ABSTRACT NUMBER: ESOC2026A1048 POST-THROMBOLYSIS LIPOPROTEIN(A) AND THE RISK OF SYMPTOMATIC HEMORRHAGIC TRANSFORMATION IN ACUTE ISCHEMIC STROKE

Abstract Background and aims Lipoprotein(a) [Lp(a)] is a proatherogenic and prothrombotic biomarker, but its association with hemorrhagic transformation (HT) after intravenous thrombolysis with recombinant tissue plasminogen activator (IV tPA) in acute ischemic stroke (AIS) remains unclear. We investigated whether Lp(a) levels are associated with symptomatic HT. Methods This retrospective single-center study included 336 consecutive AIS patients treated with IV tPA between 2020 and 2025. Serum Lp(a) was measured within 24 hours after thrombolysis. Symptomatic HT was defined using the National Institute of NINDS and ECASS III criteria. Lp(a) was analyzed per 10 mg/dL increase and by tertiles. Logistic regression models were unadjusted and adjusted for age, sex, baseline NIHSS score, initial glucose, onset-to-needle time, reperfusion method, and CRP. Results The median age was 70 years, and 61.9% were male. Symptomatic HT occurred in 55 patients (16.4%) by NINDS criteria and 29 (8.6%) by ECASS III criteria. Higher Lp(a) levels were associated with increased HT risk. For NINDS-defined HT, each 10 mg/dL increase in Lp(a) yielded an adjusted odds ratio (OR) of 1.33 (95% CI, 1.17–1.51). Patients in the highest tertile had higher odds of HT than those in the lowest tertile (adjusted OR, 5.97; 95% CI, 2.41–14.80; p for trend < 0.01). Similar results were observed for ECASS III-defined HT (adjusted OR per 10 mg/dL, 1.30; 95% CI, 1.14–1.48; p for trend = 0.02). Conclusions Elevated Lp(a) is associated with symptomatic HT after IV tPA in AIS and identifies bleeding risk. Conflict of interest Nothing to disclose