Abstract TP138: Elevated lipoprotein (a) is associated with occurrence of cardiovascular events in stroke survivors

Introduction: Lipoprotein(a) [Lp(a)] has been associated with increased risk of cardiovascular disease. However, its relationship with ischemic stroke risk remains inconsistent across studies. Cardiovascular guidelines recommend measuring Lp(a) at least once in a lifetime for all adults. This study assessed the relationship between Lp(a) levels and the risk of stroke and future cardiovascular events in stroke survivors. Methods: This retrospective cohort study included patients with ischemic stroke who had Lp(a) testing between 2017-2024 at a single academic center. Outcomes included stroke recurrence, post-stroke MI, and composite cardiovascular events (stroke and MI). Subgroup analyses were conducted for ischemic stroke etiology. Lp(a) levels were categorized into thresholds (≥30, ≥50, and ≥70 mg/dL). Results: A total of 210 patients were included: mean age was 51.96±15.08 years, 109 (52%) were females, 126 (60%) White, and 79 (38%) Black. The median Lp(a) level was 22.35 mg/dL [IQR: 6.00-75.75]. The median interval between index stroke and Lp(a) testing was 89 days [IQR:4-701]. Among patients who experienced a subsequent cardiovascular event, the median time from stroke to the next event was 11 months [IQR:4-25]. Lp(a) ≥70 mg/dL was significantly associated with a higher number of lifetime recurrent strokes (Incidence Rate Ratio [IRR] =1.55; 95%CI: 1.01-2.37; p=0.047). Elevated Lp(a) levels ≥50 and ≥70 mg/dL were associated with small vessel disease (SVD) etiology (ORs: 2.85 [1.14-7.13], p=0.025; and 2.57 [1.03-6.38], p=0.043). Lp(a) ≥50 mg/dL was suggestively associated with recurrent stroke count in lifetime (IRR: 4.77 [0.80–28.39], p=0.081) in large artery atherosclerosis (LAA); there were no significant associations with recurrence in other stroke etiologies. Lp(a) ≥50 and ≥70 mg/dL were significantly associated with post-stroke MI (ORs: 10.36 [1.18-90.96], p=0.035; and 6.58 [1.22-35.56], p=0.029). Lp(a) ≥50 mg/dL was significantly associated with an increased risk of post-stroke composite cardiovascular events (OR: 2.37 [1.09-5.15], p=0.03). Conclusion: In this cohort, elevated Lp(a) levels were significantly associated with SVD etiology, recurrent stroke, and post-stroke cardiovascular events. Stroke recurrence may be higher in patients with LAA. These findings highlight the potential clinical utility of Lp(a) as a biomarker for risk stratification in stroke survivors and support further investigation into the benefits of Lp(a)-lowering strategies.