The University of Southampton
University of Southampton Institutional Repository

Small vessel disease pathological changes in neurodegenerative and vascular dementias concomitant with autonomic dysfunction

Small vessel disease pathological changes in neurodegenerative and vascular dementias concomitant with autonomic dysfunction
Small vessel disease pathological changes in neurodegenerative and vascular dementias concomitant with autonomic dysfunction
Autonomic dysfunction may affect brain blood flow and result in intermittent cerebral hypoperfusion, which is recognised as a cause of cognitive impairment and dementia. We assessed the burden of small vessel disease pathology in elderly subjects who had clinical evidence of autonomic dysfunction and had developed neurodegenerative dementias or vascular dementia (VaD). Clinical and neuropathological diagnosis in 118 subjects comprised dementia with Lewy bodies (DLB), Parkinson’s disease with dementia, Alzheimer’s disease (AD), Mixed dementia (mostly AD and DLB), VaD and ageing controls without significant pathology. Autonomic dysfunction was diagnosed in demented subjects who had clinical evidence of carotid sinus hypersensitivity or orthostatic hypotension or both. A subgroup of elderly demented subjects, who were reported to have unexplained falls in life were also analysed in parallel. Post-mortem brain tissues were stained using routine histopathological and immunocytochemical methods to quantify brain vascular and neurodegenerative lesions including hyperphosphorylated tau and α-synuclein. The frontal lobe grey and white matter (WM) in all cases was further assessed to quantify the degree of arteriolosclerosis using the sclerotic index (SI), microvascular density and capillary width using markers of the basement membrane (collagen IV; COL4) and the endothelium (glucose transporter-1; GLUT-1). We found moderate to severe vascular lesions and high vascular pathology scores (P<0.01) in all neurodegenerative dementias and as expected in VaD. Perivascular spacing and microinfarcts were frequently present in the basal ganglia and frontal WM across all dementias whereas lacunes and small infarcts being largely restricted to VaD. We also noted that vascular pathology scores were correlated with WM hyperintensity volumes in dementia subjects who were MR scanned in life (P<0.01). Compared to similar age controls, SI values were increased by ~50% in both the WM and neocortex in all dementias. Whereas COL4 and GLUT-1 immunopositive microvascular densities were decreased in the WM and the cortex of dementia subjects, we found that capillaries were significantly wider by 20-25% in the WM compared to the neocortex irrespective of the type of dementia. Compered to ageing controls, WM capillary widths were remarkably increased in all dementias with autonomic dysfunction (P<0.01). Previous studies suggested that α-synuclein pathology is a strong factor in autonomic dysfunction but we found no clear evidence for this in neurodegenerative dementias or VaD, especially that the burden of α-synuclein pathology in AD and VaD subjects with clinical evidence of autonomic dysfunction was rather low. Overall, our findings demonstrate the presence of widespread small vessel disease (SVD) type of changes in elderly subjects with autonomic dysfunction who develop neurodegenerative dementia. These SVD changes do not necessarily manifest as overt neurological signs but likely confound motor function as well as contribute to the dementia syndrome. Autonomic dysfunction may promote chronic cerebral hypoperfusion to also impact on ongoing neurodegenerative processes and produce the end-stage clinical syndrome.
1015-6305
Hase, Yoshiki
71f7e706-c74d-4e95-9890-a96a373b1507
Polvikoski, Tuomo M.
d6e77327-416a-4253-b1c8-e0949dd5bc26
Firbank, Michael J.
fb7450c5-2499-4a7c-a037-5bba77827ad2
Craggs, Lucinda J.L.
307db0bd-1727-49d0-bf5e-5b1b37a11eb9
Hawthorne, Emily
74a22e3c-4aa1-499e-9b13-8f65b32073c1
Platten, Charlotte
5e513c20-2769-4c21-a3a0-6dd185c7a67a
Stevenson, William
24d03b77-e318-4779-8ca8-be00e7cd80f8
Deramecourt, Vincent
e2337eec-7eeb-4bd5-83f6-ffddee38d778
Ballard, Clive
e244c4e5-5dd4-4c66-9efb-6bf2006bdb7e
Kenny, Rose Anne
7eef3993-1b88-4815-afa5-0397fa8f0745
Perry, Robert H.
84e6f6de-d033-4eff-a2d2-2dce8c131f6e
Ince, Paul
bf15554a-8c61-4aae-ad9e-75127d6d21ea
Carare, Roxana O.
0478c197-b0c1-4206-acae-54e88c8f21fa
Allan, Louise M.
8275b26a-d82e-42dc-844a-91896268349a
Horsburgh, Karen
1bba1a89-7a12-471f-b229-c3633e1a1a57
Kalaria, Raj N.
234141f1-080d-42b0-86c1-51b163ee16f8
Hase, Yoshiki
71f7e706-c74d-4e95-9890-a96a373b1507
Polvikoski, Tuomo M.
d6e77327-416a-4253-b1c8-e0949dd5bc26
Firbank, Michael J.
fb7450c5-2499-4a7c-a037-5bba77827ad2
Craggs, Lucinda J.L.
307db0bd-1727-49d0-bf5e-5b1b37a11eb9
Hawthorne, Emily
74a22e3c-4aa1-499e-9b13-8f65b32073c1
Platten, Charlotte
5e513c20-2769-4c21-a3a0-6dd185c7a67a
Stevenson, William
24d03b77-e318-4779-8ca8-be00e7cd80f8
Deramecourt, Vincent
e2337eec-7eeb-4bd5-83f6-ffddee38d778
Ballard, Clive
e244c4e5-5dd4-4c66-9efb-6bf2006bdb7e
Kenny, Rose Anne
7eef3993-1b88-4815-afa5-0397fa8f0745
Perry, Robert H.
84e6f6de-d033-4eff-a2d2-2dce8c131f6e
Ince, Paul
bf15554a-8c61-4aae-ad9e-75127d6d21ea
Carare, Roxana O.
0478c197-b0c1-4206-acae-54e88c8f21fa
Allan, Louise M.
8275b26a-d82e-42dc-844a-91896268349a
Horsburgh, Karen
1bba1a89-7a12-471f-b229-c3633e1a1a57
Kalaria, Raj N.
234141f1-080d-42b0-86c1-51b163ee16f8

