Qualitative over quantitative lipids: electronegative subfractions h5 and l5 reveal hidden cardiovascular risk independent of standard lipid panels
A M H Tsai, R Y Chen, Y Chen, W L Hsu, C ChenAbstract
Background
Atherosclerotic cardiovascular disease (ASCVD) risk often persists despite achieving target levels in standard lipid panels. Qualitative modifications of lipoproteins, specifically the highly atherogenic and pro-inflammatory electronegative subfractions of HDL (H5) and LDL (L5), may drive this residual risk. This study investigates the correlation between these subfractions and quantitative lipid profiles, including total cholesterol (TC), LDL-C, HDL-C, triglycerides (TG), and lipoprotein(a) [Lp(a)].
Purpose
To determine whether electronegative subfractions H5% and L5% provide risk information distinct from standard lipid panels and Lp(a) in large clinical cohorts.
Methods
A large-scale cross-sectional analysis was performed (n=979 for H5; n=1345 for L5). H5% and L5% were isolated and quantified using ion-exchange chromatography. Pearson correlation (r) evaluated the relationships between subfraction proportions and serum lipid levels. Abnormal clinical thresholds were defined for standard lipids (TC > 200, LDL > 130, HDL < 50, TG > 250, Lp(a) > 30 mg/dL) and electronegative subfractions (H5 > 4%, L5 > 2%).
Results
H5 Subfraction (n=979): H5% demonstrated a strong positive correlation with Lp(a) (r=0.4778, p<0.001), with 8.17% of subjects showing dual elevation. In contrast, H5% showed no significant correlation with standard lipid markers: TC (r=0.0290), HDL-C (r=-0.0306), or TG (r=-0.0266). Notably, 5.82% of patients had pathologically high H5% despite having protective HDL-C levels (> 50 mg/dL). L5 Subfraction (n=1345): L5% showed a highly significant negative correlation with both total LDL-C (r=-0.3643, p<0.001) and TC (r=-0.3513, p<0.001), and a mild positive correlation with TG (r=0.1449, p<0.001). Importantly, a critical subset of patients harbored high atherogenic L5% despite maintaining optimal target levels of LDL-C < 130 mg/dL (5.35%) and TC < 200 mg/dL (4.31%).
Conclusions
Standard quantitative lipid panels fail to capture the entire spectrum of ASCVD risk. The distinct correlation of H5 with Lp(a) points to a synergistic, non-traditional atherogenic pathway. Furthermore, the inverse relationship between L5 and LDL-C/TC highlights that low cholesterol quantity does not guarantee benign cholesterol quality. Incorporating H5 and L5 testing into clinical practice could critically identify patients with hidden residual risk.Lipid Panel vs L5Lipid Panel vs H5