When it comes to managing type 2 diabetes in overweight people, stomach-shrinking surgeries are still more effective than trying to shed pounds with pills and lifestyle changes, researchers said.
Three years into a US study that compares various approaches – gastric bypass, sleeve gastrectomy and simply trying medical counselling, diet, exercise and weight loss medications – the findings show that the two surgical procedures are still superior at reducing blood sugar and weight.
Researchers said their findings could provide a way to help the some 23 million American adults who have type 2 diabetes, most of whom are overweight or obese.
Fewer than half of adults with diabetes are able to get their blood sugar under control with medication, experts say.
The latest results from the largest randomised controlled trial of its kind were published in the New England Journal of Medicine and discussed at the American College of Cardiology annual meeting.
"Bariatric surgery was more effective than medical therapy in achieving glycaemic control with weight loss as the primary determinant of this outcome," said study author Sangeeta Kashyap, associate professor medicine at Cleveland Clinic Lerner College of Medicine.
"We concluded that bariatric surgery should be considered as a treatment option for the treatment of type 2 diabetes in patients who are moderately and severely overweight."
The research included 150 overweight people with uncontrolled diabetes that had persisted for at least eight years when they began the study, despite taking three or more medications.
Surgery groups did better
They were randomly assigned to undergo one of the two surgeries plus counselling, or simply expert therapy in health changes without surgery.
After three years, just 5% of patients who did not have surgery had achieved the desired level of glycaemic control, defined as a three-month average blood glucose level of 6% or lower.
That target is slightly more aggressive than the American Diabetes Association recommendation of 7%.
The surgery groups did much better, with 37.5% of gastric bypass and 24.5% of sleeve gastrectomy patients meeting the mark, after starting at an average blood sugar level of 9.2%.
Weight loss was five to six times greater in patients who had one of the surgeries.
No improvements in quality of life
The gastric bypass group lost on average a quarter of their body weight while the sleeve gastrectomy patients shed 21%. Those on medical therapy alone lost 4%.
Meanwhile, people who did not undergo surgery reported no improvements in quality of life, according to eight measures including body pain, general health, energy and fatigue.
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Gastric bypass patients reported five improvements and sleeve patients reported two. There were no major complications among those who underwent the surgeries.
Gastric bypass involves reducing the stomach to below three percent of its natural volume, then connecting a new gastric pouch that bypasses the stomach and goes straight to the intestine.
In sleeve gastrectomy, part of the patient's stomach is removed to reduce its volume by about 75%.
Gastric bypass best performer
Gastric bypass outperformed the sleeve gastrectomy in the study, which was funded by the National Institutes of Health, the Cleveland Clinic and Ethicon, a division of pharmaceutical giant Johnson and Johnson which sells surgical products for weight loss.
Amit Khera, associate professor at the University of Texas Southwest Medical Centre, who was not involved in the study, described the research as "important" because it addresses the longer-term benefits from surgery versus counselling and weight loss attempts alone.
"In the surgical arm, it does seem to be quite durable," he told reporters.
"Normalizing blood sugar seems to be retained at three years. That is a really important observation."
On the other hand, people who did not have surgery showed early improvements in their blood sugar, dropping close to the target of 7.5 in the first year.
But that group was back up to 8.4% in year three.
The study, called the Surgical Treatment and Medications Potentially Eradicate Diabetes Efficiently (STAMPEDE) trial, is designed to follow its patients for a total of five years.
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