Independent value added by diffusion MRI for prediction of cognitive function in older adults.
The purpose of this study was to determine whether white matter microstructure measured by diffusion magnetic resonance imaging (dMRI) provides independent information about baseline level or change in executive function (EF) or memory (MEM) in older adults with and without cognitive impairment. Longitudinal data was acquired from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study from phases GO and 2 (2009-2015). ADNI participants included were diagnosed as cognitively normal (n = 46), early mild cognitive impairment (MCI) (n = 48), late MCI (n = 29), and dementia (n = 39) at baseline. We modeled the association between dMRI-based global white matter mean diffusivity (MD) and baseline level and change in EF and MEM composite scores, in models controlling for baseline bilateral hippocampal volume, regional cerebral FDG PET metabolism and global cerebral AV45 PET uptake. EF and MEM composite scores were measured at baseline, 6, 12, 24 and 36 months. In the baseline late MCI and dementia groups, greater global MD was associated with lesser baseline EF, but not EF change nor MEM baseline or change. As expected, lesser hippocampal volume and lesser FDG PET metabolism was associated with greater rates of EF and MEM decline. In ADNI-GO/2 participants, white matter integrity provided independent information about current executive function, but was not sensitive to future cognitive change. Since individuals experiencing executive function declines progress to dementia more rapidly than those with only memory impairment, better biomarkers of future executive function decline are needed.
University of California Davis, Davis, CA, USA.
Julia A
JA
Scott
University of California San Francisco, San Francisco, CA, USA.
Duygu
D
Tosun
University of Southern California, Los Angeles, CA, USA.
Meredith N
MN
Braskie
University of California Davis, Davis, CA, USA.
Pauline
P
Maillard
University of Southern California, Los Angeles, CA, USA.
Paul M
PM
Thompson
University of California San Francisco, San Francisco, CA, USA.
Michael
M
Weiner
University of California Davis, Davis, CA, USA.
Charles
C
DeCarli
Pennington Biomedical Research Center, Baton Rouge, LA, USA.
Owen T
OT
Carmichael
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000134:cerebrospinal fluid; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid; D060825:Cognitive Dysfunction / Q000134:cerebrospinal fluid / Q000000981:diagnostic imaging*; D003704:Dementia / Q000000981:diagnostic imaging; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D056344:Executive Function / Q000502:physiology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D010446:Peptide Fragments / Q000134:cerebrospinal fluid; D049268:Positron-Emission Tomography; D025341:Principal Component Analysis; D012044:Regression Analysis
D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42); D019788:Fluorodeoxyglucose F18
DTI; Dementia; Executive function; Mild cognitive impairment; White matter integrity