Discordance of Small Dense LDL Cholesterol Beyond LDL Cholesterol or Non–HDL Cholesterol and Carotid Plaque

Background

Different low-density lipoprotein (LDL) particles exhibit distinct proatherogenic properties.

Objectives

This study sought to evaluate associations of small dense low-density lipoprotein cholesterol (sdLDL-C), large buoyant low-density lipoprotein cholesterol (lbLDL-C), sdLDL-C/LDL-C ratio, and sdLDL-C/lbLDL-C ratio with carotid plaque (CP) risk in the general population, and to perform discordance analyses to determine which biomarker better reflects CP risk beyond low-density lipoprotein cholesterol (LDL-C) and non–high-density lipoprotein cholesterol (non-HDL-C).

Methods

This study enrolled 20,369 participants from Beijing Health Management Cohort. Discordant sdLDL-C, lbLDL-C, or ratio metrics (sdLDL-C/LDL-C and sdLDL-C/lbLDL-C) relative to LDL-C or non-HDL-C, and discordant ratio metrics relative to sdLDL-C, were defined by residual differences and median values. Logistic regression models were used to estimate ORs and 95% CIs.

Results

In this study, higher levels of sdLDL-C (OR: 1.354; 95% CI: 1.299-1.410), sdLDL-C/LDL-C ratio (OR: 1.196; 95% CI: 1.148-1.247), and sdLDL-C/lbLDL-C ratio (OR: 1.153; 95% CI: 1.110-1.197) were more strongly associated with increased odds of CP than lbLDL-C (OR: 1.110; 95% CI: 1.070-1.151). Additionally, discordantly high sdLDL-C or low lbLDL-C relative to LDL-C or non-HDL-C were associated with increased odds of CP, whereas discordantly low sdLDL-C or high lbLDL-C were associated with reduced odds. Finally, discordantly high sdLDL-C/LDL-C and sdLDL-C/lbLDL-C ratios relative to LDL-C, non-HDL-C, or sdLDL-C were linked to increased odds of CP.

Conclusions

The sdLDL-C, sdLDL-C/LDL-C, and sdLDL-C/lbLDL-C, but not lbLDL-C, are superior to LDL-C and non-HDL-C in identifying individuals at increased risk of CP. The sdLDL-C/LDL-C and sdLDL-C/lbLDL-C ratios may capture additional risk information beyond sdLDL-C.