An FAQ with Rohit Soans, MD
Bariatric surgery isn’t simply about achieving weight loss or improving appearance. One somewhat surprising benefit of this surgery is that it achieves long-term control of diabetes in a significant percentage of patients with non-insulin-dependent diabetes mellitus.
Given the potential comorbidities of type 2 diabetes and its overall health risks, bariatric surgery may be an option to consider in obese patients with the condition. Best Practice spoke with Rohit Soans, MD, Director of Metabolic and Bariatric Surgery at Temple University Hospital, about obesity, bariatric surgery, and how surgery may eliminate diabetes.
What percentage of patients with diabetes no longer have the condition after bariatric surgery?
ANSWER: Between 75 and 95 percent of patients with diabetes see improvement or complete resolution of their condition after bariatric surgery. A 2009 study in the American Journal of Medicine showed that diabetes was improved or resolved in 86 percent of patients, with 78 percent achieving complete resolution of their diabetes. In a 2014 meta-analysis in JAMA Surgery, 86 to 92 percent of patients achieved resolution.
Does bariatric surgery lower the risk for diabetes-related complications like diabetic retinopathy, diabetic neuropathy, and diabetic nephropathy?
ANSWER: A recent study in the Annals of Internal Medicine found that bariatric surgery was associated with half the incidence of microvascular disease at five years, compared with typical medical care. A lowered incidence of neuropathy was the primary reason, but benefits were seen with retinopathy and nephropathy as well.
Should bariatric surgery be considered as an early intervention for diabetes?
ANSWER: There is increasing evidence to make the case for utilizing bariatric surgery early in the course of diabetes. Multiple studies have demonstrated that patients who receive surgery sooner after their diabetes diagnosis show increased rates of improvement and resolution of their hyperglycemia.
Are positive effects seen in the mildly obese as well as morbidly obese?
ANSWER: A randomized clinical trial published in the New England Journal of Medicine showed that the mildly obese, managed with surgery and medication, saw their A1c levels lowered by about 1.8 percentage points more than those who received only medical management. Bariatric surgery was also more effective than medical therapy for lowering both lipid levels and daily medication use in these patients. The benefits were shown to be long term and durable.
Do different types of bariatric surgery affect the outcome for patients with type 2 diabetes?
ANSWER: According to a 2015 study in JAMA Surgery that looked at population-based data, gastric bypass and sleeve gastrectomy had a greater chance for remission of type 2 diabetes compared with gastric banding.
What is the mechanism that causes remission of type 2 diabetes after bariatric surgery?
ANSWER: Type 2 diabetes is a complex metabolic disease. Obesity is a strong risk factor, but bariatric surgery seems to affect patients beyond the effect of the weight loss from surgery itself. Several studies have shown that after gastric bypass, diabetes is in remission within days, before much weight loss has happened. While we do not yet fully understand how bariatric surgery exerts its metabolic effects, it seems to increase insulin sensitivity and reduce inflammation and lipotoxicity.