Abstract W P121: Patterns Of Vessel Involvement In Patients With Intracranial Atherosclerosis Across Ages

Introduction: Intracranial atherosclerosis has been well studied in the aging population, much less is known about atherosclerotic stenosis in the young. Clinicians seek to control traditional vascular risk factors in this population, but differences in patterns of stenosis may call for varied treatment approaches. This study sought to compare age to the distribution of vessel involvement in patients with moderate-severe intracranial stenosis. Methods: This is a retrospective cohort study of patients with intracranial stenosis seen in the stroke clinic of a tertiary center from 2008-2013. Inclusion criteria were moderate-severe intracranial stenosis clinically felt to be due to atherosclerosis with ≥3 traditional vascular risk factors. Patients with other mechanisms of intracranial stenosis were excluded. Stenosis location and severity were based on cerebral angiography, CTA, or MRA. Patients were divided into young ( 65 yr). All 69 patients ≤50 yr were included; a random sample of 69 patients > 50 were selected for this analysis. Results: There were similar rates of vascular risk factors except HTN, which was less common in the young group (81.2% young, 100% middle, 96.8% older, p=0.0006). The location of stenoses varied by age category. Older patients had more posterior circulation involvement compared to the younger groups (p = 0.046), with more frequent involvement of vertebral and basilar arteries (p = 0.012) (Table). The occurrence of stenosis in the distal ICA and MCA vessels were similar among age groups. The frequency of ACA stenosis was highest in the young category (p = 0.026). Conclusion: There are differences in anatomic locations of presumed intracranial atherosclerosis across age groups with older patients (> 65 yrs) having a higher rate of posterior circulation disease. This suggests potential differences in pathophysiological mechanisms. These findings warrant further investigation.