Association Between Ratio of Cholesterols and Coronary Artery Stenosis According to Low-Density Lipoprotein-Cholesterol Levels and Statin Use

BACKGROUND AND OBJECTIVES: Low-density lipoprotein cholesterol (LDL-C) remains the principal therapeutic target in preventing atherosclerotic cardiovascular disease. Nevertheless, coronary artery disease (CAD) may develop even in patients whose LDL-C levels are at recommended targets. Using a contemporary Korean multicenter registry, we examined the association between lipid parameters and CAD in patients with suspected angina, considering statin use and LDL-C levels. METHODS: We analyzed data from 2,410 adults with chest pain who underwent coronary angiography at 21 centers in South Korea (2012-2022). CAD was defined as ≥50% stenosis in major coronary arteries. To address multicollinearity among lipid parameters, principal component analysis-derived components were evaluated in multivariable logistic regression, with additional assessment of model discrimination using net reclassification improvement (NRI) and integrated discrimination improvement (IDI). RESULTS: Among the study population (60.1% women), 52.0% were on statins, and 36.5% were diagnosed with CAD, which was more frequent in statin users. The proportion of patients with LDL-C within target ranges was similar between statin users and non-users (p=0.695). Total cholesterol/high-density lipoprotein cholesterol (HDL-C) ratio, non-HDL-C/HDL-C ratio, and LDL-C/HDL-C ratio showed significant associations with CAD. These associations remained consistent regardless of statin use or LDL-C levels. Total cholesterol/HDL-C and non-HDL-C/HDL-C ratios moderately improved model performance (NRI: 0.413, IDI: 0.024); LDL-C/HDL-C ratio showed mild improvement (NRI: 0.373, IDI: 0.030). CONCLUSIONS: In this large, real-world Korean cohort, cholesterol ratios showed cross-sectional associations with CAD. These associations remained consistent regardless of statin use or LDL-C levels.