Intracranial large artery disease in Alzheimer’s disease and vascular dementia among ethnic Asians

Background and purpose: An underlying vascular etiology underpins vascular dementia (VaD) and possibly Alzheimer’s disease (AD). Intracranial large artery disease (ICLAD) is a common site of disease among ethnic Asians, and carries a poor prognosis. We studied the prevalence of ICLAD among ethnic Asian patients with AD and VaD. Methods: We recruited patients with AD and VaD from a retrospective review of consecutive ethnic Asian patients presenting to our dementia clinic. ICLAD was evaluated by visual inspection of brain magnetic resonance angiography by two observers in consensus, and defined as >50% luminal narrowing. Results: There were 56 patients with probable AD and 47 with probable VaD. ICLAD was prevalent among 53% of VaD patients and 18% of AD patients. Conclusions: There is a relatively high burden of ICLAD among AD and VaD patients of Asian ethnicity. We suggest that ethnic Asian dementia patients are a potential group to investigate if ICLAD is associated with clinical symptoms or prognosis and if treatment strategies targeted at ICLAD retard the progression of cognitive impairment.