Improved glycemic control with proximal intestinal bypass and weight loss following gastrectomy in non-obese diabetic gastric cancer patients

Purpose: The aim of this study was to assess whether gastrectomy influences glycemic control in non-obese diabetic gastric cancer patients and to identify factors related to glucose metabolism after gastrectomy. Materials and Methods: We retrospectively analyzed changes in glucose metabolism in 238 non-obese (body mass index < 30 kg/m2) patients with type II diabetes who underwent distal gastrectomy with either gastroduodenostomy (n = 91) or gastrojejunostomy (n = 147) for stage I gastric cancer. We collected demographics, diabetes-related features, surgery-related features, and changes in glucose metabolism during follow-up. The effect of surgery on the course of diabetes was evaluated at different time points according to fasting blood glucose levels and use of diabetes-related medication. Results: Preoperatively, the mean body mass index was 24.3 ± 2.3. Weight, body mass index and fasting blood glucose of all patients were significantly lower compared to preoperative levels at all time points. Weight loss after 6 months and the percentage of patients whose weight loss ratio was higher than 10% after one year were greater in the gastrojejunostomy group than the gastroduodenostomy group. Overall, 88 (37%) patients showed improvement in their diabetes course at one month after surgery; 152 (64%) showed improvement after 2 years. Duration of diabetes, weight loss, and reconstruction type were associated with improvement in diabetes at different time points. At 6 months and thereafter, the percentage of patients with an improved diabetes course was highest in the gastrojejunostomy plus higher than 10% weight loss group. Conclusions: Although weight loss may be associated with adverse effects of gastrectomy, postoperative weight loss in an acceptable range is a useful measure of the better glycemic control for the group of diabetic patients. Selecting gastrojejunostomy during gastrectomy and inducing acceptable weight loss after gastrectomy could be beneficial to the non-obese diabetic gastric cancer patients for improved glycemic control.