The Association of Lipoprotein(a) with Major Adverse Cardiovascular Events after Acute Myocardial Infarction: A Meta-Analysis of Cohort Studies

Background: Despite evidence suggesting a link between lipoprotein(a) (Lp(a)) and the occurrence of acute myocardial infarction (AMI), the relationship regarding prognoses related to AMI remains unclear. This meta-analysis was conducted to summarize the association between Lp(a) and the risks of major adverse cardiovascular events (MACEs) among populations surviving AMI. Methods: We searched PubMed, Embase, Web of Science, MEDLINE, and Cochrane Library databases until February 14, 2024. Cohort studies reporting multivariate-adjusted hazard ratios (HRs) for the correlation of Lp(a) with MACEs in AMI populations were identified. The Lp(a) level was analyzed using categorical and continuous variables. Subgroup analyses were conducted based on gender, type of AMI, diabetic and hypertensive status. Publication bias was assessed using funnel plots. A random-effect model was utilized to pool the results. Results: In total, 23 cohorts comprising 30,027 individuals were recruited. In comparison to those categorized with the lowest serum Lp(a), individuals in the highest category showed higher risks of MACEs after AMI (HR: 1.05, 95% confidence interval (CI): 1.01–1.09, p = 0.006). Similar findings were exhibited when Lp(a) was analyzed as a continuous variable (HR: 1.14, 95% CI: 1.02–1.26, p = 0.02). Subgroup analyses indicated that this correlation persisted significantly among females (HR: 1.23, p = 0.005), diabetes mellitus (DM) (HR: 1.39, p = 0.01), hypertension (HR: 1.36, p < 0.00001), ST-segment elevation myocardial infarction (STEMI) (HR: 1.03, p = 0.04), non-STEMI (HR: 1.40, p = 0.03), and long-term (>1 year) MACE (HR: 1.41, p = 0.0006) subgroups. Conclusions: Higher Lp(a) levels might be an independent indicator for MACE risks after AMI, especially among female populations with DM and/or hypertension, and more suitable for evaluating long-term MACEs. The PROSPERO Registration: CRD42024511985, https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024511985.