ABSTRACT NUMBER: ESOC2026A2247 PREVALENCE AND RISK FACTOR PROFILE OF NASCET-DEFINED EXTRACRANIAL CAROTID ATHEROSCLEROSIS AMONG STROKE PATIENTS IN A TERTIARY HOSPITAL IN EASTERN NIGERIA

Abstract Background and aims Extracranial carotid atherosclerosis is a recognized and potentially modifiable risk factor for ischemic stroke. This research aims to determine the prevalence and risk factor profile of NASCET-defined extracranial carotid atherosclerosis among stroke patients in a tertiary hospital in eastern Nigeria. Methods This retrospective observational study included adult stroke patients managed between June 2020, and July 2024. Stroke was diagnosed clinically and confirmed by CT or MRI. Extracranial carotid stenosis was assessed using Doppler ultrasonography and graded according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Significant carotid atherosclerosis was defined as ≥50% stenosis. Demographic, clinical, and vascular risk factor data were extracted from medical records. Associations were assessed using chi-square or Fisher’s exact tests. Results Among 332 stroke patients, 55 (16.6%) had significant extracranial carotid stenosis. Right- and left-sided stenosis were observed in 7.8% and 9.3% of participants, respectively. Severe stenosis (≥70%) and carotid occlusion were rare. The study population was predominantly elderly, hypertensive, and diabetic. Most vascular risk factors—including age, sex, hypertension, diabetes mellitus, smoking, alcohol use, lipidemia, and heart disease—were not significantly associated with carotid stenosis. Atrial fibrillation was significantly associated with carotid stenosis (p = 0.005). Conclusions In this cohort, the prevalence of NASCET-defined significant extracranial carotid atherosclerosis among stroke patients was modest, with severe disease being uncommon. Atrial fibrillation emerged as the only vascular risk factor significantly associated with carotid stenosis. These findings underscore the need for context-specific stroke evaluation strategies and support the predominance of non-extracranial large-artery mechanisms of stroke in this population. Conflict of interest Nneoma Paracleta Abajue - Nothing to disclose, Godwin Uchenna Edeh - Nothing to disclose, Mkpoikanabasi Obot-obot - Nothing to disclose, Benjamin Nnadozie Anyanwu - Nothing to disclose