People who underwent one of two stomach-reducing procedures were three to four times more likely to have their blood sugar drop to normal levels after one year of treatment compared with people who received intensive medical therapy alone.
Some people who had surgery got better so quickly that they were able to stop taking their diabetes medication before even leaving the hospital, says study head Philip Schauer, MD, director of the Bariatric and Metabolic Institute at the Cleveland Clinic.
They "were eventually weaned off all their diabetes medication -- as close to the definition of remission as you can get," Schauer tells WebMD.
"Bariatric [weight loss] surgery works and works well -- for both obesity and diabetes," Schauer says.
The findings were presented at the annual meeting of the American College of Cardiology and simultaneously published online by The New England Journal of Medicine.
About 80% of the 23 million American adults living with type 2 diabetes are overweight or obese.
High blood sugar is a major risk factor for a host of diabetes complications, including heart attack, amputation, kidney failure, and blindness.
In one recent study, 89% of people with type 2 diabetes who underwent gastric bypass surgery went into remission and 57% were still in remission after five years.
The new study, called STAMPEDE, involved 150 people -- two-thirds of whom were women -- with a body mass index (BMI) between 27 and 43. They were divided into three groups. Two groups received surgery: either gastric bypass, which surgically reduces the stomach size and reroutes food to bypass part of the small intestine; or sleeve gastrectomy, a procedure that surgically reduces the stomach by about 75%. Both procedures require about two or three days in a hospital and two to four weeks of recovery time.
The third group got intensive medical therapy for diabetes, which included various types of oral medications or injectables, including insulin.
Better Blood Sugar Control in Surgery Groups
At the start of the study, people had very high blood sugar, as measured by a test called hemoglobin A1c, or HbA1c. The average HA1c levels were 9.2% at the start of the study. An HbA1c level of 7% or lower is the traditional target for diabetes patients, but the study's goal was to reach a HbA1c level of 6% or less after one year.
Results showed that 42% of patients who underwent gastric bypass surgery achieved that goal, compared with 37% of patients who got the sleeve gastrectomy. Only 12% in the medication group reached that goal.
People who had surgery benefited in other ways, too. Their use of medications to lower blood pressure and cholesterol levels dropped, while use increased in people on intensive medical therapy. Not surprisingly, people getting surgery lost five times as much weight: about 55 to 64 pounds compared to 12 pounds in the medication group.