Characteristics, risk factors, and mortality of stroke in polycythemia vera: A single-center cohort study from Qatar.

e18591 Background: Polycythemia vera (PV) is a myeloproliferative neoplasm associated with a heightened risk of thrombotic events, including stroke. This study examines the demographic, clinical, and treatment characteristics of PV patients with stroke, comparing them to non-stroke PV patients and focusing on age-specific differences. Methods: A retrospective cohort of 101 PV patients was analyzed for demographic factors, thrombotic events, stroke subtypes, severity, ischemic stroke patterns, and treatment outcomes. Comparative analysis was conducted between stroke and non-stroke PV patients. Results: Stroke occurred in 12% (12/101) of PV patients, with ischemic stroke comprising 83%, one hemorrhagic event (8%), and one cerebral venous thrombosis (8%). The mean age of stroke patients was 51.4 ± 10.1 years (median: 50), and all were JAK2-positive, with 40% initially categorized as low-risk. Stroke severity was mild (NIHSS 0-4) in 64% of cases, predominantly affecting the anterior circulation (80%). Lacunar infarctions were the most common ischemic stroke pattern (50%), followed by embolic and watershed patterns. Stroke prevalence was higher in patients aged ≥40 years (7%) compared to those <40 years (3%; p=0.063). Antithrombotic therapy, primarily aspirin, was administered in 90% of patients, although none received thrombolysis or thrombectomy. Stroke patients were older, demonstrated a higher thrombotic burden, and experienced worse outcomes compared to non-stroke PV patients. Mortality in stroke patients reached 17%, significantly exceeding both the 4% rate in non-stroke PV patients and the general stroke population in Qatar (3.2% for ischemic and 12.6% for hemorrhagic strokes). Conclusions: Stroke represents a significant complication in PV, particularly in patients aged ≥40 years. Ischemic stroke is the predominant subtype, with lacunar infarctions being most common. Despite favorable functional outcomes in most cases, the elevated mortality rate underscores the need for improved risk stratification and tailored antithrombotic strategies to reduce stroke-related complications in PV patients.