Incidence of cerebral microbleeds: a longitudinal study in a memory clinic population.
BACKGROUND
Cerebral microbleeds (MBs) are commonly observed in memory clinic patients. Little is known about occurrence of and risk factors for developing new MBs in this population.


OBJECTIVE
To investigate incidence of lobar and nonlobar MBs in a memory clinic population. Furthermore, to assess risk factors for the development of new MBs and their associations with other MRI changes.


METHODS
A total of 254 patients visiting our memory clinic, with repeat gradient-recalled echo T2*-weighted MRI, were included (scan interval 1.9 +/- 0.9 years). Baseline and incident MBs were regionally counted. White matter hyperintensities (WMH) and progression of WMH were assessed using visual rating scales. Baseline brain volume and whole-brain atrophy rate were estimated automatically. In a subset, APOE was determined.


RESULTS
Thirty-one (12%) patients developed new MBs (range 1-19). Both multiple strictly lobar and nonlobar MBs at baseline predicted incident MBs (odds ratio [OR] 8.4; 95% confidence interval [CI] 2.2-33.2, and OR 33.8; 95% CI 8.1-140.8). Furthermore, baseline WMH grade (OR 1.2; 1.1-1.3), lacunar infarcts (OR 2.8; 1.3-6.0), and APOE epsilon2 carriership (OR 4.2; 1.4-12.5) predicted MB incidence. Incident MB patients had more progression of WMH (p < 0.01) and incident lacunar infarcts (p < 0.05). These relations were most prominent for incident nonlobar MBs. Incident strictly lobar MBs were associated with smoking.


CONCLUSIONS
In addition to APOE genotype, presence and progression of small-vessel disease and vascular risk factors were predictors of new MBs. The latter are potentially modifiable, suggesting the possibility of preventing incident MBs, hopefully resulting in slower clinical decline.
Goos
J D C
JD
Alzheimer Center and Department of Neurology, VU University Medical Center, Amsterdam, the Netherlands. j.goos@vumc.nl
Henneman
W J P
WJ
Sluimer
J D
JD
Vrenken
H
H
Sluimer
I C
IC
Barkhof
F
F
Blankenstein
M A
MA
Scheltens
P H
PH
van der Flier
W M
WM
D000368:Aged; D002543:Cerebral Hemorrhage / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008569:Memory Disorders / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital; D012189:Retrospective Studies; D012307:Risk Factors