Synthetic MRI Neuroimaging Correlates of Frailty: Correlations Between Frailty Scales and Brain Structural Integrity

Frailty, a common condition in the elderly, is characterized by a decline in physiological reserves and an increased vulnerability to stressors, leading to negative health outcomes such as falls, fractures, and prolonged recovery from illness. Despite its clinical significance, the relationship between frailty and cerebral health, particularly the correlation of frailty evaluation scales with brain structural integrity changes, is not well-defined. The study aims to investigate the associations between frailty and brain structure, focusing on the relationship between various frailty scales and brain volumetric and relaxometric changes as identified by synthetic MRI neuroimaging techniques.

This prospective study initially enrolled 109 participants from the neurology ward. After applying exclusion criteria, 41 participants were included in the final analysis. Data on demographics, medical history, and physical examinations were collected. Synthetic MRI was conducted using a MAGnetic resonance image Compilation (MAGiC) with images processed using SyMRI 8.0 and SPM12 software for volumetric and relaxometric analyses. Frailty was assessed using the Clinical Frailty Scale (CFS), Fried scale, FRAIL scale, and Edmonton Frailty Scale (EFS). Statistical analysis was performed by partial correlation analysis, adjusting for age, gender, and history of stroke, to examine the relationships between global and regional brain volumetric and relaxometry parameters with frailty scales. To control for multiple comparisons, the false discovery rate (FDR) method was applied, with statistical significance set at FDR-adjusted p value < 0.05.

Compared to non-frail participants, frail individuals exhibited significantly lower gray matter volumes in the cerebellum, hippocampus, and thalamus, as well as reduced white matter volumes globally and in the temporal and parietal lobes. Brain relaxometry revealed higher hippocampal and thalamic T1 and T2 values in the frail group. The CFS and EFS were significantly correlated with global and regional gray and white matter volumes, indicating a link between frailty severity and brain structural integrity.

This study highlights significant correlations between frailty scales, particularly CFS and EFS, and changes in brain volumetry and relaxometry in specific brain regions. These findings suggest that the CFS and EFS may serve as sensitive frailty scales for assessing the impact of frailty on brain structure. Synthetic MRI holds promise as a valuable neuroimaging tool for diagnosing and evaluating frailty. Further research is needed to confirm these findings and enhance clinical strategies for frailty assessment and intervention.