Li Du, Haiyu Liu, Xiaoke Wang, Yingqi Xing, Xiujuan Wu, Yi Yang, Jun Liu, Kangding Liu, Jie Zhu and Hong-Liang Zhang
Background: Cerebral artery stenosis is an important risk factor for ischemic strokes. Racial predilection with reference to stenosed artery distribution has been recognized. Intracranial artery stenosis was more frequently detected in Asians, blacks and hispanics with ischemic strokes. However, distribution of intraand extra-cranial artery stenosis with reference to age and sex has not been clarified. This study aims to explore intracranial and extracranial artery stenosis in a large northeast Chinese cohort by utilizing transcranial Doppler (TCD) and carotid duplex ultrasound.
Methods: We recruited 14793 outpatients and hospitalized patients to identify artery stenosis distribution. Artery stenosis screening was done with TCD for intracranial arteries and carotid duplex ultrasound for extracranial arteries.
Findings: More patients with intracranial than with extracranial artery stenoses were identified (4255 versus 2809, i.e. 28.8% versus 19.0%, P<0.05). Similarly, mere intracranial stenosis was significantly more common than extracranial artery stenosis in this cohort (2632 versus 1186, i.e. 17.8% versus 8%, P<0.05). Among all identified intracranial arteries stenoses, the proportion of middle cerebral artery (MCA) stenosis was the highest. More intracranial than extracranial artery stenoses was seen within each age group, and rates of both increased with age. Intracranial and/or extracranial artery stenosis was more frequently identified in males than females, and intracranial artery stenosis in both groups was respectively more common compared to extracranial stenosis.
Interpretation: Incidence of cerebral artery stenosis in the population increases with age. Intracranial artery stenosis is more common than extracranial artery stenosis and the MCA stenosis accounted for the highest proportion among cerebral artery stenoses, within each age group. More males suffer from intracranial or extracranial artery stenosis than females.