The triglycerides × glucose (TyG) index is a recently proposed surrogate marker of insulin resistance (IR), calculated from fasting plasma triglyceride and glucose concentrations. We tested the host and viral factors associated with Tyg and homeostasis model assessment (HOMA) scores, comparing their associations with histological features and with sustained virological response (SVR) in patients with genotype 1 chronic hepatitis C(G1CHC). Three hundred and forty consecutive patients with G1CHC were considered. All had a liver biopsy scored by one pathologist for staging and grading (Scheuer), and graded for steatosis, which was considered moderate-severe if ≥30%. Anthropometric and metabolic measurements, including IR measured by both HOMA and TyG, were registered.
By linear regression analysis, TyG was independently associated with waist circumference (WC), total cholesterol, presence of arterial hypertension, Log10 HCV-RNA and steatosis. Similarly, WC and steatosis were significantly associated with HOMA. Older age (OR, 1.036; 95%CI, 1.004-1.070, P = 0.02), higher WC (1.031; 1.004-1.060; P = 0.02) and higher TyG (11.496; 3.163-41.784; P < 0.001) were linked to moderate-to-severe steatosis (≥30%) by multiple logistic regression analysis. When TyG was replaced by HOMA-IR in the model, the latter remained significantly associated with steatosis ≥30% (1.237; 1.058-1.448; P = 0.008). Receiver operating characteristic curves showed a similar performance of TyG (AUC 0.682) and HOMA-IR (AUC 0.699) in predicting moderate-severe steatosis.
No independent associations were found between both TyG and HOMA and fibrosis or SVR. In patients with G1CHC , TyG, an easy-to-calculate and low-cost surrogate marker of IR, is linked to liver steatosis and shows an independent association with viral load.