Retinal layer thinning is reflecting disability progression independent of relapse activity in multiple sclerosis.

BACKGROUND

PIRA (progression independent of relapse) has emerged as a term to quantify the proportion of disability worsening due to non-inflammatory neurodegenerative processes in multiple sclerosis (MS).

OBJECTIVE

To determine the impact of PIRA on retinal thinning, a biomarker of neuroaxonal degeneration in MS, in comparison to traditional disability worsening and relapse.

METHODS

In a 4-year, prospective observational study including 171 relapsing MS (RMS) patients, retinal thinning was determined by annual spectral-domain optical coherence tomography measuring macular ganglion-cell-and-inner-plexiform-layer (GCIPL) and peripapillary-retinal-nerve-fibre-layer (pRNFL). PIRA was defined as an expanded disability status scale (EDSS) or symbol digit modalities test (SDMT) worsening confirmed after 24 weeks with no relapse in the 30 days before or after the disability worsening.

RESULTS

Each PIRA event was associated with a mean additional loss of GCIPL (1.8 µm) and pRNFL (1.9 µm), similar to the impact of EDSS and SDMT worsening. Overall relapse and relapse without subsequent EDSS worsening did not influence retinal thinning, while a relapse with EDSS worsening was associated with an additional loss of GCIPL (1.3 µm) and pRNFL (1.4 µm).

CONCLUSIONS

PIRA is associated with retinal thinning, likely reflecting neurodegenerative processes, not directly associated with focal inflammation. It might be a clinical measure to identify MS patients with ongoing MS-associated neurodegeneration.

Informations de copyright

© The Author(s) 2020.

Déclaration de conflit d'intérêts

Conflict of Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Gabriel Bsteh: has participated in meetings sponsored by, received speaker honoraria or travel funding from Biogen, Celgene, Merck, Novartis, Sanofi-Genzyme and Teva, and received honoraria for consulting Biogen, Roche and Teva. Harald Hegen: has participated in meetings sponsored by, received speaker honoraria or travel funding from Bayer, Biogen, Merck, Novartis, Sanofi-Genzyme, Siemens and Teva, and received honoraria for consulting Biogen and Teva. Patrick Altmann: has participated in meetings sponsored by, received speaker honoraria or travel funding from Biogen, Merck, Roche, Sanofi-Genzyme and Teva, and received honoraria for consulting from Biogen. He received a research grant from Quanterix International and was awarded a combined sponsorship from Biogen, Merck, Sanofi-Genzyme, Roche, and Teva for a clinical study. Michael Auer: received speaker honoraria and/or travel grants from Biogen, Merck, Novartis and Sanofi Genzyme. Klaus Berek: has participated in meetings sponsored by and received travel funding from Roche. Franziska Di Pauli has participated in meetings sponsored by, received honoraria (lectures, advisory boards, consultations) or travel funding from Bayer, Biogen, Merck, Novartis, Sanofi-Genzyme, Teva, Celgene and Roche. Sebastian Wurth: has participated in meetings sponsored by, received honoraria or travel funding from Allergan, Biogen, Ipsen Pharma, Merck, Novartis, Roche, Sanofi Genzyme and Teva. Anne Zinganell: has participated in meetings sponsored by, received speaking honoraria or travel funding from Biogen, Merck, Sanofi-Genzyme and Teva. Paulus Rommer: has received honoraria for consultancy/speaking from AbbVie, Allmiral, Alexion, Biogen, Merck, Novartis, Roche, Sandoz, Sanofi Genzyme, has received research grants from Amicus, Biogen, Merck, Roche. Florian Deisenhammer: has participated in meetings sponsored by or received honoraria for acting as an advisor/speaker for Alexion, Almirall, Biogen, Celgene, Merck, Novartis, Roche and Sanofi-Genzyme. His institution received scientific grants from Biogen and Sanofi-Genzyme. Fritz Leutmezer: has participated in meetings sponsored by or received honoraria for acting as an advisor/speaker for Bayer, Biogen, Celgene, MedDay, Merck, Novartis, Roche, Teva and Sanofi-Genzyme. Thomas Berger: has participated in meetings sponsored by and received honoraria (lectures, advisory boards, consultations) from pharmaceutical companies marketing treatments for MS: Allergan, Bayer, Biogen, Bionorica, Celgene, MedDay, Merck, Novartis, Octapharma, Roche, Sanofi-Genzyme, Teva. His institution has received financial support in the past 12 months by unrestricted research grants (Biogen, Bayer, Merck, Novartis, Sanofi Aventis, Teva and for participation in clinical trials in multiple sclerosis sponsored by Alexion, Bayer, Biogen, Merck, Novartis, Octapharma, Roche, Sanofi-Genzyme, Teva.