Severely obese individuals in the United States who underwent Roux-en-Y gastric bypass (RYGB) averaged a 27% weight loss 12 years later, with only a 3% incidence of type 2 diabetes mellitus and a 51% rate of diabetes remission, according to the results of a large multicenter observational prospective study.
In striking contrast, patients who did not undergo bariatric surgery averaged a 1%-2% weight loss at 12 years, a 26% incidence of diabetes, and only a 5%-10% rate of diabetes remission, said Ted D. Adams, PhD, of the University of Utah, Salt Lake City, and his associates. RYGB surgery also conferred substantial and statistically significant improvements long-term improvements in systolic hypertension and lipid levels, the researchers reported in the New England Journal of Medicine (2017 Sep 20. doi: 10.1056/NEJMoa1700459).
Dr. Ted D. Adams
“The follow-up rate exceeded 90% at 12 years,” the researchers wrote. Two years after undergoing Roux-en-Y gastric bypass, patients had lost an average of 45 kg (95% confidence interval, 43-47 kg). By postoperative year 6, they had regained an average of 9 kg (average loss from baseline, 36 kg; 95% CI, 34-39 kg). But they typically gained only about 1.3 kg more between years 6 and 12, and they had about a 92% lower odds of developing diabetes mellitus, compared with individuals who did not undergo bariatric surgery (odds ratio, 0.08; P less than .001). “Remission of type 2 diabetes was much more likely if the Roux-en-Y gastric bypass occurred before [patients began] treatment with insulin, presumably owing to the ability of partially viable beta cells to improve their function,” the researchers noted.
Funders included the National Institute of Diabetes and Digestive and Kidney Diseases, the National Center for Research Resources, Weill Cornell Medicine, and Intermountain Healthcare. Dr. Adams reported having no relevant conflicts of interest. One coinvestigator disclosed royalties from licensing a questionnaire on weight loss and quality of life, and another coinvestigator disclosed fees for services rendered during a trial of an intragastric balloon. The remaining researchers had no relevant disclosures.