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.