There were 323 individuals (191 without AMI and 132 with AMI) in T2DM co-existent NAFLD patients who had serum samples, and serum FSTL3 was tested and mediation effect of FSTL3 in association of NAFLD fibrosis and AMI was performed. The gene discussed is FSTL3; the disease is metabolic dysfunction-associated steatotic liver disease.