Abstract T P362: Prevalence and Clinicoradiological Profile of Japanese Patients with Alzheimer Disease Coexisting Multiple Microbleeds

Abstract

Background: Pathological findings of cerebral amyloid angiopathy (CAA) and Alzheimer’s disease (AD) coexist frequently. Both diseases are associated with β-amyloid deposition and dementia. We aimed to evaluate frequency and clinicoradiological profile of AD patients with multiple microbleeds (MBs) Methods: We reviewed clinical charts and magnetic resonance imaging (MRI) findings in patients with probable AD from 2009 to 2012, according to the DSM-IV. Brain MRI was performed at 1.5 T using protocols, including T2*-weighted gradient-echo or susceptibility-weighted imaging. MBs were defined as rounded, hypointense foci ≤ 10 mm in size in the brain parenchyma. MBs topography was divided into the lobar (L) and the deep/infratentorial (D/I) region. Multiple MBs were defined as the number ≥ 8 in the L or the D/I territory. White matter hyperintensities (WMH) were assessed using the age-related white matter changes scale. Clinicoradiological findings were examined for ≥ 1 year. Prevalence and clinicoradiological profiles were studied in patients with multiple L MBs or multiple D/I MBs. Results: Five hundred fifty patients (238 men and 312 women) were participated in the present study. Mean age (SD) was 78.4 (7.7) years, 78.3 (8.1) in men and 78.6 (7.5) in woman. A total of 132 patients (55 men and 78 women) had at least MB. Prevalence of total MBs was 24.0%, 23.1 in men and 25.0 in women. Multiple L MBs existed in 49 patients (8.9%), 15 men (6.3) and 34 women (10.9). Multiple D/I MBs were found in 44 patients (8.0%), 23 men (9.7) and 21 women (6.7). Clinical profiles of multiple L MBs revealed sudden deterioration, rapid progression, non-hypertension, higher rates of symptomatic subcortical hemorrhage and onset of CAA-associated leukoencephalopathy. Radiological hallmarks exhibited increased number and size of MBs, high score of WMH and asymptomatic subcortical hemorrhage. Clinicoradiological features of multiple D/I MBs exhibited higher rates of hypertension and variable degrees of WMH. Conclusions: The present study indicated that prevalence of multiple MBs was 16.9% in Japanese patients with AD. The clinicoradiological profile suggested severe degree of CAA in patients with multiple L MBs (8.9%) and hypertensive changes in patients with multiple D/I MBs (8.0%).