OBJECTIVETo investigate the improvement of islet β-cell function after sleeve gastrectomy with ileal interposition duodenojejunal bypass operation in non-obese type 2 diabetes mellitus.

METHODSClinical data of 54 non-obese type 2 diabetes mellitus cases undergoing sleeve gastrectomy with ileal interposition duodenojejunal bypass operation in our hospital from March 2009 to October 2011 were retrospectively analyzed. Fasting glucose, glycosylated hemoglobin(HbA1c), fasting insulin, body mass index(BMI), insulin resistance index(HOMA-IR), homeostasis model β-cell function(HOMA-β), early phase insulin secretion index (DelteI30/DelteG30) and area under curve of insulin(AUCINS) were measured before operation, and 1, 3, 6, 12, 24 months after operation with standard oral glucose tolerance test(OGTT).

RESULTSAt 24 months after operation, HbA1c decreased from preoperative (8.2±0.8)% to postoperative (6.3±0.1)%(P<0.01), as did the fasting glucose [(9.2±0.6) mmol/L vs. (5.9±0.5) mmol/L, P<0.01] and HOMA-IR (2.1±0.6 vs. 0.8±0.3, P<0.01). The postoperative BMI was not significantly different from the preoperative level. HOMA-β increased (28.4±9.2 vs. 56.3±12.8, P<0.05). DelteI30/DelteG30 increased after surgery (0.8±0.2 vs. 1.8±0.7, P<0.01). AUCINS was (42.6±17.1) mIU/L, (31.5±18.6) mIU/L, (34.71±12.9) mIU/L, (49.2±16.3) mIU/L, (78.3±21.7) mIU/L, (74.8±15.2) mIU/L before operation and at postoperative 1 month, 3 months, 6 months, 12 months, 24 months, respectively, indicating an increase in AUCINS 6 months later. Linear correlation analysis showed that HbA1c was negatively correlated with HOMA-β, DelteI30/DelteG30 and AUCINS (r=-0.628, P<0.01; r=-0.571, P<0.01; r=-0.606, P<0.01), and positively correlated with HOMA-IR (r=0.784, P<0.01).

CONCLUSIONSSleeve gastrectomy with ileal interposition duodenojejunal bypass can improve islet β cells function. It plays an important role in the surgical treatment of diabetes.