therapies to deal with the rising trend of complications arising out of this dual menace. Although lifestyle changes form the cornerstone of therapy for both the ailments, sustained results from this modalities is far from satisfactory. While Look AHEAD (action for HEAalth in diabetes) study showed significant weight loss, reduction in glycated hemoglobin and higher remission rate of T2DM at 1(st) year following intensive lifestyle measures; recurrence and relapse rate bounced back in half of subjects at 4 years, thereby indicating that weight loss and glycemic control is difficult to maintain in the long term with lifestyle interventions. Same recurrence phenomenon was also observed with pharmacotherapy with rimonabant, sibutramine and orlistat. Bariatric surgery has been seen to associate with substantial and sustained weight loss in morbidly obese patients. Interestingly, bariatric surgeries also induce higher rates of short and long-term diabetes remission. Although the exact mechanism behinds this diabetes remission are not well understood; improved insulin action, beta-cell function and complex interplay of hormones in the entero-insular axis appears to play a major role. This article reviews the effectiveness of bariatric procedures on remission or improvement in diabetes and put a perspective on its implicated mechanisms.