Impaired Glymphatic Flow on Diffusion Tensor MRI as a Marker of Neurodegeneration in Alzheimer's Disease: Correlation with Gray Matter Volume Loss and Cognitive Decline Independent of Cerebral Amyloid Deposition.

Abstract

Background:

Impaired glymphatic flow on the Alzheimer's disease (AD) spectrum may be evaluated using diffusion tensor image analysis along the perivascular space (DTI-ALPS).

Objective:

We aimed to validate impaired glymphatic flow and explore its association with gray matter volume, cognitive status, and cerebral amyloid deposition on the AD spectrum.

Methods:

80 participants (mean age, 76.9±8.5 years; 57 women) with AD (n = 65) and cognitively normal (CN) (n = 15) who underwent 3T brain MRI including DTI and/or amyloid PET were included. After adjusting for age, sex, apolipoprotein E status, and burden of white matter hyperintensities, the ALPS-index was compared according to the AD spectrum. The association between the ALPS-index and gray matter volume, cognitive status, and quantitative amyloid from PET was assessed.

Results:

The ALPS-index in the AD was significantly lower (mean, 1.476; 95% CI, 1.395-1.556) than in the CN (1.784;1.615-1.952; p = 0.026). Volumes of the entorhinal cortex, hippocampus, temporal pole, and primary motor cortex showed significant associations with the ALPS-index (all, p < 0.05). There was a positive correlation between the ALPS-index and MMSE score (partial r = 0.435; p < 0.001), but there was no significant correlation between the ALPS-index and amyloid SUVRs (all, p > 0.05).

Conclusions:

Decreased glymphatic flow measured by DTI-ALPS in AD may serve as a marker of neurodegeneration correlating with structural atrophy and cognitive decline.

• Authors: Minjae Kim, Yoo Sung Song, Kyunghwa Han, Yun Jung Bae, Ji Won Han, Ki Woong Kim
• Journal: Journal of Alzheimer's disease : JAD (J Alzheimers Dis) Vol. 99 Issue 1 Pg. 279-290 ( 2024) ISSN: 1875-8908 [Electronic] Netherlands
• PMID: 38669532 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Topics

• Humans
• Female
• Male
• Alzheimer Disease (diagnostic imaging, pathology, metabolism)
• Aged
• Cognitive Dysfunction (diagnostic imaging, metabolism, pathology)
• Gray Matter (diagnostic imaging, pathology, metabolism)
• Diffusion Tensor Imaging
• Glymphatic System (diagnostic imaging, pathology, metabolism)
• Positron-Emission Tomography
• Aged, 80 and over
• Brain (diagnostic imaging, pathology, metabolism)