Associations between amyloid β and white matter hyperintensities: A systematic review.
BACKGROUND
This systematic review synthesizes current evidence for associations between cortical amyloid β, visualized on amyloid positron emission tomography imaging, and white matter hyperintensity (WMH) burden on magnetic resonance imaging in healthy elderly adults and individuals with cognitive impairment and dementia.


METHODS
Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) systematic review guidelines, we systematically searched MEDLINE, Embase, Cochrane, and PsycINFO databases from January 2000 to September 2015.


RESULTS
Our search returned 492 articles, 34 of which met criteria for inclusion in the final selection. Most studies reported no significant relationships between amyloid β and WMH burden across diagnostic groups.


CONCLUSIONS
Findings of this systematic review suggest that amyloid accumulation and WMH are independent but additive processes. The limited number of independent cohorts, lack of longitudinal data, and exclusion of individuals with mixed dementia limit the generalizability of these findings. Further studies are required to elucidate the putative contributions of vascular processes to neurodegenerative pathology.
LC Campbell Cognitive Neurology Research Unit, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Ontario, Canada.
Austyn
A
Roseborough
LC Campbell Cognitive Neurology Research Unit, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Ontario, Canada.|Heart & Stroke Foundation Canadian Partnership for Stroke Recovery, Toronto, Ontario, Canada.
Joel
J
Ramirez
LC Campbell Cognitive Neurology Research Unit, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Ontario, Canada.|Heart & Stroke Foundation Canadian Partnership for Stroke Recovery, Toronto, Ontario, Canada.|Department of Medicine, Neurology, University of Toronto and Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
Sandra E
SE
Black
LC Campbell Cognitive Neurology Research Unit, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Ontario, Canada.|Heart & Stroke Foundation Canadian Partnership for Stroke Recovery, Toronto, Ontario, Canada.
Jodi D
JD
Edwards
D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D006801:Humans; D066127:White Matter / Q000378:metabolism / Q000473:pathology*
D016229:Amyloid beta-Peptides
Alzheimer's disease; Amyloid; Dementia; Systematic review; White matter disease