Prevalence and effects of lobar microhemorrhages in early-stage dementia.
BACKGROUND
80-100% of patients with Alzheimer's disease have vascular pathology related to cerebral amyloid angiopathy (CAA), and 5-7% have CAA-related lobar microhemorrhages (LMH) at autopsy. The prevalence and effects of LMH detectable by gradient echo MRI (GE-MRI) in early-stage dementia are unknown.


OBJECTIVE
To obtain, using GE-MRI, a prevalence estimate for LMH in patients with early-stage dementia and to assess the effects of LMH on dementia severity.


METHODS
Eighty-four subjects aged >or=55 years (range 58-89; mean 76) underwent cognitive and GE-MRI evaluation. The 84 subjects consisted of 61 consecutive subjects evaluated as part of an initial clinical evaluation for dementia and 23 consecutively evaluated healthy older subjects (controls). Data were analyzed for presence and number of LMH on GE-MRI and the effect of number of LMH on dementia severity.


RESULTS
Nine (15%) of the 61 dementia patients versus 1 (4%) of the 23 control subjects demonstrated LMH on GE-MRI. Multiple (>or=2) LMH were found in 7 of the 9 (88%) dementia subjects with LMH (range of LMH counts 1-330) and no (0%) control subjects. Multivariable causal modeling indicated that number of LMH (p < 0.02), age (p < 0.01) and duration of symptoms (p < 0.001) significantly increased dementia severity while higher educational level (p < 0.001) was protective.


CONCLUSIONS
LMH were detected by GE-MRI in 15% of patients with early-stage dementia and may contribute to dementia severity.
Atri
Alireza
A
Department of Neurology, Massachusetts General Hospital, Boston, MA, USA. aatri@partners.org
Locascio
Joseph J
JJ
Lin
Jenny M
JM
Yap
Liang
L
Dickerson
Bradford C
BC
Grodstein
Francine
F
Irizarry
Michael C
MC
Growdon
John H
JH
Greenberg
S M
SM
D000368:Aged; D000369:Aged, 80 and over; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology*; D003704:Dementia / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009726:Nurses; D011569:Psychiatric Status Rating Scales; D014463:Ultrasonography