The Role of Non-HDL Cholesterol and Apolipoprotein B in Cardiovascular Disease: A Comprehensive Review

Atherosclerotic cardiovascular disease (ASCVD) remains the leading global cause of morbidity and mortality, even in the era of aggressive low-density lipoprotein cholesterol (LDL-C) lowering. This persistent residual risk has prompted a reevaluation of atherogenic lipid markers, with non-high-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein B (Apo B) emerging as superior indicators of the total atherogenic particle burden. Unlike LDL-C, non-HDL-C includes cholesterol from all atherogenic lipoproteins, while Apo B reflects the total number of atherogenic particles regardless of cholesterol content. Their clinical relevance is underscored in populations with diabetes, obesity, and hypertriglyceridemia, where LDL-C may not adequately reflect cardiovascular risk. This review explores the biological, clinical, and genetic foundations of non-HDL-C and Apo B as critical tools for risk stratification and therapeutic targeting. It highlights discordance analysis, inflammatory mechanisms in atherogenesis, the influence of metabolic syndromes, and their utility in specific populations, including those with chronic kidney disease and children with familial hypercholesterolemia. Additionally, the role of lipoprotein (a), glycation in diabetes, and hypertriglyceridemia are examined as contributors to residual risk. Clinical trials and genetic studies support Apo B and non-HDL-C as more robust predictors of cardiovascular events than LDL-C. Current guidelines increasingly endorse these markers as secondary or even preferred targets in complex lipid disorders. The incorporation of Apo B and non-HDL-C into routine clinical practice, especially for patients with residual risk, represents a paradigm shift toward personalized cardiovascular prevention. The review concludes with recommendations for guideline integration, emerging therapies, and future directions in biomarker-driven cardiovascular risk management.