Weight-loss surgery can improve diabetes: studies
(Reuters Health) – Two small studies provide more evidence that weight-loss surgery may benefit people who are obese and have diabetes.
Both studies found that blood sugar levels were more likely to improve among people who were randomly assigned to have surgery than among those who went through intensive diet and lifestyle programs instead.
The studies included people on the lower end of the obesity spectrum, some of whom wouldn’t be recommended for surgery under current guidelines.
“In appropriate patients, this is something really worth considering,” said Dr. Allison Goldfine. She worked on one of the studies at the Joslin Diabetes Center and Harvard Medical School in Boston.
“There are multiple health issues that are related to type 2 diabetes,” she told Reuters Health, such as high blood pressure and cholesterol.
“It’s very important to address these issues to improve (people’s) health. I think this can be done through an intensive medical and weight management program, and I think this can be done through surgery,” Goldfine said. “One has to individually weigh the pros and cons.”
Obesity and diabetes are known to be closely linked. But there is a lack of long-term evidence on whether weight-loss surgery helps alleviate diabetes and related complications, researchers say, especially among people who are obese but not morbidly obese.
In one of the new studies, Dr. Anita Courcoulas from the University of Pittsburgh Medical Center and colleagues tracked 61 obese people with diabetes who were randomly assigned to undergo gastric bypass or gastric banding surgery or to complete a weight control program.
One year later, half of gastric bypass patients and about one-quarter of the gastric banding group had at least partial remission of their diabetes, meaning their blood sugar levels were closer to the normal range and they didn’t need diabetes medications.
No patients in the non-surgery group saw their diabetes go into remission.
In Goldfine’s study, researchers randomly allocated 38 patients – all obese, all with diabetes – to gastric bypass surgery or a group weight loss program.
One year later, 11 out of 19 gastric bypass patients met the goal for a drop in blood sugar levels. That compared to three out of 19 in the other group.
Both trials were published in JAMA Surgery.
The studies included people with a body mass index, or BMI, between 30 and 40 or between 30 and 42.
BMI measures weight in relation to height. For example, both a five-foot, six-inch person who weighs 186 pounds and a six-foot person who weighs 221 pounds have a BMI of 30.
The National Institutes of Health and other groups say weight-loss surgery is an option for people with a BMI of 40 or above who have no weight-related complications or a BMI of 35 or higher if they also have diabetes, sleep apnea or other problems.
Weight-loss surgery requires a drastic change in eating habits and can come with complications such as hernias, leakages and gallstones, as well as nutritional deficiencies.
“Right now people with lower BMIs would not typically be covered by insurance, but there is this growing body of data that potentially supports the use of these procedures” among people with diabetes and a BMI of 30 or above, Courcoulas said.
“It’s going to take putting several of these trials together in order to determine whether these recommendations should be moved,” Goldfine added.
She said that it’s important for people to consider surgery not just as a weight management issue, but as a diabetes management issue as well.
The trial results are in line with larger but less rigorously designed studies of people who decided on their own whether to get weight-loss surgery. That type of study can’t take into account all of the potential differences between people who do and do not have surgery, for instance that doctors might be more likely to refer healthier patients for the procedures.
Long-term results from one such study were published by Dr. Lars Sjostrom of Sahlgrenska University Hospital in Gothenburg, Sweden and colleagues this week in JAMA.
They followed 343 obese people with diabetes who decided to undergo one of three types of weight-loss surgery and another 260 who did not have surgery.
Two years later, 72 percent of the surgery patients had remission of their diabetes, compared to 16 percent of non-surgery patients. But diabetes returned in some of them, and 15 years after surgery, remission rates were down to 30 percent and seven percent, respectively.
Researchers say the small, randomized studies could set the stage for a larger trial comparing surgery and lifestyle interventions for diabetes. But challenges exist, such as recruiting enough participants who are willing to have their treatment randomly assigned.
Courcoulas told Reuters Health that for now, a more likely scenario is that data from multiple small trials will be combined into one larger analysis. Researchers will also keep following the current patients to see how they fare a few years after the treatments, she said.