2025 American Academy of Neurology Abstract Website

Emma Peasley¹, Ian Johnson¹, Hailey Brigger¹, Joel Smith¹, Dheeraj Lalwani¹, Julia Zabinska¹, Gordon Sze², Sam Payabvash², Annabel Sorby-Adams³, Jua Iglesias Gonzalez⁴, Matthew Rosen⁴, W. Kimberly³, Adam De Havenon¹, Kevin Sheth¹
¹Neurocritical Care, ²Radiology and Biomedical Imaging, Yale School of Medicine, ³Neurology, ⁴Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School

Objective:

To assess the relationship between hippocampal volume and cognitive ability in patients with cardiovascular risk factors.

Background:

Decreasing hippocampal volume has been associated with cognitive decline in patients with neurodegenerative disease or advanced age. Although cardiovascular risk factors have been associated with increased risk of cognitive impairment, the relationship between hippocampal volume and cognitive ability in patients with these risk factors is underexplored.

Design/Methods:

Patients with at least one cardiovascular risk factor presenting to an emergency department between December 2021 and July 2024 were recruited to receive a fluid-attenuated inversion recovery (FLAIR, Axial 1.6 × 1.6 × 5.8 mm) scan on a 0.064 T MRI (Hyperfine Inc.). A Montreal Cognitive Assessment (MoCA) score was also collected, with a score ≤ 26 out of 30 indicating impairment. A machine learning algorithm (WMH-Synthseg) demonstrating strong agreement between volumes estimated on conventional and LF-MRI in prior research was used for segmentation.

Results:

Scans with associated MoCA scores were available in n=135 patients. Scans with hippocampal volumes ≥ 2 standard deviations (SD) away from the mean (7.23 mL, SD = 1.23 mL) were excluded for a final n=130. The average age was 62.4 (SD = 12.4), and the average MoCA score was 23.0 (SD = 4.4). In a linear regression including age, hippocampal volume, and thalamic volume (to control for generalized atrophy), hippocampal volume was significantly associated with MoCA score (p = 0.016) with a standardized coefficient of 0.255. Age and thalamic volume were not significantly associated with MoCA score (p = 0.118 and p = 0.699, respectively).

Conclusions:

There is a significant, positive relationship between hippocampal volume on LF-MRI and MoCA score in patients with cardiovascular risk factors. Changes in hippocampal volume may mediate cognitive decline due to poor cardiovascular health. Leveraging LF-MRI may allow for the monitoring of these changes in a variety of settings.