Serum free fatty acid levels and insulin resistance in patients undergoing one-anastomosis gastric bypass

Introduction One anastomosis gastric bypass (OAGB) leads to improvement in glucose homeostasis; however, the mechanism of this beneficial effect is not fully understood. Increased serum free fatty acid (FFA) concentrations in obese subjects contribute to the development of insulin resistance and type 2 diabetes. Aim The authors hypothesized that improvement in glucose homeostasis after OAGB may be associated with a decrease in FFA concentration. Material and methods Serum FFA levels were measured by gas chromatography-mass spectrometry before and 3 months after OAGB and, for comparison, in patients who underwent laparoscopic sleeve gastrectomy (LSG). Serum insulin was assayed by immunoenzymatic method, and other parameters by standard laboratory methods. Results OAGB resulted in a large decrease in FFA levels and great improvement in insulin sensitivity. These effects in patients after LSG were less prominent. Conclusions Results suggest that decreased serum FFA levels after OAGB contribute to resolution of insulin sensitivity after this type of bariatric surgery.