TY - JOUR
T1 - Cortical and subcortical cerebrovascular resistance index in mild cognitive impairment and Alzheimer's disease
AU - Nation, Daniel A.
AU - Wierenga, Christina E.
AU - Clark, Lindsay R.
AU - Dev, Sheena I.
AU - Stricker, Nikki H.
AU - Jak, Amy J.
AU - Salmon, David P.
AU - Delano-Wood, Lisa
AU - Bangen, Katherine J.
AU - Rissman, Robert A.
AU - Liu, Thomas T.
AU - Bondi, Mark W.
PY - 2013
Y1 - 2013
N2 - Background: Reduced regional cerebral blood flow (rCBF) is a well-established finding in Alzheimer's disease (AD), although fewer studies have examined the role of increased regional cerebrovascular resistance. By calculating the ratio of mean arterial pressure to rCBF, it is possible to estimate an index of regional cerebrovascular resistance (CVRi) that may be a sensitive measure of occult cerebrovascular disease. Objective: To compare probable AD patients to mild cognitive impairment (MCI) and normal control (NC) participants on CVRi, the ratio of mean arterial pressure to rCBF. Methods: Eighty-one participants (12 AD, 23 MCI, 46 NC) were compared on CVRi using voxel-wise analyses. Region-of-interest analyses examined correlations between subcortical CVRi and both cognition and white matter lesion (WML) volume. Results: Voxel-wise analyses revealed CVRi elevation in AD relative to NCs (subcortical, medial temporal, posterior cingulate, precuneus, inferior parietal, superior temporal) and MCI (subcortical, posterior cingulate). MCI participants exhibited intermediate CVRi values within cortical and medial temporal areas. Significant CVRi clusters were larger and more widespread than those of parallel CBF analyses. Among MCI and AD participants, subcortical CVRi elevation was associated with lower Dementia Rating Scale score (r = -0.52, p = 0.001, for both thalamus and caudate), and caudate CVRi correlated with WML volume (r = 0.45, p = 0.001). Conclusions: Cortical and subcortical CVRi is elevated in AD, particularly within the caudate and thalamus, where it is associated with decreased cognitive performance and increased WMLs. Findings suggest CVRi may play a role in cognitive decline and cerebrovascular disease in MCI and AD.
AB - Background: Reduced regional cerebral blood flow (rCBF) is a well-established finding in Alzheimer's disease (AD), although fewer studies have examined the role of increased regional cerebrovascular resistance. By calculating the ratio of mean arterial pressure to rCBF, it is possible to estimate an index of regional cerebrovascular resistance (CVRi) that may be a sensitive measure of occult cerebrovascular disease. Objective: To compare probable AD patients to mild cognitive impairment (MCI) and normal control (NC) participants on CVRi, the ratio of mean arterial pressure to rCBF. Methods: Eighty-one participants (12 AD, 23 MCI, 46 NC) were compared on CVRi using voxel-wise analyses. Region-of-interest analyses examined correlations between subcortical CVRi and both cognition and white matter lesion (WML) volume. Results: Voxel-wise analyses revealed CVRi elevation in AD relative to NCs (subcortical, medial temporal, posterior cingulate, precuneus, inferior parietal, superior temporal) and MCI (subcortical, posterior cingulate). MCI participants exhibited intermediate CVRi values within cortical and medial temporal areas. Significant CVRi clusters were larger and more widespread than those of parallel CBF analyses. Among MCI and AD participants, subcortical CVRi elevation was associated with lower Dementia Rating Scale score (r = -0.52, p = 0.001, for both thalamus and caudate), and caudate CVRi correlated with WML volume (r = 0.45, p = 0.001). Conclusions: Cortical and subcortical CVRi is elevated in AD, particularly within the caudate and thalamus, where it is associated with decreased cognitive performance and increased WMLs. Findings suggest CVRi may play a role in cognitive decline and cerebrovascular disease in MCI and AD.
KW - Alzheimer's disease
KW - cerebral blood flow
KW - cerebrovascular resistance
KW - mild cognitive impairment
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U2 - 10.3233/JAD-130086
DO - 10.3233/JAD-130086
M3 - Article
C2 - 23666173
AN - SCOPUS:84881448946
SN - 1387-2877
VL - 36
SP - 689
EP - 698
JO - Journal of Alzheimer's Disease
JF - Journal of Alzheimer's Disease
IS - 4
ER -