Poster Session 04 Program Schedule
02/15/2024
12:00 pm - 01:15 pm
Room: Majestic Complex (Posters 61-120)
Poster Session 04: Neuroimaging | Neurostimulation/Neuromodulation | Teleneuropsychology/Technology
Final Abstract #92
The subjective as objective: A comparison of extracellular free water content in the white matter of older adults with and without subjective cognitive concerns
Cristina Pinheiro, University of Kentucky, Lexington, United States
Christopher Bauer, University of Kentucky, Lexington, United States
Brian Gold, University of Kentucky, Lexington, United States
Suzanne Segerstrom, Oregon State University, Corvallis, United States
Justin Karr, University of Kentucky, Lexington, United States
Category: Aging
Keyword 1: aging (normal)
Keyword 2: neuroimaging: structural
Keyword 3: executive functions
Objective:
Aging is associated with neuronal damage, which results in increased fluid in the extracellular space. An MRI technique developed through diffusion weighted imaging permits extracellular free water to be measured in vivo. In prior research, extracellular free water content in the white matter of older adults was the strongest predictor of cognitive trajectories compared to three other diffusion weighted imaging metrics and has been associated with reduced performance on executive function tests. Subjective cognitive concerns arise among older adults who may or may not experience deficits on objective neuropsychological tests. Subjective cognitive concerns are clinically important and are associated with a higher risk of progression to mild cognitive impairment or dementia. This study aimed to compare older adults with and without subjective cognitive concerns on extracellular free water content in their white matter and performances on objective neuropsychological tests.
Participants and Methods:
Participants were from an ongoing longitudinal aging study. Participants completed a battery of neuropsychological tests, and a subgroup of these participants subsequently received an MRI of their brain on average 60 days following the neuropsychological test battery. The sample consisted of 80 healthy older adults between the ages of 60 and 95 years old who were further subdivided based on the presence of subjective cognitive concerns, defined as one or more self-reported cognitive concerns on the Medical Outcomes Study Cognitive Functioning Scale. Participants with subjective cognitive concerns (n=41; 74.4 years old, SD=9.2, range: 60-95; 63% female; 95% White; 73.2% college-educated) and without subjective cognitive concerns (n=39; 70.9 years, SD=6.8, range: 62-85, 74% female; 100% White; 82.1% college-educated) completed a neuropsychological test battery consisting of the Rey Auditory Verbal Learning Test, Trail Making Test A and B, Controlled Oral Word Association Test, Digit Span, and Letter-Number Sequencing.
Results:
Participants with and without subjective cognitive concerns were compared on extracellular free water content in white matter and neuropsychological test performance. There was a statistically significant difference in mean extracellular free water content in white matter between older adults with and without subjective cognitive concerns (t=-2.49, p=.015, d=-.56). There was no statistically significant difference between participant’s performance on any of the neuropsychological tests regardless of subjective cognitive concerns (ps>.05, d range: .06-.28).
Conclusions:
There was a main effect of mean extracellular free water content in white matter between participants with and without subjective cognitive concerns. Performance on neuropsychological tests of memory and executive functions did not differ based on the presence of subjective cognitive concerns in this sample. Subjective cognitive concerns are frequently experienced by aging adults and clinically relevant for consideration of a diagnosis of mild cognitive impairment. Underlying neuropathology detected by extracellular free water content in white matter may precede reductions in performance on objective neuropsychological tests.
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