Brain aging comprises many modes of structural and functional change with distinct genetic and biophysical associations
- University of Oxford, United Kingdom
- Simon Fraser University, Canada
Abstract
Brain imaging can be used to study how individuals’ brains are aging, compared against population norms. This can inform on aspects of brain health; for example, smoking and blood pressure can be seen to accelerate brain aging. Typically, a single 'brain age' is estimated per subject, whereas here we we identified 62 modes of subject variability, from 21,407 subjects' multimodal brain imaging data in UK Biobank. The modes represent different aspects of brain aging, showing distinct patterns of functional and structural brain change, and distinct patterns of association with genetics, lifestyle, cognition, physical measures and disease. While conventional brain-age modelling found no genetic associations, 34 modes had genetic associations. We suggest that it is important not to treat brain aging as a single homogeneous process, and that modelling of distinct patterns of structural and functional change will reveal more biologically meaningful markers of brain aging in health and disease.
Data availability
All source data is available from UK Biobank, as described in Section 5. That section also describes the full availability of all of our code used for this work, and additional supplementary materials. https://www.fmrib.ox.ac.uk/ukbiobank/BrainAgingModes/
Article and author information
Author details
Funding
Wellcome (203139/Z/16/Z)
- Stephen M Smith
- Karla L Miller
Wellcome (098369/Z/12/Z)
- Stephen M Smith
Wellcome (215573/Z/19/Z)
- Stephen M Smith
Wellcome (202788/Z/16/Z)
- Karla L Miller
Medical Research Council (MR/K006673/1)
- Gwenaëlle Douaud
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The UK Biobank has approval from the North West Multi-centre Research Ethics Committee (MREC) to obtain and disseminate data and samples from the participants (http://www.ukbiobank.ac.uk/ethics/), and these ethical regulations cover the work in this study. Written informed consent was obtained from all participants.
Copyright
© 2020, Smith et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Brain aging comprises many modes of structural and functional change with distinct genetic and biophysical associations
eLife 9:e52677.
https://doi.org/10.7554/eLife.52677
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