Low-density lipoprotein cholesterol to apolipoprotein B ratio as a predictor of clinical outcomes following percutaneous coronary intervention: a propensity score-matched analysis.

Residual cardiovascular risk after percutaneous coronary intervention (PCI) remains a concern despite optimal low-density lipoprotein cholesterol (LDL-C) management. The LDL-C/apolipoprotein B (ApoB) ratio is a potential marker for LDL particle size and atherogenicity. This study investigated the prognostic value of the pre-treatment LDL-C/ApoB ratio for major adverse cardiac events (MACE) in patients with coronary artery disease who underwent PCI. Among 2116 consecutive patients enrolled between 2015 and 2022 in the Fukuoka University PCI prospective registry, this study analyzed 1682 individuals who were divided into two groups according to their LDL-C/ApoB ratio (< 1.2 vs. ≥ 1.2). The primary outcome was 3-year MACE. After propensity score matching (315 pairs), the low LDL-C/ApoB ratio (< 1.2) was associated with higher MACE (Adjusted HR 1.50, 95% CI 1.04-2.16, p = 0.030). Restricted cubic spline analysis in the matched cohort revealed a significant continuous inverse association between the LDL-C/ApoB ratio and MACE risk. Notably, this predictive value persisted even after propensity score matching balanced for triglyceride-rich lipoprotein-related markers (triglycerides, remnant-like particle cholesterol) and HDL-C. The pre-treatment LDL-C/ApoB ratio is an independent predictor of MACE after PCI, demonstrating a continuous inverse relationship with risk, even when accounting for other atherogenic lipoproteins. This easily calculable ratio may enhance risk stratification by identifying residual risk associated with LDL particle characteristics.