LAUSR

OBJECTIVE We investigated the characteristics and relationship of co-existing intracranial artery stenosis (ICAS) and extracranial carotid atherosclerosis in an asymptomatic rural population in northern China. METHODS Asymptomatic residents ≥ 30 years old in 13 villages underwent simultaneous cervical vascular and transcranial Doppler ultrasound. ICAS was defined as ≥ 50% stenosis. Extracranial carotid atherosclerosis severity was classified as increased intimal medial thickness (IMT), plaques, and a plaque with ≥ 50% extracranial artery stenosis (ECAS). Demographic details, medical history, and blood biochemistry results were collected. The relationship between ICAS and extracranial carotid atherosclerosis severity was determined using the chi-square trend test and binary logistic regression analysis. RESULTS A total of 2598 asymptomatic participants were included; 122 (4.7%) had ICAS, 1071 (41.2%) had extracranial carotid atherosclerosis, and 84 (3.2%) had co-existing extracranial carotid atherosclerosis and ICAS. Those with co-existing ICAS and extracranial carotid atherosclerosis were older (P = 0.006) and had a higher hypertension (HTN) and diabetes mellitus (DM) prevalence (P < 0.001). HTN (95% confidence interval [CI]=1.31-3.55, odds ratio [OR]=2.15) and DM (95% CI=1.17-4.30, OR=2.24) were found to be independent risk factors for asymptomatic ICAS with extracranial carotid atherosclerosis. Among those with ICAS, 38/122 had no extracranial carotid atherosclerosis, 8/122 had increased IMT, 64/122 had a plaque, and 12/122 had ECAS. As extracranial carotid atherosclerosis severity increases, ICAS prevalence increases. CONCLUSION Co-existing ICAS and extracranial carotid atherosclerosis occurred in 3.2% of asymptomatic populations in rural areas of northern China. As extracranial carotid atherosclerosis severity increased, ICAS prevalence also increased. HTN and DM might be independent indicators of co-existing ICAS and extracranial carotid atherosclerosis.