Therapeutic effects of metabolic bariatric surgery on non-alcoholic fatty liver disease are influenced by low density lipoprotein

Abstract

Background: Metabolic bariatric surgery (MBS) improves Non-Alcoholic Fatty Liver Disease (NAFLD). However, there is limited data on MBS impact in NAFLD of obese patients in China. We aim to address the issue in this study. Methods: We conducted a retrospective analysis of 439 obese patients who underwent laparoscopic sleeve gastrectomy at the Department of Metabolic Surgery of Zhengzhou Central Hospital between January 2022 and March 2023. Patients were divided into two groups (Control/30 patients and NAFLD/409 patients) based on the liver functional parameters (AST, ALT, and GGT) and ultrasound results. At one-year post-surgery, MBS impact in NAFLD was examined by comparing the two groups in those parameters plus percentage of Excess Weight Loss (EWL). Other parameters included: body weight-related indicators (weight, waist circumference, body mass index (BMI), insulin sensitivity-related markers (fasting blood glucose, fasting insulin, and Homeostasis Model Assessment of Insulin Resistance), and blood lipid profiles (TC, TG, HDL, and LDL). Results: The patients of NAFLD group exhibited significantly higher levels in parameters (BMI, insulin resistance, ALT, AST, GGT, and TG) and lower level of HDL before the surgery. Results of 122 patients were collected at one year after surgery and those parameters were significantly improved in the NAFLD group compared to the preoperative levels (P < 0.01). Patients with high LDL exhibited a reduced response in NAFLD resolution (OR=0.18, p=0.01). A higher percentage of EWL was associated with an increased therapeutic response in NAFLD resolution (p<0.05). Other metabolic parameters showed no significant relationship with the NAFLD resolution. Conclusion: MBS has shown significant effects on obesity and NAFLD. NAFLD resolution after surgery was positively associated with percentage of EWL in the obese patients. Individuals with higher LDL levels before MBS have a lower postoperative NAFLD resolution rate. LDL may serve as a predictive indicator of NAFLD resolution after surgery.