RESUMO
AIM: Hepatic fibrosis is associated with various factors, including metabolic dysfunction-associated fatty liver disease (MAFLD), insulin resistance, and alcohol intake in patients with morbid obesity. We investigated factors directly associated with hepatic fibrosis in patients with morbid obesity using a graphical model. METHODS: We enrolled 134 consecutive patients with morbid obesity who underwent liver biopsy during sleeve gastrectomy (median age 43.5 years; MAFLD 78.4%; homeostasis model assessment of insulin resistance [HOMA-IR] 5.97; >20 g/day alcohol intake 14.2%). Patients were classified into none/mild (F0/1; n = 77) or significant/advanced fibrosis (F2/3; n = 57) groups, based on histology. Factors associated with F2/3 were analyzed using logistic regression analysis and a graphical model. RESULTS: F2/3 was observed in 42.5% of the enrolled patients. The prevalence of MAFLD and HOMA-IR values were significantly higher in the F2/3 group than in the F0/1 group; however, no significant difference in alcohol intake was observed between the two groups. On logistic regression analysis, MAFLD, but not HOMA-IR or alcohol intake, was the only independent factor associated with F2/3 (odds ratio 7.555; 95% confidence interval 2.235-25.544; p = 0.0011). The graphical model revealed that F2/3 directly interacted with MAFLD, diabetes mellitus, HOMA-IR, and low-density lipoprotein cholesterol. Among these factors, MAFLD showed the strongest interaction with F2/3. CONCLUSIONS: We determined that MAFLD was more directly associated with significant/advanced fibrosis than insulin resistance or hyperlipidemia, and alcohol intake was not directly associated with hepatic fibrosis. Metabolic dysfunction-associated fatty liver disease could be the most important factor for hepatic fibrosis in patients with morbid obesity.