Early Hepatic Alterations in Type 2 Diabetes: Diagnostic Value of Liver Viscosity in a Prospective Study

Background Type 2 diabetes mellitus (T2DM) is associated with a spectrum of liver disorders, ranging from nonalcoholic fatty liver disease to fibrosis and hepatocellular carcinoma. Early detection of hepatic changes is critical for risk stratification and management. Sound Touch Viscosity Imaging (STVi) allows noninvasive quantification of both tissue elasticity and viscosity, potentially providing complementary information beyond conventional stiffness measurements. This study aimed to evaluate the diagnostic value of liver viscosity as a biomarker in patients with T2DM. Methods 99 patients with T2DM and 73 healthy controls underwent liver assessment using STVi. Measurements of hepatic elasticity and viscosity were obtained under standardized protocols. Laboratory and demographic data were collected. Statistical analyses included Mann–Whitney U tests, Student’s t-tests, receiver operating characteristic (ROC) curve analysis, and multivariate logistic regression to assess the diagnostic performance of elasticity, viscosity, and their combination. Correlation between viscosity and elasticity was evaluated using Spearman analysis. Results T2DM patients showed significantly elevated liver viscosity (1.54 ± 0.36 Pa·s) and elasticity (7.37 ± 2.07 kPa) compared to controls (P < 0.001). Viscosity and elasticity were positively correlated (r = 0.683, P < 0.001). ROC analysis revealed superior diagnostic performance for viscosity (AUC = 0.836) over elasticity (AUC = 0.774), with the combined model yielding an AUC of 0.89. Multivariate analysis identified viscosity, ALT, and age as independent predictors of T2DM. Conclusions Liver viscosity serves as a sensitive biomarker for early liver alterations in T2DM, outperforming stiffness alone. Ultrasound-based viscosity imaging holds promise for non-invasive screening and risk stratification of liver injury in diabetic populations.