Dataset Information

Associations between vascular risk factors and brain MRI indices in UK Biobank.

ABSTRACT: AIMS:Several factors are known to increase risk for cerebrovascular disease and dementia, but there is limited evidence on associations between multiple vascular risk factors (VRFs) and detailed aspects of brain macrostructure and microstructure in large community-dwelling populations across middle and older age. METHODS AND RESULTS:Associations between VRFs (smoking, hypertension, pulse pressure, diabetes, hypercholesterolaemia, body mass index, and waist-hip ratio) and brain structural and diffusion MRI markers were examined in UK Biobank (N?=?9722, age range 44-79?years). A larger number of VRFs was associated with greater brain atrophy, lower grey matter volume, and poorer white matter health. Effect sizes were small (brain structural R2 ?1.8%). Higher aggregate vascular risk was related to multiple regional MRI hallmarks associated with dementia risk: lower frontal and temporal cortical volumes, lower subcortical volumes, higher white matter hyperintensity volumes, and poorer white matter microstructure in association and thalamic pathways. Smoking pack years, hypertension and diabetes showed the most consistent associations across all brain measures. Hypercholesterolaemia was not uniquely associated with any MRI marker. CONCLUSION:Higher levels of VRFs were associated with poorer brain health across grey and white matter macrostructure and microstructure. Effects are mainly additive, converging upon frontal and temporal cortex, subcortical structures, and specific classes of white matter fibres. Though effect sizes were small, these results emphasize the vulnerability of brain health to vascular factors even in relatively healthy middle and older age, and the potential to partly ameliorate cognitive decline by addressing these malleable risk factors.

SUBMITTER: Cox SR

PROVIDER: S-EPMC6642726 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Associations between vascular risk factors and brain MRI indices in UK Biobank.

Cox Simon R SR Lyall Donald M DM Ritchie Stuart J SJ Bastin Mark E ME Harris Mathew A MA Buchanan Colin R CR Fawns-Ritchie Chloe C Barbu Miruna C MC de Nooij Laura L Reus Lianne M LM Alloza Clara C Shen Xueyi X Neilson Emma E Alderson Helen L HL Hunter Stuart S Liewald David C DC Whalley Heather C HC McIntosh Andrew M AM Lawrie Stephen M SM Pell Jill P JP Tucker-Drob Elliot M EM Wardlaw Joanna M JM Gale Catharine R CR Deary Ian J IJ

European heart journal 20190701 28

<h4>Aims</h4>Several factors are known to increase risk for cerebrovascular disease and dementia, but there is limited evidence on associations between multiple vascular risk factors (VRFs) and detailed aspects of brain macrostructure and microstructure in large community-dwelling populations across middle and older age.<h4>Methods and results</h4>Associations between VRFs (smoking, hypertension, pulse pressure, diabetes, hypercholesterolaemia, body mass index, and waist-hip ratio) and brain str ...[more]

PMID: 30854560

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Dataset Information

Associations between vascular risk factors and brain MRI indices in UK Biobank.

Publications

Associations between vascular risk factors and brain MRI indices in UK Biobank.

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