Multiple Sclerosis Research Repository

“Retinal layer thinning is reflecting disability progression independent of relapse activity in multiple sclerosis”: Gabriel Bsteh

-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).

-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.

-Retinal thinning in absence of optic neuritis is a robust and established marker of MS-associated neuroaxonal damage correlated with disability worsening and faster rates of whole brain, thalamic, and grey matter atrophy, but independent of relapse activity

-PIRA events are reflected by retinal thinning adding an important component of evidence to the concept of PIRA

-the proportion of patients displaying PIRA events in our cohort was 24% over 4 years comprising 59% of all disability worsening events which is well within the range of previously reported rates of PIRA

-a high proportion of disability worsening events occur in the absence of relapses even in RMS patients treated with high efficacious DMT

-PIRA might represent the stratum of MS-associated neurodegeneration that is largely unaffected by DMTs predominantly targeting CNS-inflammation