Effect of Gastrogastric Fistula Closure in Type 2 Diabetes

Roux-en-Y gastric bypass (RYGB) has been shown to significantly improve glucose control in patients with type 2 diabetes (T2DM). The formation of a gastrogastric fistula (GGF) allows nutrients to pass through the native route, rather than bypassing the duodenum in typical RYGB configuration. We sought to evaluate the effect of revisional bariatric surgery for known GGF on control of diabetes.

A retrospective chart review of a single academic institution was performed to identify patients who had T2DM at the time of corrective surgery for a GGF. Baseline characteristics, and postoperative outcomes including changes in body mass index (BMI), glycated hemoglobin, fasting blood glucose (FBG), and diabetes medications were assessed.

Ten patients were identified with GGF who had T2DM at the time of corrective surgery. Patients had a male-to-female ratio of 2:3, a mean age of 59.2 ± 10 years, a mean baseline BMI of 38.1 ± 17.6 kg/m², and a median duration of 9 years (interquartile range 6-14) from initial RYGB to revision. At a mean follow-up of 14.9 ± 8.5 months, a mean reduction in BMI of 4.9 ± 6 kg/m² was associated with a significant mean reduction in FBG (167.1 ± 88.2 vs. 106.1 ± 20.4 mg/dL, p = 0.04) and number of diabetes medications (1.4 ± 0.8 vs. 0.7 ± 0.7, p = 0.04).

In patients with diabetes and GGF, a corrective surgery for closure of fistula and restoration of bypass anatomy results in improvement of glucose control and status of diabetes medications. This finding can highlight the potential metabolic significance of duodenal exclusion.