Table 1_FreeSurfer-based amygdala subfield volumetry in long COVID and ME/CFS: clinical and immunological correlations.xlsx

In long COVID, G-protein-coupled receptor (GPCR) autoantibodies were nominally negatively associated with right medial nucleus volume. In ME/CFS, performance status was nominally positively associated with the right basal nucleus, right paralaminar nucleus, and right whole amygdala, and plasmablasts were nominally positively associated with the right corticoamygdaloid transition area. No group difference or partial correlation remained significant after correction for multiple testing.</p>Conclusion<p>Although no finding survived correction for multiple testing, the exploratory results suggest that amygdala-related structural variation may be relevant to both long COVID and ME/CFS.

The nominal, uncorrected within-group patterns centered on olfactory-related amygdala nuclei and GPCR autoantibodies in long COVID, and on amygdala structure, functional severity, and plasmablasts in ME/CFS; however, these patterns do not support a conclusion of between-group differences. These observations are hypothesis-generating and do not establish disease-specific mechanisms. Prespecified validation in larger longitudinal and independent cohorts is required.</p>