Models incorporating physical, laboratory and gut metabolite markers can be used to predict severe hepatic steatosis in <scp>MAFLD</scp> patients

Metabolic-associated fatty liver disease (MAFLD) induced-severe hepatic steatosis poses significant health risks. Early prediction of this condition is crucial for prompt intervention. Short-chain fatty acids (SCFAs) and tryptophan are gut metabolites correlated with MAFLD pathogenesis in the gut-liver axis. This study aims to construct prediction models for severe hepatic steatosis by including SCFAs and tryptophan metabolites. This study enrolled 83 participants from the outpatient department in 2023. Physical measurements, serum metabolic and inflammatory markers, metabolites of serum SCFAs and tryptophan were collected. Severe hepatic steatosis was diagnosed using vibration-controlled transient elastography and abdominal sonography. All 40 (48.2%) participants diagnosed with severe hepatic steatosis had MAFLD, while approximately three-quarters of those without severe hepatic steatosis had MAFLD. In comparison to the non-severe hepatic steatosis group, individuals with severe hepatic steatosis exhibited higher levels of waist and arm circumference, serum triglyceride (TG), and lower levels of serum high-density lipoprotein cholesterol (HDL-C) and AST/ALT ratio. They also had higher serum levels of lipopolysaccharide-binding protein, isovaleric acid, and propionic acid, and lower levels of 3-methylvaleric acid, indole-3-propionic acid, and indoxyl sulfate. Models incorporating these markers predicted severe hepatic steatosis. One model additionally included waist circumference and triglyceride-glucose index, while the other incorporated arm circumference and TG/HDL-C ratio. The area under the curve reached 0.958 and 0.938, respectively (p < 0.001). SCFAs and tryptophan metabolites are valuable in predicting severe hepatic steatosis. Further research is needed to investigate the roles of these metabolites in MAFLD.