Bariatric surgery did more to improve symptoms of diabetes, high blood pressure and high cholesterol after three years than intensive treatment with drugs alone, according to new results from a closely watched clinical trial involving patients who were overweight or obese.

Study participants who had gastric bypass surgery or sleeve gastrectomy also lost more weight, had better kidney function and saw greater improvements in their quality of life than their counterparts who did not go under the knife, researchers reported Monday.

The latest findings from the trial, known as STAMPEDE — for Surgical Treatment and Medications Potentially Eradicate Diabetes Efficiently — should prompt more patients with Type 2 diabetes to consider surgery as a viable treatment, even if their body mass index isn’t high enough for them to qualify as severely obese, said Dr. Philip Schauer, director of the Cleveland Clinic’s Bariatric and Metabolic Institute and leader of the trial.

“Right now, bariatric surgery is way underutilized,” Schauer said. “I wouldn’t say that every diabetic needs bariatric surgery. But I would say there are a lot of patients on aggressive medical treatment that are looking at some surgery down the road — including extremely costly interventions such as amputations and coronary bypass procedures.”


Bariatric surgery, including the two procedures tested in the STAMPEDE trial, can cost as much as $60,000, depending on complications. That price tag has prompted skepticism among insurers about its worth as a diabetes treatment. But it “seems like a bargain” compared with the future surgical costs many of the 17 million Americans with Type 2 diabetes will face if they cannot get their blood sugar under control, Schauer said.

The trial results were presented Monday at a meeting of the American College of Cardiology and the American Heart Assn. in Washington, and published by the New England Journal of Medicine.

The study randomly assigned 150 overweight and obese people with Type 2 diabetes to one of three groups. Those in the control group had their diabetes managed with medications and daily blood-glucose monitoring. They also received intensive counseling about diet and exercise, including regular weigh-ins to monitor their progress. After three years, they had lost an average of 9.5 pounds.

The second group in the trial got Roux-en-Y gastric bypasses, in which the stomach is reshaped and relocated to divert most food past much of the lower intestine, where nutrients and calories are largely absorbed. The third group got a procedure called sleeve gastrectomy, which staples some 80% of the stomach closed, creating a banana-shaped tube where once a large pouch existed. Patients who had surgery received intensive medical management and lifestyle counseling as well.


Three years later, those who had the Roux-en-Y bypass had lost an average of nearly 58 pounds, and those who had sleeve gastrectomy lost an average of 47 pounds.

More importantly, Schauer said, the patients in the surgery groups were much more likely to have their diabetes under control — 58% of those who had Roux-en-Y and 33% of those who had sleeve gastrectomy were able to stop taking diabetes medications. Only 5% of patients in the control group achieved the same endpoint after three years, and none were able to discontinue medications completely.

In addition, study volunteers who had gastric bypass whittled their daily number of blood pressure and cholesterol-lowering medications from 2.73 to 0.96, on average. And subjects who had sleeve gastrectomy reduced their average number of cardiovascular medications from 2.18 to 1.35 three years later.

The medication tally for the control group didn’t budge.


Ultimately, Schauer said, better health should afford patients a fuller, happier life — and by that measure too, bariatric surgery yielded superior results.

The Roux-en-Y subjects showed greatest improvement in quality of life, including measures of bodily pain, physical functioning, general health, emotional well-being, and energy and fatigue. Those who got the sleeve gastrectomy also reported more significant improvements than those in the control group.

Schauer noted that some of the patients who benefited from bariatric surgery did not have a body mass index high enough to qualify for the procedure under most clinical guidelines and insurance plans. More than one-third of the volunteers enrolled in the trial had a body mass index between 27 and 34, below the usual threshold of 35.

But the overweight and mildly obese patients who got bariatric surgery showed health improvements on a par with much heavier diabetics, Schauer said.


“Hopefully, insurance policymakers will look at this data and consider expanding their coverage,” he said.

Randy Seeley, a University of Cincinnati professor of endocrinology who was not involved in the trial, said the latest results showed that both Roux-en-Y and sleeve gastrectomy worked “demonstrably better than standard diabetes interventions.”

But with its steep price, bariatric surgery is unlikely ever to be available to many who suffer from both obesity and diabetes, he said. Currently, about 1% of those who might benefit from such surgery are getting it, and even with a mighty effort to expand access, experts predict that figure is unlikely to rise above 4%.

“This highlights the need to understand the mechanistic similarities and differences” between the two procedures, “so that we might harness their efficacy to help more patients with diabetes,” Seeley said.


Last week, Seeley and colleagues from Denmark and Sweden published a study in Nature describing a key genetic switch that appears to be activated in sleeve gastrectomy, prompting changes in gut bacteria that improve metabolic function, appetite changes and weight loss. Someday, those changes might be induced without surgery, he said.

melissa.healy@latimes.com

Twitter: @LATMelissaHealy