ABSTRACT NUMBER: ESOC2026A634 POLYVASCULAR BURDEN DEFINES A VASCULAR PHENOTYPE ASSOCIATED WITH WORSE FUNCTIONAL OUTCOME AFTER ISCHEMIC STROKE

Abstract Background and aims Post-stroke prognosis is mainly guided by neurological severity, while cumulative systemic vascular disease burden is rarely considered. Atherosclerotic involvement across multiple vascular territories may define a polyvascular phenotype influencing recovery beyond stroke severity. We assessed whether polyvascular burden is associated with functional and patient-reported outcomes after ischemic stroke and explored its relevance for phenotype-guided secondary prevention. Methods We analyzed a prospective cohort of patients with transient ischemic attack or mild-to-moderate ischemic stroke who underwent systematic vascular assessment during index hospitalization. Polyvascular burden was defined as the number of affected vascular territories: coronary artery disease, extracranial and intracranial atherosclerosis, cerebral small vessel disease, abdominal aortic aneurysm, and peripheral arterial disease. Patients were classified as low (0–1), moderate (2–3), or high (≥4) burden. The primary outcome was 3-month modified Rankin Scale (mRS). Group differences were tested non-parametrically, and adjusted ordinal regression controlled for age, baseline NIHSS, premorbid mRS, and atrial fibrillation. Bayesian ordinal regression was additionally performed. Results Among 94 patients, 62% had low, 33% moderate, and 5% high vascular burden. Functional outcome differed across burden groups (median mRS: 1, 2, and 2; p=0.033). Increasing polyvascular burden was associated with worse 3-month mRS (common OR ≈1.4 per additional vascular territory). Bayesian analysis showed a 97.6% posterior probability that polyvascular burden worsens mRS. Conclusions Polyvascular burden defines a clinically relevant vascular phenotype associated with worse post-stroke recovery, independent of neurological severity, supporting phenotype-guided secondary prevention beyond neurological assessment alone. Conflict of interest JS: nothing to disclose, PS: nothing to disclose, DJ: nothing to disclose, SC: nothing to disclose