Pre-percutaneous coronary intervention lipoprotein (a) levels and its association with angiographically confirmed restenosis – a study level meta-analysis
H Rai, O A Hofmann, J Haneberg, D O'Callaghan, J J Coughlan, R Colleran, R A ByrneAbstract
Background
Elevated levels of lipoprotein(a) [Lp(a)] is considered to be an established and independent risk factor for coronary artery disease (CAD) and has been shown to be associated with worse outcomes amongst patients with already established CAD. Association status of baseline Lp(a) levels with prognosis of percutaneous coronary intervention (PCI), especially with respect to incidence of restenosis, however, still remains contentious.
Purpose
We conducted a systematic review and study-level meta-analysis to evaluate the relationship between pre-PCI Lp(a) levels and the incidence of coronary restenosis.
Methods
Online databases of PubMed, EMBASE, MEDLINE, Scopus, and Web of Knowledge were systematically searched for relevant articles published until November 11th, 2025. Qualifying studies had to have: (i) an angiographically determined restenosis group, (ii) an angiographically or clinically determined no-restenosis group, and/or (iii) published summary pre-PCI Lp(a) levels for both groups. Data was extracted from included studies, was transformed (if needed) and further synthesized for summary effect measures of standardized mean difference (SMD), mean difference (MD), and incidence rate ratio (IRR). Study level results were pooled using Z-test employing appropriate effects for analysis. Begg’s funnel plots and Egger’s test were used to detect publication bias.
Results
From 307 unique records retrieved, 24 studies were included for SMD based analysis (n= 4,596), 13 for MD based analysis (n= 2,016), whilst 17 for IRR based analysis (n= 9,633). Cases with coronary restenosis overall, were found to have significantly higher pre-PCI Lp(a) levels, demonstrating small-moderate effect size (SMD= 0.25), whilst the mean difference in Lp(a) levels between the restenosis and no-restenosis groups was found to be 5.87 mg/dl (SMD= 0.25, 95% CI= 0.11-0.38, p= 0.0003 and MD= 5.87, 95% CI= 1.78-9.96 mg/dl, p= 0.005 respectively). In addition, the risk of coronary restenosis was demonstrated to be 37% higher in patients with clinically elevated pre-PCI Lp(a) levels as compared to the rest (IRR= 1.37, 95% CI= 1.14-1.64, p= 0.0007). A graphical abstract showcasing aims, methods and main results of the present analysis is displayed as Figure 1. We found no evidence of publication bias amongst the analysed study groups and our leave-one-out sensitivity analyses further confirmed the robustness of our findings.
Conclusions
The present systematic review and meta-analysis confirms the association between elevated pre-PCI Lp(a) levels and angiographically confirmed coronary restenosis. Our findings underscore the potential of Lp(a) as a biomarker for risk stratification at the time of index PCI, helping to identify patients who may benefit from closer clinical monitoring and intensified secondary prevention strategies.