Leveraging longitudinal diffusion MRI data to quantify differences in white matter microstructural decline in normal and abnormal aging

Archer, D. B.; Schilling, K.; Shashikumar, N.; Jasodanand, V.; Moore, E.; Pechman, K.; Bilgel, M.; Beason-Held, L.; An, Y.; Shafer, A.; Ferrucci, L.; Risacher, S. L.; Gifford, K.; Landman, B.; Landman, B. A.; Jefferson, A.; Saykin, A. J.; Resnick, S. M.; Hohman, T.; Alzheimer's Disease Neuroimaging Initiative,

doi:10.1101/2023.05.17.541182

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bioRxiv · 10.1101/2023.05.17.541182

Leveraging longitudinal diffusion MRI data to quantify differences in white matter microstructural decline in normal and abnormal aging

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AbstractO_ST_ABSINTRODUCTIONC_ST_ABSIt is unclear how rates of white matter microstructural decline differ between normal aging and abnormal aging. METHODSDiffusion MRI data from several well-established longitudinal cohorts of aging [Alzheimers Neuroimaging Initiative (ADNI), Baltimore Longitudinal Study of Aging (BLSA), Vanderbilt Memory & Aging Project (VMAP)] was free-water corrected and harmonized. This dataset included 1,723 participants (age at baseline: 72.8{+/-}8.87 years, 49.5% male) and 4,605 imaging sessions (follow-up time: 2.97{+/-}2.09 years, follow-up range: 1-13 years, mean number of visits: 4.42{+/-}1.98). Differences in white matter microstructural decline in normal and abnormal agers was assessed. RESULTSWhile we found global decline in white matter in normal/abnormal aging, we found that several white matter tracts (e.g., cingulum bundle) were vulnerable to abnormal aging. CONCLUSIONSThere is a prevalent role of white matter microstructural decline in aging, and future large-scale studies in this area may further refine our understanding of the underlying neurodegenerative processes. HIGHLIGHTSO_LILongitudinal data was free-water corrected and harmonized C_LIO_LIGlobal effects of white matter decline were seen in normal and abnormal aging C_LIO_LIThe free-water metric was most vulnerable to abnormal aging C_LIO_LICingulum free-water was the most vulnerable to abnormal aging C_LI

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Archer, D. B., Schilling, K., Shashikumar, N., Jasodanand, V., Moore, E., Pechman, K., Bilgel, M., Beason-Held, L., An, Y., Shafer, A., Ferrucci, L., Risacher, S. L., Gifford, K., Landman, B., Landman, B. A., Jefferson, A., Saykin, A. J., Resnick, S. M., Hohman, T., Alzheimer's Disease Neuroimaging Initiative,. 2023-05-18. Leveraging longitudinal diffusion MRI data to quantify differences in white matter microstructural decline in normal and abnormal aging. https://doi.org/10.1101/2023.05.17.541182

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