Effect of bariatric surgery on glycemic profiles in multiethnic obese nondiabetic Asians.

Background: The effect of bariatric surgery on improvement and remission of type 2 diabetes (T2D) is well studied. The effect of surgery on glycemic profiles of obese, but nondiabetic individuals is unknown.

Objectives: We aimed to study changes in glycemic indices in obese nondiabetics undergoing bariatric surgery and correlate fat mass loss with changes in glycemic profiles.

Setting: University Hospital, Singapore.

Methods: A prospective database of nonT2D patients who underwent bariatric surgery between April 2009 and December 2014 was analyzed. Changes in weight, fat mass, and glycemic profiles, including glycated hemoglobin, C-peptide levels, and the homeostasis model assessment of insulin resistance were studied at 1- and 3-year follow-up.

Results: One hundred thirty-three nondiabetics underwent bariatric surgery in the study period. Twenty-nine (21.8%) patients were found to have impaired fasting glycemia. We observed reductions in mean fat mass from 47.4 ± 12.2 kg preoperatively to 27.8 ± 11.6 kg at 1 year. Despite mean fat mass regain to 33.9 ± 19.6 kg at 3 years, homeostasis model assessment of insulin resistance improved from severe insulin resistant state of >5.00 (7.13 ± 11.5) preoperatively to normal ranges of <3.00 (1.55 ± .91) at 3 years.

Conclusion: Bariatric surgery results in significant sustained weight loss in obese nondiabetics and normalizes glycated hemoglobin and homeostasis model assessment of insulin resistance after surgery. It is a promising modality to prevent or delay the onset of T2D in obese nondiabetic patients. Further studies should be conducted in nondiabetics to assess the efficacy of bariatric surgery in prevention of T2D onset in the longer term.