Bariatric surgery can reverse type 2 diabetes in severely obese people, reducing or eliminating the need for medications, and improve other serious health problems such as high blood pressure and sleep apnea, but it still remains to be determined which patients with type 2 diabetes will benefit most from surgery.
Do individuals who are moderately obese also benefit from surgery? And what is the duration of improvement in diabetes after surgery? Is it lifelong? Does having surgery change the risk of complications from diabetes?
Those are precisely the kinds of questions that a new study known as ARMMS-T2D (Alliance of Randomized Trials of Medicine versus Metabolic Surgery in Type 2 Diabetes) will tackle over the next five years, thanks to an award from the National Institutes of Health (NIH).
The research is being conducted at institutions in the ARMMS-T2D consortium, composed of Cleveland Clinic, Joslin Diabetes Center, University of Pittsburgh and the University of Washington. The coordinating center is Cleveland Clinic.
The ARMMS-T2D study is a follow-up effort from four smaller-scale, randomized controlled trials conducted at these institutions, including SLIMM-T2D (Surgery or Lifestyle with Intensive Medical Management in the Treatment of Type 2 Diabetes) conducted by Joslin and Brigham and Women's Hospital.
The SLIMM-T2D study examined whether gastric surgery (both band and bypass) or an intensive program of medical and lifestyle management (Why WAIT?) is more effective for the treatment of type 2 diabetes in overweight or mildly obese patients with type 2 diabetes. Data from this study have demonstrated that surgery is more effective in controlling diabetes than medical and lifestyle management, but longer-term information is needed.
Now, investigators from the four centers have merged data and outcomes measures from their individual clinical trials into a unified, prospective observational study that will continue to follow this unique cohort of patients, individuals previously randomized to bariatric surgical procedures or medical and lifestyle intervention.
The unique design of ARMMS T2D will provide the largest body of long-term evidence to guide practicing doctors in clinical decision making regarding the durability, efficacy, and safety profile of both treatment groups. The long-term complications and benefits are unknown because this has never been studied over a long period of time in a randomized study.
Mary-Elizabeth Patti, M.D., F.A.C.P., Director of the Hypoglycemia Clinic at Joslin Diabetes Center, is the Principal Investigator at Joslin. Over the next five years, her study team will follow up with participants at different points to take blood samples and look for new patterns in hormone secretion and improved metabolism.
"The four centers came together so we could pool the studies to get more information about how surgery changes metabolism in the long-term," says Dr. Patti. "We know that's the case in the short run, and that it's better than medical management alone, but we want to understand how surgery controls diabetes and if it does so for the long-term."
The study will include approximately 242 patients with type 2 diabetes. More than one third of these individuals have a BMI less than 35.
The study will identify the factors that result in a higher rate of long-term diabetes remission, better blood sugar control and rate of diabetes relapse after initial remission.
There is an unmet need for patients to achieve good glucose control safely, says Dr. Patti. "This study will better define who is likely to respond to gastric surgery and help answer the question, when during the course of type 2 diabetes does surgery have the greatest benefit? There's evidence that the earlier, the more effective it is. So if you wait until someone has had diabetes for 30 years it might not be as helpful."