Association of Coronary Atherosclerosis with Hyperapobetalipoproteinemia: Normal Cholesterol but Elevated ApoB

This landmark 1980 cross-sectional study — the original paper introducing the concept of hyperapobetalipoproteinemia — examined 90 subjects (40 with angiographically documented coronary artery disease, 50 controls) and measured both LDL cholesterol and ApoB concentrations.

A subset of CAD patients had normal LDL-C but elevated ApoB — identifying a new metabolic phenotype the investigators called “hyperapobetalipoproteinemia.” These patients had high LDL particle number with normal LDL cholesterol content per particle: the hallmark of the discordance between LDL-C and ApoB that is now central to cardiovascular risk stratification. The condition was more common in CAD patients than controls.

The clinical significance of this 1980 paper is profound given subsequent evidence. Sniderman and colleagues identified — 40+ years before it entered mainstream cardiology — that some patients with “normal” LDL-C carry substantially elevated atherosclerotic burden, detectable only by measuring ApoB. The paper established the conceptual foundation for all subsequent ApoB discordance research.

By modern standards, 90 subjects with cross-sectional design produces limited-evidence strength. But the clinical significance is maximal: this was the founding empirical demonstration that cholesterol content and particle number diverge, and that patients with elevated particles at normal cholesterol levels carry excess coronary disease.

We rate the evidence limited by modern standards. A historically decisive founding study establishing the hyperapobetalipoproteinemia concept — elevated ApoB with normal LDL-C and excess coronary disease — that launched 40 years of subsequent ApoB validation research.