Bariatric surgery is very effective in reducing the long-term incidence of type 2 diabetes in obese individuals, according to a study published in the New England Journal of Medicine (2012;367:695-704).
Lena M.S. Carlsson, MD, PhD, of the University of Gothenburg in Sweden, and colleagues compared the rates of type 2 diabetes in 1,658 patients who underwent bariatric surgery and 1,771 obese matched controls who received usual care. None of the patients had diabetes at baseline; they ranged from 37-60 years old; and all had a body mass index (BMI) of at least 34 kg/m² for men and 38 kg/m² for women.
During up to 15 years of follow-up, the researchers found that type 2 diabetes developed in 392 control patients but only 110 bariatric surgery patients (incidence rate, 28.4 versus 6.8 per 1,000 person-years; adjusted hazard ratio for bariatric surgery, 0.17). The presence or absence of impaired fasting glucose had a significant impact on the effect of bariatric surgery, but BMI did not. Postoperative mortality was 0.2%, and 2.8% of bariatric surgery patients required additional surgery due to complications.
“Our data indicate that bariatric surgery has a preventive effect on incident type 2 diabetes, particularly in participants with impaired fasting glucose,” Dr. Carlsson and colleagues concluded. “Baseline BMI did not influence the preventive effect of bariatric surgery on type 2 diabetes, implying that anthropometric data are not useful in the selection of candidates for bariatric surgery, whereas data on impaired fasting glucose may be helpful.”