Sex Differences In Non-Stenotic Carotid Plaque Burden Among Patients With ESUS

Background: Sex differences in patients with embolic stroke of undetermined source (ESUS) and non-stenotic internal carotid artery (ICA) plaque have not been reported. Non-stenotic ICA plaque has been identified in patients with ESUS, is inversely proportional to cardioembolic stroke risk in our cohort, and could represent a stroke mechanism in these patients. Sex differences have been observed in patients with stroke and stenotic ICA plaque. Thus, we examined whether sex differences were present in a cohort of patients with ESUS and non-stenotic plaque. Methods: A retrospective multicenter cohort of consecutive patients with ESUS was queried (2015-2021). Patients with unilateral, anterior circulation ESUS who had a CTA neck scan and a transthoracic echocardiogram (TTE) were included. Multiple linear regression was used to model independent contributors to thicker ipsilateral plaque. Results: Of the 273 included patients with unilateral anterior ESUS and adequate TTE or TEE, 133 (49%) were women. While vascular profiles were largely similar, women were older but had less significant ipsilateral plaque compared to men (Table). After adjustment for independent predictors of greater ipsilateral plaque, female sex remained strongly and independently protective against plaque thickness (β -0.46, 95%CI -0.83- -0.09), while older age (β 0.03/yr, 95%CI 0.01-0.04), tobacco use (β 0.38, 95%CI 0.002-0.76), and coronary artery disease (β 0.46, 95%CI -0.05 - 0.97) were associated with thicker ICA plaque. Conclusion: Non-stenotic ICA plaque may contribute to ESUS, but it is less common in women than men. Further investigation of factors that might account for this difference, such as hormonal factors, is warranted. Table.