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Almost three in every four obese people suffering from diabetes can be cured of the disease with bariatric surgery, according to a groundbreaking new study, one that some experts say opens the door to changes in treatment of diabetes as profound as the discovery of insulin.
Researchers found that 73 per cent of patients whose stomachs were shrunk with the simple surgical procedure were cured of Type 2 diabetes.
By contrast, only 13 per cent of diabetics who followed conventional therapy - dieting, weight loss and medication - went into remission.
John Dixon, head of clinical research at the Centre for Obesity Research and Education at Monash University in Melbourne, Australia, and lead author of the paper, stressed that obese patients saw their diabetes disappear when they lost significant amounts of weight.
Those who underwent bariatric surgery did so far more effectively. They lost, on average, 20.7 per cent of their body weight (about 21 kilograms) and their average waist size shrunk 18 centimetres, while those who made lifestyle changes lost a modest 1.7 per cent of their weight (a mere 1.5 kilograms) and saw their waist size decrease 4 centimetres over the two-year study period. The patients at the start of the study weighed, on average, 105 kilograms and had a waist circumference of 115 centimetres.
"Intensive weight-loss therapy may be a more effective first step in the management of diabetes than simple lifestyle change," Dr. Dixon said. He added that the study is continuing, to check if the weight-loss and health benefits are maintained over the long term.
David Lau, president of Obesity Canada and chairman of the Diabetes and Endocrine Research Group at the University of Calgary, said the new research is "very important" and should get physicians and policy-makers rethinking their approach to the epidemic of diabetes.
"It's clear that bariatric surgery is one of the best ways to treat and prevent diabetes," he said. "But unfortunately, in Canada, we're not ready for prime time."
Dr. Lau noted that Canada has few surgeons able to do bariatric surgery and that some provinces, such as Ontario, refuse to cover the cost of the procedure despite its demonstrable benefits.
In the United States, about 170,000 bariatric operations are performed annually. In Canada, only a few thousand procedures are done each year because of limited funds and restricted access to surgical time.
The study, details of which are published in today's edition of the Journal of the American Medical Association, involved 60 diabetics whose body mass index (an approximation of body fat) was between 30 and 40. (An adult with a BMI of 30 or higher is considered obese.)
They were randomly assigned to one of two groups - surgery or conventional therapy.
After two years, 26 patients who underwent Lap-band surgery - using a plastic band to transform the stomach into a small pouch - were free of diabetes symptoms. Only four of the patients who underwent conventional therapy were free of symptoms.
In an editorial also published in JAMA, David Cummings of the department of medicine at the University of Washington in Seattle, said that using surgery to treat diabetes may be the most profound change in approach since the discovery of insulin.
He said that while the Australian researchers used a simple Lap-band method, another form of bariatric surgery, called Roux-en-Y gastric bypass, could potentially have more dramatic results. That is because the method, in which the stomach and part of the intestine is bypassed, triggers hormonal changes that also benefit diabetics.
"It may be time to view bariatric operations ... as interventions about which all obese patients with diabetes should be informed and given access," Dr. Cummings said.
About two million Canadians suffer from diabetes, according to the Canadian Diabetes Association. There are three distinct forms: Gestational diabetes is a temporary condition that occurs during pregnancy; Type 1 diabetes, usually diagnosed in children, occurs when the pancreas is unable to produce insulin; Type 2 diabetes, which accounts for 90 per cent of cases, occurs when the pancreas does not produce enough insulin or the body does not effectively use the insulin it produces.
While there is a genetic underpinning to diabetes, Type 2 is principally a lifestyle disease - the condition develops when people are overweight and inactive.
How the Lap-band works
The band used in this bariatric study is surgically placed around the top of the stomach. Part of the stomach is stitched over it to hold the device in place, while the access port is secured closer to the skin.
Once the Lap-band is in place, a saline solution can be injected into the access port. The fluid travels along the silicone tubing, then fills the circular inflation membrane, making the band tighter.
This constricts the stomach opening, and reduces the amount of space inside, giving the patient an earlier feeling of fullness, limiting food consumption. The band's tightness can be adjusted by adding or removing saline through the access port, according to the patient's needs. This system allows for long-term, non-surgical adjustability.
SOURCE: BIOENTERICS CORPORATION
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