TY - JOUR
T1 - Vascular risk factors, large-artery atheroma, and brain white matter hyperintensities
AU - Wardlaw, Joanna M
AU - Allerhand, Michael
AU - Doubal, Fergus N
AU - Valdes Hernandez, Maria
AU - Morris, Zoe
AU - Gow, Alan J
AU - Bastin, Mark
AU - Starr, John M
AU - Dennis, Martin S
AU - Deary, Ian J
PY - 2014/4/15
Y1 - 2014/4/15
N2 - OBJECTIVE: To determine the magnitude of potentially causal relationships among vascular risk factors (VRFs), large-artery atheromatous disease (LAD), and cerebral white matter hyperintensities (WMH) in 2 prospective cohorts.METHODS: We assessed VRFs (history and measured variables), LAD (in carotid, coronary, and leg arteries), and WMH (on structural MRI, visual scores and volume) in: (a) community-dwelling older subjects of the Lothian Birth Cohort 1936, and (b) patients with recent nondisabling stroke. We analyzed correlations, developed structural equation models, and performed mediation analysis to test interrelationships among VRFs, LAD, and WMH.RESULTS: In subjects of the Lothian Birth Cohort 1936 (n = 881, mean age 72.5 years [SD ±0.7 years], 49% with hypertension, 33% with moderate/severe WMH), VRFs explained 70% of the LAD variance but only 1.4% to 2% of WMH variance, of which hypertension explained the most. In stroke patients (n = 257, mean age 74 years [SD ±11.6 years], 61% hypertensive, 43% moderate/severe WMH), VRFs explained only 0.1% of WMH variance. There was no direct association between LAD and WMH in either sample. The results were the same for all WMH measures used.CONCLUSIONS: The small effect of VRFs and LAD on WMH suggests that WMH have a large "nonvascular," nonatheromatous etiology. VRF modification, although important, may be limited in preventing WMH and their stroke and dementia consequences. Investigation of, and interventions against, other suspected small-vessel disease mechanisms should be addressed.
AB - OBJECTIVE: To determine the magnitude of potentially causal relationships among vascular risk factors (VRFs), large-artery atheromatous disease (LAD), and cerebral white matter hyperintensities (WMH) in 2 prospective cohorts.METHODS: We assessed VRFs (history and measured variables), LAD (in carotid, coronary, and leg arteries), and WMH (on structural MRI, visual scores and volume) in: (a) community-dwelling older subjects of the Lothian Birth Cohort 1936, and (b) patients with recent nondisabling stroke. We analyzed correlations, developed structural equation models, and performed mediation analysis to test interrelationships among VRFs, LAD, and WMH.RESULTS: In subjects of the Lothian Birth Cohort 1936 (n = 881, mean age 72.5 years [SD ±0.7 years], 49% with hypertension, 33% with moderate/severe WMH), VRFs explained 70% of the LAD variance but only 1.4% to 2% of WMH variance, of which hypertension explained the most. In stroke patients (n = 257, mean age 74 years [SD ±11.6 years], 61% hypertensive, 43% moderate/severe WMH), VRFs explained only 0.1% of WMH variance. There was no direct association between LAD and WMH in either sample. The results were the same for all WMH measures used.CONCLUSIONS: The small effect of VRFs and LAD on WMH suggests that WMH have a large "nonvascular," nonatheromatous etiology. VRF modification, although important, may be limited in preventing WMH and their stroke and dementia consequences. Investigation of, and interventions against, other suspected small-vessel disease mechanisms should be addressed.
KW - Aged
KW - Aged, 80 and over
KW - Arteries
KW - Brain
KW - Dementia
KW - Female
KW - Humans
KW - Magnetic Resonance Imaging
KW - Male
KW - Middle Aged
KW - Nerve Fibers, Myelinated
KW - Plaque, Atherosclerotic
KW - Risk Factors
KW - Vascular Diseases
U2 - 10.1212/WNL.0000000000000312
DO - 10.1212/WNL.0000000000000312
M3 - Article
C2 - 24623838
SN - 0028-3878
VL - 82
SP - 1331
EP - 1338
JO - Neurology
JF - Neurology
IS - 15
ER -