White matter hyperintensities, incident mild cognitive impairment, and cognitive decline in old age

Abstract

ObjectiveExamine the association of white matter hyperintensities (WMH) with risk of incident mild cognitive impairment (MCI) and rate of decline in multiple cognitive systems in community‐based older persons.MethodsParticipants (n = 354) were older persons initially free of cognitive impairment from two ongoing longitudinal epidemiologic studies of aging. All underwent brain magnetic resonance imaging (MRI) for quantification of WMH and gray matter volumes and detailed annual clinical evaluations including 17 cognitive tests. Proportional hazards models were used to examine the relationship between WMH and incident MCI, and mixed‐effects models were used to examine the relationship between WMH and decline in global cognition and five specific cognitive systems.ResultsDuring up to about 6 years of follow‐up (mean = 4.1), 106 (30% of 354) persons developed MCI. In a proportional hazards model adjusted for age, gender, and education, WMH volume was associated with a substantially increased risk of MCI (P < 0.001). Thus, a person with a high WMH volume (90th percentile) was about 2.7 times more likely to develop MCI compared to a person with a low volume (10th percentile). WMH volume also was associated with an increased rate of decline in global cognition (P < 0.001), perceptual speed, working memory, episodic memory, and semantic memory. Associations persisted after adjustment for total gray matter volume, vascular risk factors, and vascular diseases.Interpretation WMH contribute to the development of MCI and are associated with progressive decline in multiple cognitive systems in old age.

Associations between handgrip strength and mild cognitive impairment in middle‐aged and older adults in six low‐ and middle‐income countries

“…[6][7][8] Changes in the performance of motor tasks (eg, handgrip strength and gait) have been associated with changes in cognition and are a harbinger of impending cognitive decline. 6 Second, white matter hyperintensities, which are a common neuropathological characteristic of MCI, 10 have been associated with greater cognitive 10 and muscular mass decline 11 and slowing of gait speed. First, both cognitive and motor performance rely upon the nervous system to execute physical activities; thus, any deficit in the nervous system may result in deficits in cognitive and motor functioning.…”

Total cerebral small vessel disease score and cognitive performance in community‐dwelling older adults. Results from the Atahualpa Project

“…Neuroimaging signatures of SVD include white matter hyperintensities (WMH) of presumed vascular origin, deep cerebral microbleeds (CMB), lacunar infarctions (LI), and enlarged perivascular spaces (PVS). These MRI findings alone or in combination have been individually related to cognitive decline (Arboix, 2011;Wardlaw et al, 2013;Akoudad et al, 2016;Boyle et al, 2016;Arba et al, 2017). The SVD score was developed to address the combined effect of these imaging markers, and those may be a better prediction of cognitive performance (Huijts et al, 2013;Staals et al, 2015;Uiterwijk et al, 2016).…”

Visceral obesity relates to deep white matter hyperintensities via inflammation

“…2,3 A major risk factor for WMH beyond older age is hypertension, 4 in particular, higher systolic blood pressure. 11,12 Research over the past 30 years has reached consensus that most WMH are attributed to cerebral small-vessel disease, 13 referring to pathologies such as arteriosclerosis, amyloid angiopathy, and blood-brain barrier breakdown affecting small cerebral arteries, arterioles, venules, and capillaries. 10 Longitudinal cohort data indicate that WMH load is associated with higher risk of cognitive decline, dementia, and stroke.…”

“…10 Longitudinal cohort data indicate that WMH load is associated with higher risk of cognitive decline, dementia, and stroke. 11,12 Research over the past 30 years has reached consensus that most WMH are attributed to cerebral small-vessel disease, 13 referring to pathologies such as arteriosclerosis, amyloid angiopathy, and blood-brain barrier breakdown affecting small cerebral arteries, arterioles, venules, and capillaries. 14 These vascular pathologies eventually lead to tissue damage that can impact brain function, histologically evident as (incomplete or complete) infarcts, demyelination, loss of oligodendrocytes, and/or axonal damage.…”