Spotlight on bariatric surgery
Treatment of type 2 diabetes with bariatric surgery was discussed by several recent publications, including updated guidelines from a group of medical specialty organizations.
Treatment of type 2 diabetes with bariatric surgery was discussed by several recent publications, including updated guidelines from a group of medical specialty organizations.
The guidelines from the American Society for Metabolic and Bariatric Surgery, the American Association of Clinical Endocrinologists and the Obesity Society expanded the patient population eligible for surgery. Under the new recommendations, patients with diabetes or metabolic syndrome and a body mass index (BMI) of 30 kg/m2 or higher may be offered a bariatric procedure, although the guidelines note that “current evidence is limited” for patients with BMIs under 35. The previous version of the guidelines, from 2008, had found insufficient data to recommend bariatric surgery at a BMI under 35. The updated guidelines were published in the journals Surgery for Obesity and Related Diseases, Endocrine Practice and Obesity on March 26.
Evidence support for bariatric surgery in less obese patients was provided by a report of the Swedish Obese Subjects study. The study included more than 2,000 men and women who underwent bariatric surgery and about 2,000 obese controls receiving usual care. In this report, published in the May Diabetes Care, patients were divided into two groups: those traditionally eligible for bariatric surgery (BMI of 40 or above, or at least 35 with a comorbidity) and noneligible (BMI below 35, or between 35 and 40 with no comorbidities). After up to 20 years of follow-up, researchers found that diabetes incidence was reduced a similar amount (compared to controls) in both the eligible and noneligible groups (73% vs. 67%), leading the study authors to conclude that BMI is not the best criteria for eligibility and that some patients who could benefit from surgery are being excluded.
On the other hand, a very small study of diabetic obese patients undergoing Roux-en-Y gastric bypass found that patients could potentially see as much benefit from caloric restriction as surgery. The 10 study participants first were admitted for 10 days and given a standard liquid preoperative diet, with their glucose measured every four hours. After at least six weeks of washout, they had the surgery, followed by another 10 days of the same liquid diet and glucose measurement. The results, published by Diabetes Care on March 25, showed that patients lost more weight (7.3 kg vs. 4.0 kg) and had lower glycemia (1,293.58 mg/dL per day vs. 1,478.80 mg/dL, reported as area under the curve for daily average capillary glucose measurements) during the presurgery period. The authors speculated the slight difference in overall glycemia is due to the surgery-related stress response. They concluded that “nonsurgical interventions that successfully achieve and maintain such strict caloric restriction have the potential to resolve diabetes to a comparable degree as RYGB.”