ApoB/ApoA-I Ratio Identifies Hidden Atherogenic Risk Beyond Conventional Lipid Parameters in Normolipidemic Adults

Dyslipidemia is a major modifiable risk factor for atherosclerotic cardiovascular diseases (ASCVD). However, conventional lipid parameters may underestimate cardiovascular risk in individuals with normolipidemic profiles. The apolipoprotein B (ApoB)/apolipoprotein A-I (ApoA-I) ratio has emerged as a sensitive marker reflecting the balance between proatherogenic and antiatherogenic lipoproteins. This cross-sectional analytical study included 104 apparently healthy adults aged 23-68 years with normal lipid profiles. Serum lipid and apolipoprotein levels were measured using standard enzymatic and immunoturbidimetric methods. Statistical analyses included correlation, group comparison, and multivariate regression analysis. Males demonstrated significantly higher triglycerides, lower high-density lipoprotein cholesterol (HDL-C) and elevated ApoB/ApoA-I ratios compared with females (p < 0.05). Participants with an ApoB/ApoA-I ratio > 0.8 showed significantly higher total cholesterol, low-density lipoprotein cholesterol (LDL-C), non-HDL-C, triglycerides, and atherogenic indices, along with lower HDL-C (p < 0.05), despite having lipid values within normal ranges. Strong positive correlations were observed between the ApoB/ApoA-I ratio and atherogenic lipid markers. Multivariate regression identified LDL-C and LDL/ApoB ratio as independent predictors of the ApoB/ApoA-I ratio. The ApoB/ApoA-I ratio can identify hidden atherogenic risk not detected by conventional lipid parameters, indicating possible misclassification of cardiovascular risk in normolipidemic individuals. Additional assessment using apolipoproteins could enhance risk stratification in the initial phases. However, further longitudinal studies are required to establish the predictive value for clinical cardiovascular outcomes.