Introduction: Roux-en-Y gastric bypass has been proven to be beneficial for patients with obesity and type 2 diabetes mellitus (T2DM). In less-obese patient (BMI 30-35 kg/m2), surgical treatment is indicated when medication fails to control the T2DM. Asian develops diabetes at a lower BMI. For lower-BMI patients, the rate of diabetes amelioration varies significantly with patients of higher BMI after surgical treatment. The factors that contribute to the post-operative diabetes response rate in lower-BMI patients have not been elucidated.
Methods: Between 2010 and 2014, a total of 144 patients who underwent gastric bypass for the treatment of T2DM were included for study. Patients were divided into two groups for subgroup analysis, namely BMI > 30 kg/m2 and BMI < 30 kg/m2. Factors affecting the remission rate were examined.
Results: Of the studied patients, the DM remission rate for the high-BMI group (BMI > 30 kg/m2) was 80% (n = 90) whereas for the lower BMI (BMI < 30 kg/m2) was 50% (n = 54), p < 0.001. For high-BMI group, low HbA1c and high fasting C-peptide are predictive factors whereas for lower-BMI group, along with elevated C-peptide level, disease duration is the positive predictive factor for DM remission.
Conclusion: Patients with BMI > 30 kg/m2 and those with BMI < 30 kg/m2 have distinct remission predicting factors. Low HbA1c is a predictor of remission in low-high-BMI patients while duration of diabetes is for high-low-BMI patients. C-peptide is a predictor of remission in both groups. Further large-scale studies are required to define the predictors of diabetes remission after gastric bypass in low- and high-BMI patients.
Keywords: Gastric bypass; Obese; Predictive factors; Type 2 diabetes.