Abstract:
Background: Large artery atherosclerotic disease is an important cause of stroke, accounting for 15–46% of ischaemic strokes in population-based studies. Therefore, current guidelines from west recommend urgent carotid imaging
in all ischaemic strokes or transient ischaemic attacks and referral for carotid endarterectomy. However, the clinical
features and epidemiology of stroke in Asians are diferent from those in Caucasians and therefore the applicability
of these recommendations to Asians is controversial. Data on the prevalence of carotid artery stenosis (CAS) among
South Asian stroke patients is limited. Therefore, we sought to determine the prevalence and associated factors of
signifcant CAS in a cohort of Sri Lankan patients with ischaemic stroke.
Methods: We prospectively studied all ischaemic stroke patients who underwent carotid doppler ultrasonography admitted to the stroke unit of a Sri Lankan tertiary care hospital over 5 years. We defned carotid stenosis as low
(<50%), moderate (50–69%) or severe (70–99%) or total-occlusion (100%) by North American Symptomatic Trial
Collaborators (NASCET) criteria. We identifed the factors associated with CAS≥50% and≥70% by stepwise multiple
logistic regression analysis.
Results: A total of 550 ischaemic stroke patients (326 (59.3%) male, mean age was 58.9±10.2 years) had carotid
doppler ultrasonography. Of them, 528 (96.0%) had low-grade, 12 (2.2%) moderate and 7 (1.3%) severe stenosis and 3
(0.5%) had total occlusion. On multivariate logistic regression, age was associated with CAS≥50% (OR 1.12, p=0.001)
and CAS≥70% (OR 1.14, p=0.016), but none of the other vascular risk factors studied (sex, hypertension, diabetes
mellitus, smoking, past history of TIA, stroke or ischemic heart disease) showed signifcant associations.
Conclusions: Carotid stenosis is a minor cause of ischemic stroke in Sri Lankans compared to western populations
with only 4.0% having CAS≥50 and 3.5% eligible for carotid endarterectomy. Our fndings have implications for the
management of acute strokes in Sri Lanka.