Lipoprotein(a) is associated with premature coronary artery disease: a meta-analysis

Background Lipoprotein(a) is associated with adverse cardiovascular outcomes and its association with premature coronary artery disease (pCAD) is underexamined. The primary aim of the study is to compare serum lipoprotein(a) levels between pCAD cases and controls. Methods We conducted a systematic review and the MEDLINE database, ClinicalTrials.gov, medRxiv and Cochrane Library were searched for studies evaluating lipoprotein(a) and pCAD. Standardized mean differences (SMD) of lipoprotein(a) in pCAD patients versus the controls were pooled by a random-effects meta-analysis. The presence of statistical heterogeneity was evaluated with the Cochran Q chi-square test and the quality of the included studies was assessed via the Newcastle-Ottawa Scale. Results A total of 11 studies were found eligible, reporting on the difference in lipoprotein(a) levels between pCAD patients and controls. Serum lipoprotein(a) concentration was found significantly increased in patients with pCAD (SMD = 0.97; 95% confidence intervals, 0.52–1.42; P < 0.0001; I 2 = 98%) as compared to controls. High statistical heterogeneity and relatively small case-control studies of moderate quality are the main limitations of this meta-analysis. Conclusion Lipoprotein(a) levels are significantly increased in patients with pCAD as compared to controls. Further studies are needed to clarify the clinical significance of this finding.