The Association of Lipoprotein(a) and Stroke Recurrence: A Systematic Review and Meta-Analysis

Background and Purpose Lipoprotein(a) [Lp(a)] is a lipoprotein structurally similar to low-density lipoprotein and is considered a genetically determined risk factor for cardiovascular disease. Although Lp(a) has been linked to ischemic stroke, its role in secondary stroke prevention, particularly in stroke recurrence, remains unclear. Methods A systematic search of MEDLINE and Scopus databases was conducted to identify randomized controlled trials (RCTs) and observational studies reporting Lp(a) levels in patients with ischemic stroke or transient ischemic attack. The primary outcome was stroke recurrence, and secondary outcomes included poor functional outcome, all-cause mortality, and recurrent vascular events. Pooled odds ratios (ORs) were calculated using a random-effects model. Results A total of 12 studies, including one RCT post hoc analysis and 11 observational studies, comprising 17,903 patients (mean age 63 years, 38% female), were included. Elevated Lp(a) levels were significantly associated with increased stroke recurrence (OR: 1.69; 95% confidence interval [CI]: 1.09–2.63; P=0.020) and poor functional outcome (OR: 2.09; 95% CI: 1.40–3.11; P<0.001). No significant associations were found between Lp(a) levels and all-cause mortality (OR: 2.20; 95% CI: 0.89–5.43; P=0.088) or recurrent vascular events (OR: 2.66; 95% CI: 0.95–7.44; P=0.063). Conclusion Elevated Lp(a) levels are linked to increased stroke recurrence and poor functional outcome in stroke patients. Lp(a) may represent a novel therapeutic target in secondary stroke prevention in addition to a promising biomarker.