Association Between the GGT/HDL-C Ratio and Ultrasonography-Defined NAFLD in Vietnamese Adults: A Cross-Sectional...

Background and aims. Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease associated with cirrhosis, hepatocellular carcinoma, and increased risks of liver-related and cardiovascular mortality. Many patients, however, remain asymptomatic until advanced stages. The gamma-glutamyl transferase to high-density lipoprotein cholesterol (GGT/HDL-C) ratio is a simple, noninvasive marker reflecting hepatic dysfunction and cardiometabolic imbalance. This study assessed its association with NAFLD and determined an optimal cutoff for identifying NAFLD. Methods. We conducted a cross-sectional analysis of 575 adults undergoing routine health examinations at the University of Medicine and Pharmacy Hospital in Ho Chi Minh City between 2021 and 2023. Participants with significant alcohol intake, viral hepatitis, or other chronic liver diseases were excluded. NAFLD was diagnosed by standardized abdominal ultrasonography based on increased hepatic echogenicity relative to the renal cortex or spleen. Associations between GGT/HDL-C and NAFLD were assessed by logistic regression (both as a continuous variable and by quartiles), and diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis. Statistical significance was defined as a two-tailed p-value < 0.05. Results. Individuals with NAFLD showed significantly higher BMI, prevalence of hypertension and diabetes, and elevated glucose, HbA1c, AST, ALT, GGT, cholesterol, triglycerides, and LDL-C, along with lower HDL-C. Each unit increase in the GGT/HDL-C ratio was associated with a 2% increase in the odds of NAFLD based on univariate logistic regression analysis. However, after adjustment for demographic and metabolic covariates, the GGT/HDL-C ratio was no longer independently associated with NAFLD. The highest quartile had an odds ratio of 7.05 (95% CI: 4.2-11.83) compared to the lowest. The area under the ROC curve for GGT/HDL-C was 0.72, outperforming GGT or HDL-C alone. A cutoff of 32.47 UI/mmol had 72.4% sensitivity and 63.3% specificity. Conclusions. The GGT/HDL-C ratio showed a significant unadjusted association with NAFLD and moderate discriminatory performance. However, because the association was no longer significant after full adjustment, the ratio should currently be considered a simple laboratory-based screening marker that requires further validation before routine clinical application.