Clinical significance of lipoprotein(a) in patients hospitalized with acute coronary syndromes: a contemporary real-world cohort study

Background Lipoprotein(a) [Lp(a)] is an established genetically determined cardiovascular risk factor; however, comprehensive real-world data on its distribution and clinical significance in patients hospitalized with acute coronary syndromes (ACS) remain limited. We aimed to characterize Lp(a) concentrations in a contemporary Polish ACS population and evaluate their associations with clinical characteristics, angiographic extent of coronary artery disease, cardiovascular comorbidities, renal function, and lipid-lowering therapy. Methods This retrospective single-center study included 1009 consecutive patients hospitalized with ACS between November 2022 and February 2025. Serum Lp(a) concentrations were measured within 24 h of admission using an immunoturbidimetric assay. Clinical, laboratory, echocardiographic, and angiographic data were analyzed. Elevated Lp(a) was defined as ≥ 75 nmol/L according to current Polish expert recommendations. Multivariable logistic regression was performed to assess the associations between admission Lp(a) concentrations and multivessel coronary artery disease and polyvascular disease. An expanded sensitivity model additionally adjusted for LDL-C, admission eGFR, pre-admission statin intensity, ACS phenotype, and heart failure. Results A total of 1009 patients (mean age 69.6 ± 10.9 years; 62.6% men) were included. The median admission Lp(a) concentration was 23.8 nmol/L, and 28.9% of patients met the study-defined threshold for elevated admission Lp(a) (≥ 75 nmol/L). In Model 1, each doubling of admission Lp(a) was associated with higher odds of multivessel coronary artery disease (OR 1.09, 95% CI 1.01–1.16; P = 0.018) and polyvascular disease (OR 1.11, 95% CI 1.01–1.23; P = 0.040). In the expanded Model 2, these associations were attenuated and no longer statistically significant (OR 1.06, 95% CI 0.99–1.14; P = 0.096 and OR 1.10, 95% CI 0.99–1.22; P = 0.079, respectively). Patients with peripheral artery disease had numerically higher admission Lp(a) concentrations, but the difference did not remain significant after false discovery rate adjustment (adjusted P = 0.119). Admission Lp(a) concentrations increased numerically across categories of lower admission eGFR, but the overall difference was not statistically significant ( P = 0.051). Admission Lp(a) concentrations showed a weak positive correlation with NT-proBNP (Spearman’s ρ = 0.087; domain-specific FDR-adjusted P = 0.011), although this association was not statistically significant after pooled FDR adjustment across all exploratory analyses (adjusted P = 0.073). Among patients with coronary artery disease, 22.7% had no documented pre-admission lipid-lowering therapy. Conclusions Elevated admission Lp(a) concentrations were common in this contemporary cohort of Polish patients hospitalized with ACS. Higher admission Lp(a) concentrations were associated with greater atherosclerotic burden in the initial multivariable model, but these associations were attenuated and no longer statistically significant after expanded adjustment. Exploratory analyses showed a weak positive correlation with NT-proBNP, whereas the observed differences according to PAD status and admission renal function were not statistically significant after the corresponding multiplicity adjustment or overall testing. These findings provide a contemporary characterization of admission Lp(a) in patients with ACS and support further prospective studies incorporating repeated Lp(a) measurements and longitudinal cardiovascular outcomes. Clinical trial number Not applicable.