TY - JOUR
T1 - Cerebral White Matter Integrity in Amnestic Mild Cognitive Impairment
T2 - A 1-Year Randomized Controlled Trial of Aerobic Exercise Training
AU - Tarumi, Takashi
AU - Thomas, Binu P.
AU - Tseng, Benjamin Y.
AU - Wang, Ciwen
AU - Womack, Kyle B.
AU - Hynan, Linda
AU - Lu, Hanzhang
AU - Cullum, C. Munro
AU - Zhang, Rong
N1 - Publisher Copyright:
© 2020 - IOS Press and the authors. All rights reserved.
PY - 2020
Y1 - 2020
N2 - Cerebral white matter (WM) represents the structural substrate of neuronal communications which is damaged by Alzheimer's disease (AD). Aerobic exercise training (AET) may improve WM integrity in cognitively normal older adults, but its efficacy remains unknown in patients with amnestic mild cognitive impairment (MCI), a prodromal phase of AD dementia. Therefore, we conducted a proof-of-concept study that randomized 70 amnestic MCI patients to a 1-year program of AET or a non-aerobic stretching and toning (SAT), active control group. Thirty-six patients completed both baseline and follow-up MRI scans, and cerebral WM integrity was measured by WM lesion volume and diffusion characteristics using fluid-attenuated-inversion-recovery and diffusion tensor imaging respectively. Peak oxygen uptake (VO2peak) and neuropsychological function were also measured. At baseline and 1-year follow-up, WM lesion volume and diffusion characteristics were similar between the AET and SAT groups, although VO2peak significantly improved after AET. The AET group showed slight improvement in neuropsychological performance. When analyzing individual data, tract-based spatial statistics demonstrated that VO2peak improvements are associated with attenuated elevations in mean and axial diffusivities, particularly the anterior WM fiber tracts (e.g., genu of corpus callosum). In patients with amnestic MCI, we found that although AET intervention did not improve WM integrity at group level analysis, individual cardiorespiratory fitness gains were associated with improved WM tract integrity of the prefrontal cortex.
AB - Cerebral white matter (WM) represents the structural substrate of neuronal communications which is damaged by Alzheimer's disease (AD). Aerobic exercise training (AET) may improve WM integrity in cognitively normal older adults, but its efficacy remains unknown in patients with amnestic mild cognitive impairment (MCI), a prodromal phase of AD dementia. Therefore, we conducted a proof-of-concept study that randomized 70 amnestic MCI patients to a 1-year program of AET or a non-aerobic stretching and toning (SAT), active control group. Thirty-six patients completed both baseline and follow-up MRI scans, and cerebral WM integrity was measured by WM lesion volume and diffusion characteristics using fluid-attenuated-inversion-recovery and diffusion tensor imaging respectively. Peak oxygen uptake (VO2peak) and neuropsychological function were also measured. At baseline and 1-year follow-up, WM lesion volume and diffusion characteristics were similar between the AET and SAT groups, although VO2peak significantly improved after AET. The AET group showed slight improvement in neuropsychological performance. When analyzing individual data, tract-based spatial statistics demonstrated that VO2peak improvements are associated with attenuated elevations in mean and axial diffusivities, particularly the anterior WM fiber tracts (e.g., genu of corpus callosum). In patients with amnestic MCI, we found that although AET intervention did not improve WM integrity at group level analysis, individual cardiorespiratory fitness gains were associated with improved WM tract integrity of the prefrontal cortex.
KW - Aerobic exercise
KW - cardiorespiratory fitness
KW - diffusion tensor imaging
KW - mild cognitive impairment
KW - white matter integrity
UR - http://www.scopus.com/inward/record.url?scp=85078511129&partnerID=8YFLogxK
U2 - 10.3233/JAD-190875
DO - 10.3233/JAD-190875
M3 - Article
C2 - 31796677
AN - SCOPUS:85078511129
SN - 1387-2877
VL - 73
SP - 489
EP - 501
JO - Journal of Alzheimer's Disease
JF - Journal of Alzheimer's Disease
IS - 2
ER -