Longitudinal Assessment of the Relationship Between Visual Evoked Potentials and Cognitive Performance in Multiple Sclerosis.

Objective: Visual evoked potentials (VEPs) can provide insight into disease activity in people with multi-ple sclerosis (PwMS). However, few studies have tracked concurrent changes in VEPs and cognitive func-tioning over time in MS. To address this, we examined the longitudinal relationship between VEP and cognitive performance in PwMS over a two-year period. Methods: At baseline (T1) and follow-up (T2, 2.14 years after baseline, on average), P100 peak latency and inter-ocular latency (IOL) between eyes were calculated from the VEP elicited for checkerboard pattern-reversal stimuli. Cognitive performance was assessed for seven different domains (NeuroTrax battery). The potential for VEP variables to predict the T1-to-T2 change in cognitive performance was assessed in a series of multiple linear regression models. Results: Baseline IOL and VEP latency were significantly associated with T1-to-T2 change in information processing speed. Post-hoc analyses indicated that PwMS that had both prolonged VEP latency and ele-vated IOL at baseline tended to exhibit greater information processing speed decline. Increase in VEP latency from T1-to-T2 was also associated with decline in psychomotor function over time. Conclusions: These findings provide evidence that VEP measures can serve as valuable prognostic indica-tors of longitudinal cognitive change in PwMS. Significance: Visual system neurophysiology corresponds with changes in speeded cognitive performance in MS. (c) 2022 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.