# Association Between Lipid-Lowering Therapy and Differences in the Distribution of LDL-C, apoB and non-HDL-C

## TL;DR

This study shows that lipid-lowering therapy, especially combined therapy, reduces discrepancies between different cholesterol markers in patients.

## Contribution

The study demonstrates that combined lipid-lowering therapy is more effective in reducing discordance between LDL-C and apoB levels than monotherapy.

## Key findings

- Discordance between LDL-C and apoB was observed in 26.6% of untreated patients and reduced to 13.6% with any therapy.
- Combined therapy reduced discordance between LDL-C and non-HDL-C to 4.8%, compared to 8.4% with monotherapy.
- Combined lipid-lowering therapy was more effective in aligning cholesterol markers than statin monotherapy.

## Abstract

Background: The diagnosis of hypercholesterolemia relies on the laboratory assessment of lipid parameters. This study aimed to evaluate differences in the distribution of low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), and apolipoprotein B (apoB) concentrations according to the presence and type of lipid-lowering therapy (LLT). Methods: This retrospective analysis included consecutive patients who had at least one measurement of LDL-C, apoB, and non-HDL-C between March and November 2024 in a high-volume tertiary hospital. All lipid fractions were expressed as the percentages of measurements above or below cut-off values established by the recent ESC guidelines. Subgroup analysis based on LLT type was performed, with patients categorized as receiving either single or combined LLT. Results: A total of 5048 patients were included in the analysis. Among patients receiving LLT, most were on statin monotherapy (77.3%), predominantly atorvastatin. Combined therapy, primarily statin plus ezetimibe, was used in 22.7% of treated patients. Discordance between on-target apoB levels and elevated LDL-C concentrations occurred in 26.6% of untreated and 13.6% of all treated patients, and in 15.1% and 8.6% of single and combined-LLT patients, respectively. Similarly, discordance between on-target non-HDL-C and elevated LDL-C levels was observed in 13.5% of untreated and 7.5% of all treated patients, and in 8.4% and 4.8% of single and combined-LLT patients, respectively. Conclusions: Classification of hyperlipidemia based on LDL-C, non-HDL-C, and apoB concentrations reveals significant discrepancies between these markers, especially between LDL-C and apoB. LLT reduces these discrepancies with combined LLT being particularly effective.