Purpose: We sought to determine if structural network parameters add to traditional markers of MS treatment response following immunoablation and autologous haemopoietic stem cell transplantation (IAHSCT). The post-IAHSCT paradigm afforded us the opportunity to study MS patients after relapsing biology had been effectively suppressed, enabling us to study the cortical substrate of progressive MS in a less confounded manner.
Methods: In this analysis of data from a phase 2 prospective study, associations between magnetic resonance graph parameters, N-acetylaspartate to creatine ratio (NAA/Cr), and serum neurofilament light chain (sNfL), amongst other markers, were assessed at 3 months pre-and 12 months post-IAHSCT. Correlations between graph parameter score changes and markers of brain health were calculated. Predictive factors of NAA/Cr or sNfL levels were calculated, adjusting for reference models. Model improvements were evaluated using the G2 likelihood-ratio test.
Results: 24 patients (aged 18-38) were evaluated. Post-IAHSCT, high NAA/Cr and low sNfL (both measures of neuronal injury) were respectively associated with more favourable degree, density, clustering and path lengths, and degree, γ, and path length. Post-IAHSCT, absolute change in degree, path length and γ were associated with NAA/Cr and sNfL. Multivariate analysis demonstrated that the relative change in network parameters after IAHSCT accounted for 14% and 35% more variance in NAA/Cr and sNfL levels respectively than the reference model alone.
Conclusions: Cross-sectionally and longitudinally, network parameters demonstrate added utility as markers of disease severity in MS. These measures have the potential to capture cortical changes relevant to progressive non-relapsing biology in MS.
Keywords: Graph parameters; Multiple sclerosis; Network connectivity; Serum neurofilament; Stem cell transplantation; Structural magnetic resonance.
Copyright © 2023. Published by Elsevier B.V.