In a recent study published in the journal JAMA Surgery, a team of researchers discovered that obese patients with type 2 diabetes who underwent weight loss surgery along with two years of low-level lifestyle intervention experienced a higher rate of disease remission than lifestyle intervention alone. The findings add to an increasing body of scientific evidence that weight loss surgery is beneficial to treating type 2 diabetes in obese patients.
It remains unclear how exactly weight loss surgery (also known as bariatric surgery) impacts type 2 diabetes. However, it has been established that nonsurgical treatments alone have not generally resulted in substantial improvement of diabetes or its potential long-term complications. As demonstrated in many observational studies and several small randomized clinical trials (RCTs) of short duration, type 2 diabetes is greatly improved after bariatric surgery. In a recent study, for example, it was determined that the loss of weight from the use of gastric banding directly improves diabetes in patients.
However, researchers feel it is important to understand the longer-term effectiveness and risks of all types of bariatric surgical procedures in comparison to lifestyle and medical management for those with type 2 diabetes and obesity who are seeking medically supervised weight loss.
How Weight Loss Surgery Reduces Type 2 Diabetes Compared To Non-Surgical Techniques
To address this issue, in their study titled “Three-Year Outcomes of Bariatric Surgery vs Lifestyle Intervention for Type 2 Diabetes Mellitus Treatment: A Randomized Clinical Trial,” Anita P. Courcoulas, M.D., M.P.H., of the University of Pittsburgh Medical Center along with colleagues conducted a 3-arm randomized clinical study assessing 3 years after treating 61 participants with obesity aged between 25 and 55 years with Type 2 Diabetes Mellitus (T2DM).
Participants were subject to randomization to receive a lifestyle weight loss intervention for one year and then a low-level lifestyle intervention for two years or were subject to randomization to undergo surgical treatments (Roux-en-Y gastric bypass [RYGB] or laparoscopic adjustable gastric banding [LAGB]) and then low-level lifestyle intervention in years 2 and 3.
Results revealed that after three years body mass index was less than 35 for 43% of the participants. Results also revealed that complete or partial type 2 diabetes remission was achieved by 40% of RYGB, and 29% of LAGB, while none of the participants that received intensive lifestyle weight loss intervention achieved remission.
The use of medication for diabetes was even more reduced in the surgical groups in comparison to the lifestyle intervention-alone group, with results showing that 65% of RYGB and 33% of LAGB went from using insulin or an oral medication at baseline to no medication at year 3, while none of the participants in the intensive lifestyle weight loss intervention achieved reduction of diabetic medication use.
Average reductions in percentage of body weight after 3 years were the greatest after RYGB at 25% (2%), followed by LAGB at 15% (2%) and lifestyle treatment at 5.7% (2.4%).
“Those who underwent a surgical procedure followed by low-level lifestyle intervention were significantly more likely to achieve and maintain glycemic control than were those who received intensive and then maintenance (low-level) lifestyle therapy alone, regardless of obesity class. More than two-thirds of those in the RYGB group and nearly half of the LAGB group did not require any medications for T2DM treatment at 3 years,” the authors said according to a recent news release.
“This study provides further important evidence that at longer-term follow-up of 3 years, surgical treatments, including RYGB and LAGB, are superior to lifestyle intervention alone for the remission of T2DM in obese individuals including those with a BMI between 30 and 35. While this trial provides valuable insights, unanswered questions remain such as the impact of these treatments on long-term microvascular and macrovascular complications and the precise mechanisms by which bariatric surgical procedures induce their effects.”
In a related commentary, Michel Gagner, M.D., F.R.C.S.C., F.A.S.M.B.S., of Florida International University, Miami, wrote according to the news release: “We should consider the use of bariatric (metabolic) surgery in all severely obese patients with T2DM and start a mass treatment, similar to what was done with coronary artery bypass graft more than 50 years ago.”