Supplementary Material for: Prevalence and Associated Factors of Extracranial Carotid Stenosis in Northern Vietnam Patients with Transient Ischemic Attack or Ischemic Stroke

Background:
In Vietnam, the incidence of transient ischemic attack (TIA) or ischemic stroke has increased in recent years due to lifestyle changes. Carotid stenosis is a common cause of TIA/ischemic stroke. This study aimed to determine the prevalence and identify risk factors for ipsilateral internal carotid artery (ICA) stenosis in patients with transient ischemic attack (TIA) or ischemic stroke.
Methods:
We recruited consecutive patients admitted to Bach Mai hospital from 06/2021 to 06/2022 with the diagnosis of TIA/ischemic stroke. The primary outcome was the presence of significant ipsilateral carotid stenosis (≥50%) by using carotid imaging modalities (duplex ultrasonography, computed tomography angiography or magnetic resonance angiography). Univariable and multivariable logistic regression analyses were performed to identify risk factors associated with 50-99% ICA stenosis.
Results:
In total, 1191 consecutive patients with TIA/ischemic stroke were included. Of these, 62 (5.2%, 95% confidence interval (CI): 4.0-6.6) had 50–99% ipsilateral ICA stenosis. Patients with significant ICA stenosis were more likely to have advanced age, male sex and prior stroke. In multivariable logistic regression, advanced age (OR 1.49 per 10-year increment; CI 95%: 1.17 -1.90, p= 0,001), male sex (OR 4.94 ; CI 95%: 2.15 – 11.38, p < 0.001), and prior stroke (OR 2.01; CI 95%: 1.12 -3.62, p = 0.02) were risk factors for ICA stenosis.
Conclusion:
The observed prevalence of extracranial ICA stenosis in TIA/ischemic stroke patients in Vietnam appears to be lower compared to Western nations, yet it is relatively comparable to that of other Asian countries. Male sex, prior stroke and advanced age constitute significant risk factors for symptomatic ICA stenosis.