Retinal neuro-axonal loss parallels global disability accrual in progressive multiple sclerosis independently from disease activity

Young Investigator
Simone Guerrieri
San Raffaele Hospital
52
Milan, Italy

Abstract

Background and Aims:
Progressive multiple sclerosis (PMS) is a major challenge in neurology. The visual pathway is now as an elective platform to study demyelination and neurodegeneration in MS. We applied functional (visual evoked potentials-VEPs) and structural (optical coherence tomography-OCT) techniques at this level to assess neural damage in PMS.

Methods:
350 PMS patients (228 SPMS - 122 PPMS) underwent a cross-sectional evaluation comprehensive of EDSS, visual acuity (VA), full-field (ff-VEPs) as well as multifocal (mf-VEPs) VEPs, and OCT. We obtained follow-up data (mean interval 2.0±0.9 years) for 147 patients (52 PPMS and 95 SPMS)
with a parallel collection of clinical records.

Results:
VEPs latency was higher among SPMS compared to PPMS (mean 144.7 vs 137.4 ms, p=0.001 for ff-VEPs, similar results for mf-VEPs). Retinal Nerve Fiber Layer (RNFL) was thinner among SPMS in comparison to PPMS (mean 79.9 vs 88.5 μm, p<0.001), with similar results for Ganglion Cell-Inner
Plexiform Layer (GCIPL), independently from previous optic neuritis (ON). Reclassifying our cohort according to EDSS status (“stability” n.70 vs “worsening” n.53) we found a difference in terms of RNFL evolution (mean annualized percent change -0.2 vs -0.9 %/year respectively, p=0.010), independently from MRI activity, with a correlation between EDSS and RNFL change (ρ=-0.359, p=0.003).

Conclusions:
Our results suggest a greater functional-structural involvement of the visual system in SPMS compared to PPMS, independently from previous ON. The longitudinal relation between RNFL thinning and EDSS worsening suggests OCT to represent a useful tool to assess disease progression and neuroprotection in PMS.

Disclosures:
Part of this work was supported by Merck, Geneva, Switzerland. Merck is the biopharmaceutical division of Merck KGaA, Darmstadt, Germany.

Retinal neuro-axonal loss parallels global disability accrual in progressive multiple sclerosis independently from disease activity.

Simone Guerrieri1, Marco Pisa1, Roberta Reniè2, Roberto Santangelo1, Silvia Girola1, Huang Su-Chun1, Lucia Moiola1, Vittorio Martinelli1, Massimo Filippi1, Giancarlo Comi1, Letizia Leocani1.
1 Department of Neurology, San Raffaele Hospital, Vita-Salute San Raffaele University, Milan, Italy
2 Department of Neurosciences, Mental Health and Sensory Organs, Faculty of Medicine and Psychology, Centre for Experimental Neurological Therapies (CENTERS), Sapienza University, Rome, Italy