Lipoprotein (a) and Kidney Function: A Correlation Study

Background: Recent evidence implicates Lipoprotein(a) [Lp(a)] as a potent atherogenic factor, surpassing LDL in its cardiovascular risk. Despite this, the dynamics of plasma Lp(a) levels across varying stages of renal function, as defined by estimated Glomerular Filtration Rate (eGFR), remain inadequately explored. This retrospective study aims to investigate the relationship between plasma Lp(a) concentrations and renal function, utilizing a large patient cohort. Methods: Between January 2019 and December 2022, data from 141,376 patients at Guangdong Provincial People’s Hospital, including renal function parameters and lipid profiles, were analyzed. Lipid markers studied encompassed Lp(a), triglycerides (TG), total cholesterol (TC), HDL-C, LDL-C, Apo A1, and Apo B. Patients were stratified into five groups per eGFR levels aligning with chronic kidney disease stages (KDIGO guidelines). Plasma Lp(a) levels were compared across these groups through the Kruskal-Wallis test, with statistical analyses performed using SPSS version 22.0. Results: The median plasma Lp(a) concentration in the study population was 166.0 mg/L (IQR: 91.0 - 346.0 mg/L). Importantly, the median plasma Lp(a) levels (IQR) showed a progressive increase across the five eGFR groups, as follows: eGFR ≥ 90 mL/min/1.73 m2 : 153.0 (85.0, 313.0) mg/L;eGFR 60-89 mL/min/1.73 m2: 172.0 (95.0, 351.0) mg/L;eGFR 30-59 mL/min/1.73 m2: 203.0 (107.0, 422.0) mg/L;eGFR 15-29 mL/min/1.73 m2: 235.0 (125.0, 469.0) mg/L;eGFR < 15 mL/min/1.73 m2 : 260.5 (148.0, 460.0) mg/L.Statistical analysis revealed a highly significant difference in Lp(a) levels among the groups (p< 0.01), with pairwise comparisons also demonstrating statistically significant differences between each group (p < 0.01). Notably, this trend was not observed for other lipid markers including LDL-C and ApoB. Conclusion: Our findings underscore a clear association between plasma Lp(a) concentrations and renal function decline. As eGFR decreases, there is a discernible rise in plasma Lp(a) levels, highlighting its potential role in renal dysfunction progression.