Interaction of cardiovascular disease and neurodegeneration: transcranial Doppler ultrasonography and Alzheimer's disease.
OBJECTIVE
Recent post-mortem studies have reported that the severity of atheromatous deposits in the circle of Willis is significantly greater, relative to non-demented (ND) elderly persons, in subjects with neuropathologically diagnosed Alzheimer's disease (AD). Additionally, the severity of intracranial atherosclerosis correlates significantly with the densities of neuritic plaques and neurofibrillary tangles. In this study, we examine the arteries of the circle of Willis by transcranial Doppler (TCD) ultrasonography.


METHODS
TCD was used to measure, in 25 AD patients and 30 ND elderly subjects, mean flow velocities and pulsatility indices in 16 different segments of the circle of Willis. The data were compared with and without adjustment for age, gender and systolic blood pressure.


RESULTS
The AD patients had systematically higher pulsatility indices (p<0.005) than the ND group. Incremental increases of pulsatility indices in these segments had odds ratios ranging from 1.8 to 48 for the presence of AD when adjusted for age, gender and systolic blood pressure. The left internal carotid artery siphon and the left posterior cerebral artery were the two vessels that were strongly associated with AD diagnosis. Mean flow velocities were generally lower in patients with AD but the differences did not reach the significance level.


CONCLUSIONS
The pulsatility indices of the arteries of AD patients were generally greater than those of similarly-aged ND subjects. This difference is most likely due to increased arterial wall rigidity imposed by atherosclerotic changes. Atherosclerotic disease of intracranial arteries may be a risk factor for AD.
Roher
Alex E
AE
Longtine Center for Molecular Biology and Genetics, Sun Health Research Institute, Sun City AZ 85351, USA. alex.roher@sunhealth.org
Garami
Zsolt
Z
Alexandrov
Andrei V
AV
Kokjohn
Tyler A
TA
Esh
Chera L
CL
Kalback
Walter M
WM
Vedders
Linda J
LJ
Wilson
Jeffrey R
JR
Sabbagh
Marwan N
MN
Beach
Thomas G
TG
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology*; D020771:Anterior Cerebral Artery / Q000000981:diagnostic imaging; D002318:Cardiovascular Diseases / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology*; D002560:Cerebrovascular Circulation; D002941:Circle of Willis / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D009410:Nerve Degeneration / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology; D020769:Posterior Cerebral Artery / Q000000981:diagnostic imaging; D017585:Ultrasonography, Doppler, Transcranial