Abstract
Purpose: Insulin resistance is prevalent in patients with obesity and type 2 diabetes (T2DM). The study aimed to assess the effects of laparoscopic sleeve gastrectomy (LSG) on body weight and glycemic status in patients with morbid obesity with and without T2DM. Methods: This prospective study involved 100 patients suffering from morbid obesity divided into two equal groups; 50 patients with T2DM and 50 nondiabetic patients, who were scheduled for LSG. The glycemic status was assessed before and after surgery by blood glucose levels, HbA1c, fasting insulin, c-peptide, and homeostasis model assessment of insulin resistance (HOMA-IR). Results: In the two groups, plasma glucose levels and HbA1c decreased significantly 1, 3, and 6 months after surgery relative to the preoperative readings. In the two groups, fasting insulin, C-peptide, and HOMA-IR decreased significantly 1, 3, and 6 months after surgery. There was no correlation between percentage of excess weight loss (%EWL) and C-peptide, HbA1c, fasting, and postprandial plasma glucose, fasting insulin, and HOMA-IR. C-peptide was correlated positively with HbA1c, fasting and postprandial plasma glucose, fasting insulin, and HOMA-IR. Conclusion: LSG produced a significant reduction in weight and body mass index in diabetic and nondiabetic patients 6 months after surgery with significant reduction of insulin resistance as early as 1 month after surgery independent of weight loss.