Association Among Liver Enzymes, Liver-to-Spleen Hounsfield Unit Ratio, and Glycemic Profiles After Sleeve Gastrectomy in Diabetic and Non-Diabetic Japanese Patients with Obesity: A Retrospective Pilot Study

Background and Objectives: This study investigated the correlation of the liver-to-spleen (L/S) Hounsfield unit ratio on abdominal CT with liver function and diabetic indicators before and after laparoscopic sleeve gastrectomy (LSG), comparing patients with and without diabetes mellitus (DM and non-DM groups). Methods: Patients undergoing LSG were categorized into DM and non-DM groups. Metabolic parameters and abdominal CT scans were assessed preoperatively and one year postoperatively. Correlations among these variables were analyzed, and intergroup comparisons were performed. Results: Preoperative body weight and postoperative weight loss were comparable between the DM and non-DM groups. Before surgery, the DM group showed significantly higher levels of fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), aspartate transaminase (AST), alanine transaminase (ALT), and γ-glutamyl transpeptidase (γ-GTP). After LSG, both groups exhibited significant reductions in FPG, HbA1c, AST, ALT, and γ-GTP, along with a significant increase in the L/S ratio. The reduction in γ-GTP was more pronounced in the DM group. In the DM group, changes in glycemic markers (FPG and HbA1c) were significantly correlated with changes in liver enzymes and with the change in L/S ratio. Conclusions: LSG reduced body weight and fat mass and improved glucose metabolism and liver function in patients with obesity, regardless of their diabetes status. Improvements in liver enzymes and/or the L/S ratio were more marked in diabetic patients and might be closely linked to better glycemic control following surgery.