Hase, Yoshiki, Polvikoski, Tuomo M., Firbank, Michael J., Craggs, Lucinda J.L., Hawthorne, Emily, Platten, Charlotte, Stevenson, William, Deramecourt, Vincent, Ballard, Clive, Kenny, Rose Anne, Perry, Robert H., Ince, Paul, Carare, Roxana O., Allan, Louise M., Horsburgh, Karen and Kalaria, Raj N. (2019) Small vessel disease pathological changes in neurodegenerative and vascular dementias concomitant with autonomic dysfunction. Brain Pathology. (doi:10.1111/bpa.12769).

Record type: Article

Abstract

Autonomic dysfunction may affect brain blood flow and result in intermittent cerebral hypoperfusion, which is recognised as a cause of cognitive impairment and dementia. We assessed the burden of small vessel disease pathology in elderly subjects who had clinical evidence of autonomic dysfunction and had developed neurodegenerative dementias or vascular dementia (VaD). Clinical and neuropathological diagnosis in 118 subjects comprised dementia with Lewy bodies (DLB), Parkinson’s disease with dementia, Alzheimer’s disease (AD), Mixed dementia (mostly AD and DLB), VaD and ageing controls without significant pathology. Autonomic dysfunction was diagnosed in demented subjects who had clinical evidence of carotid sinus hypersensitivity or orthostatic hypotension or both. A subgroup of elderly demented subjects, who were reported to have unexplained falls in life were also analysed in parallel. Post-mortem brain tissues were stained using routine histopathological and immunocytochemical methods to quantify brain vascular and neurodegenerative lesions including hyperphosphorylated tau and α-synuclein. The frontal lobe grey and white matter (WM) in all cases was further assessed to quantify the degree of arteriolosclerosis using the sclerotic index (SI), microvascular density and capillary width using markers of the basement membrane (collagen IV; COL4) and the endothelium (glucose transporter-1; GLUT-1). We found moderate to severe vascular lesions and high vascular pathology scores (P<0.01) in all neurodegenerative dementias and as expected in VaD. Perivascular spacing and microinfarcts were frequently present in the basal ganglia and frontal WM across all dementias whereas lacunes and small infarcts being largely restricted to VaD. We also noted that vascular pathology scores were correlated with WM hyperintensity volumes in dementia subjects who were MR scanned in life (P<0.01). Compared to similar age controls, SI values were increased by ~50% in both the WM and neocortex in all dementias. Whereas COL4 and GLUT-1 immunopositive microvascular densities were decreased in the WM and the cortex of dementia subjects, we found that capillaries were significantly wider by 20-25% in the WM compared to the neocortex irrespective of the type of dementia. Compered to ageing controls, WM capillary widths were remarkably increased in all dementias with autonomic dysfunction (P<0.01). Previous studies suggested that α-synuclein pathology is a strong factor in autonomic dysfunction but we found no clear evidence for this in neurodegenerative dementias or VaD, especially that the burden of α-synuclein pathology in AD and VaD subjects with clinical evidence of autonomic dysfunction was rather low. Overall, our findings demonstrate the presence of widespread small vessel disease (SVD) type of changes in elderly subjects with autonomic dysfunction who develop neurodegenerative dementia. These SVD changes do not necessarily manifest as overt neurological signs but likely confound motor function as well as contribute to the dementia syndrome. Autonomic dysfunction may promote chronic cerebral hypoperfusion to also impact on ongoing neurodegenerative processes and produce the end-stage clinical syndrome.

Text
Autonomic dysfunction in Dementia_Brain Pathology_2019 ACCEPTED - Accepted Manuscript
Download (2MB)

More information

Accepted/In Press date: 23 July 2019
e-pub ahead of print date: 29 July 2019

Identifiers

Local EPrints ID: 432942
URI: http://eprints.soton.ac.uk/id/eprint/432942
ISSN: 1015-6305
PURE UUID: 5ed547a4-7e25-448b-8655-6f172e12d021
ORCID for Roxana O. Carare: ORCID iD orcid.org/0000-0001-6458-3776

Catalogue record

Date deposited: 01 Aug 2019 16:30
Last modified: 11 May 2024 04:02

Export record

Altmetrics

Contributors

Author: Yoshiki Hase
Author: Tuomo M. Polvikoski
Author: Michael J. Firbank
Author: Lucinda J.L. Craggs
Author: Emily Hawthorne
Author: Charlotte Platten
Author: William Stevenson
Author: Vincent Deramecourt
Author: Clive Ballard
Author: Rose Anne Kenny
Author: Robert H. Perry
Author: Paul Ince
Author: Louise M. Allan
Author: Karen Horsburgh
Author: Raj N. Kalaria

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×