Preventing type 2 diabetes in obese persons is more efficient with bariatric surgery than usual care, according to a study released on Aug. 22 in The New England Journal of Medicine.

Overall results from the study, which looked at 1,658 non-diabetic patients who experienced bariatric surgery and 1,771 non-diabetic obese persons in a control group over a period of up to 15 years, showed bariatric surgery reduced long-term occurrence of type 2 diabetes in obese patients by 78 percent. Data showed an incidence rate of type 2 diabetes development in a control group to be 28.4 cases per 1000-person years (392 participants), while the incidence rate within the group that underwent bariatric surgery was only 6.8 cases per 1000 person-years (110 participants) [risk-adjusted HR with bariatric surgery, 0.17; 95 percent CI, 0.13—0.21]. The study also revealed that bariatric surgery effects were not influenced by body mass index (BMI), but instead by the presence or absence of impaired fasting glucose. Patients with impaired fasting glucose saw a decrease in risk of type 2 diabetes by 87 percent following bariatric surgery. According to the study authors, "this risk reduction is at least twice as large as that observed with lifestyle interventions in moderately obese, pre-diabetic persons." However, the authors noted that the lack of BMI influence on prevention implies that "anthropometric data are not useful in the selection of candidates for bariatric surgery."