ASMBS: Bariatric Surgery Found Superior to Drugs in Controlling Diabetes

By Todd Neale
WASHINGTON, 19 june 2008-- For morbidly obese patients with type 2 diabetes, bariatric surgery led to more improvement in glycosylated hemoglobin than standard treatment, a retrospective analysis showed. Those who underwent Roux-en-Y gastric bypass had an average drop in hemoglobin A1c of 21% within a year (P<0.001), compared with an increase of 11% with conventional treatment (P<0.05), which included oral hypoglycemics and insulin, according to Daniel Mumme, M.D., of Gundersen Lutheran Medical Center in La Crosse, Wis. Body mass indices fell from an average of 47.3 to 30.9 kg/m2 (P<0.05) in the surgery group and did not change significantly from 44.9 kg/m2 in the conventional-treatment group, he reported at the American Society for Metabolic & Bariatric Surgery meeting here.
"The data continue to support the effectiveness of bariatric surgery in treating type 2 diabetes in morbidly obese patients," Shanu Kothari, M.D., also from Gundersen Lutheran and senior author of the study, said.
"I think clinicians need to strongly consider laparoscopic gastric bypass surgery as a first-line treatment option for morbidly obese type 2 diabetics," he said.
The American Diabetes Association recommends keeping HbA1c levels below 7%. To evaluate the ability of bariatric surgery to meet this goal, the researchers retrospectively analyzed Gundersen Lutheran's prospective bariatric database and identified 53 morbidly obese patients (79% female) with type 2 diabetes who had undergone laparoscopic gastric bypass from 2001 through 2006.
For comparison, they identified 53 age- and sex-matched patients with medically managed diabetes from their institution's family practice database. The mean age of the patients was 48.
In the surgery group, HbA1c levels decreased from a mean of 7.5% pre-surgery to 5.8% after one year, settling at 6.1% after three years (P<0.001), below the ADA recommended level.
In those who received conventional treatment, the levels increased from a mean of 7% at baseline to 7.8% after three years (P<0.05).
In addition to lowering HbA1c levels, surgery also resulted in less need for oral medications or insulin. Before surgery, 84.3% of the patients were taking medication and a year after surgery only 22.4% still needed it (P<0.05).
In the conventional-treatment group, however, the percentage of patients who needed medication or insulin increased from 66.7% to 82% at one year (P<0.05).
Dr. Kothari said that losing weight through nonsurgical means might yield the same benefits but that these patients have a low probability of shedding substantial pounds and keeping them off without bariatric surgery.
"It just doesn't happen," he said.
One of the biggest hurdles to getting the surgery, he said, is cost, because patient requests are often met with insurance denials and unrealistic insurance prerequisites, such as requiring the patient to have their weight recorded by a physician weekly for a year. Bariatric surgery should be universally covered, he said.
For controlling diabetes, "if there was a pill on the market that did what we do with our scalpel, it would be malpractice not to offer it to your patients," he said.
He noted that it might not simply be the weight loss reducing the patients' HbA1c levels following gastric bypass, suggesting that a hormonal manipulation might occur when the duodenum and part of the small intestines are bypassed.
"Whether that's just due to reduced caloric intake at that time or there is a hormonal component is an area of ongoing research," he said.
He concluded, "I think it's safe to say that maximum medical management of the morbidly obese diabetic patient with insulin and oral hypoglycemics is ineffective based on this study."
The study was funded by the Gundersen Lutheran Medical Foundation. The authors reported no conflicts of interest.
Primary source: American Society for Metabolic & Bariatric SurgerySource reference:Mumme D, et al "Impact of laparoscopic Roux-en-Y gastric bypass on HGA1C concentrations in patients with diabetes: a matched cohort analysis" ASMBS Meeting 2008; Abstract PL-05. Additional Diabetes Coverage
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