March 9, 2018
Lifestyle changes — like fitting more activity into your day and eating more nutritious, high-fiber foods — have long been recommended for people diagnosed with type 2 diabetes to aid in weight loss and blood sugar control. For people with type 2 diabetes who are obese, there’s also the option of gastric bypass surgery.
If you fall into the latter category, gastric bypass may indeed be a good choice: A randomized trial suggests that the procedure may be more effective for long-term weight loss than simply changing your diet or lifestyle.
Published in the February 2018 issue of Diabetes Care, the study found that after three years, obese participants who underwent gastric bypass lost an average of nearly 55 pounds (lb) compared with those in the weight management group, who lost just 11 lb. The gastric bypass group also saw their A1C (a measurement of average blood sugar levels over two to three months) and cardiometabolic risk factors (like blood pressure and triglycerides) improve more, as well as quality-of-life factors like self-esteem. They were also able to use fewer diabetes, blood pressure, and cholesterol medications.
How Study Authors Carried Out the Research
In the study, researchers used a specific type of bypass called Roux-en-Y gastric bypass (RYGB), which is a surgery done to reduce the size of the upper stomach. One group received the surgery, while the other took part in a medical diabetes- and weight-management program, wherein they adjusted their medications to help enhance weight loss, changed their diets, exercised, and took educational classes.
Fewer than 10 percent of patients could keep weight off with lifestyle changes alone, the authors reported in their research. But it’s not really the weight loss that’s the major focus of the study. “Yes, there are differences in weight loss, but the key question that emerged from this and other studies like it is that control of diabetes is much better in the long term in patients who are randomized in gastric bypass surgery,” says Mary-Elizabeth Patti, MD, an adult endocrinologist at Joslin Diabetes Center in Boston. Dr. Patti is not an author on this research but is currently working with the team to investigate the long-term outcomes of these therapies.
While just 11 percent in the weight-management group achieved the target A1C of under 7 percent (considered normal), 58 percent of those in the RYGB group did.
Although weight loss may help to maintain blood sugar control, it’s only part of the equation. Gastric bypass surgery changes the route that food travels in your digestive system. “It goes from your esophagus to a small stomach pouch that empties into a loop of the intestine, which normally doesn’t see food that really hasn’t been digested yet,” Patti explains. After that, the intestine secretes hormones that stimulate insulin production in the pancreas. Insulin is a hormone that helps regulate blood sugar levels, and people with type 2 diabetes have a condition called insulin resistance, leading to high blood sugar (hyperglycemia).
What the New Findings Bring to the Table
This study adds to the conversation around gastric bypass for diabetes because it was a randomized trial in which patients didn’t pick their treatment.
Previous observational studies focused on patients who chose surgery or medical therapy, which adds confounding factors into the mix, says Patti. (One group may be ready to make a change, or one may be more risk averse.) What’s more, she points out that since this study, a newer group of diabetes medications have come out that could change the results in the medical therapy group, but that’s something researchers don’t know.
What You Should Take Away From the Study if You’re Obese and Have Type 2 Diabetes
It’s clear that, as valuable as lifestyle changes are, they can be tough to implement. “It’s difficult to adhere to intensive lifestyle modification for a long period of time. We also know that as someone starts losing weight successfully, the body does adapt, slowing the metabolism, and therefore making it harder to continue to lose the weight,” says Reshmi Srinath, MD, an assistant professor and the director of the weight and metabolism management program at the Icahn School of Medicine at Mount Sinai in New York City, who was not involved in the study.
Dr. Srinath adds that while current criteria for bariatric surgery include having a BMI over 40 or over 35 with associated diseases like diabetes, this study suggests that surgery can be beneficial for people with milder obesity and uncontrolled diabetes.
For more people with type 2 diabetes, gastric bypass may be an option. “A number of different studies show that the earlier in the course of type 2 diabetes that bariatric surgery is performed, the more effective it is. Don’t wait until you can’t control it anymore,” says Patti. Of course, surgery is a difficult decision, and one you should make after speaking with your doctor and endocrinologist about the risks and benefits for you.
“This study is further evidence that clinicians should consider bariatric surgery as a treatment for those with uncontrolled diabetes and obesity. We know from prior research that surgery can help induce remission of diabetes. But we tend to hesitate on referring for surgery, and this study supports aggressive use of weight loss surgery to treat diabetes,” adds Srinath.
Of course, gastric bypass surgery is not a cure-all. “Surgery isn’t a quick fix. It needs to be considered with a lot of thought and discussed with your healthcare team,” says Patti. “It’s not the right answer for everyone.”