Plasma glycosylated hemoglobin to high-density lipoprotein cholesterol ratio (HbA1c/HDL-C), Non-alcoholic fatty liver disease (NAFLD), Practical indicator, National health and nutrition examination survey (NHANES), Diseases of the digestive system. Gastroenterology, RC799-869

Abstract Background Non-alcoholic fatty liver disease (NAFLD), a metabolic liver disorder closely associated with obesity and diabetes, urgently requires early screening. This population-based study is the first to explore the relationship between glycemic control and a novel dyslipidemia composite index—the glycated hemoglobin/high-density lipoprotein cholesterol (HbA1c/HDL-C) ratio in individuals with NAFLD and liver fibrosis. Methods Data from 5,891 adults in the 2017–2020 National Health and Nutrition Examination Survey (NHANES) were analyzed. Binary logistic regression and restricted cubic spline (RCS) analyses were used to evaluate the association between HbA1c/HDL-C ratio and the risk of NAFLD and liver fibrosis. The reliability of the results was confirmed using subgroup, interaction, and sensitivity analyses. Screening performance was assessed using receiver operating characteristic (ROC) curves, and differences between various indicators were compared using the DeLong test. Results After adjusting for confounding factors, each 1% increase in the HbA1c/HDL-C ratio was associated with a 20% higher risk of NAFLD (odds ratio [OR] = 1.20, 95% confidence interval [CI]: 1.14–1.27, P