1Nahad Sedaghat, 1Masoud Etemadifar, 1Hosein Nouri, 1Amir Parsa Abhari, 1Shiva Maleki, 1Alireza Amin, 2Mehri Salari

1Isfahan University of Medical Sciences, Isfahan, Iran; 2Shahid Beheshti University of Medical Sciences, Tehran, Iran


Neurological complications of COVID-19 have raised serious concerns among the experts, and hence, many mechanisms have been proposed to explain it. We sought to collect evidence by investigating the possible effect of the virus on multiple sclerosis (MS) disease course, in COVID-19-contracted people with relapsing-remitting multiple sclerosis (RRMS).

Material(s) and Method(s):

This prospective-retrospective hybrid cohort study conducted from July 2020 until July 2021, compares the rates of probable disease progressions (PDP) and relapses between the pre- and post-COVID-19 periods of RRMS patients, using non-parametric tests, a matched binary logistic model offset by follow-up, Kaplan-Meier plots, and a cox regression model.


The PDP rate (0.06 vs 0.19, P = 0.04) and relapse rate (0.21 vs 0.30, P = 0.30) were both lower in the post-COVID-19 period compared to the pre-COVID-19 period. However, matched binary logistic model offset by follow-up failed to display a significant difference in odds of PDP (OR [95% confidence interval]: 0.41 [0.13, 1.34], P = 0.14) and relapse (OR [95% confidence interval]: 0.99 [0.45, 2.17], P = 0.99), at the endpoints of pre- and post-COVID-19 periods. Kaplan-Meier plots and cox regression model did not show significant difference between the pre- and post-COVID-19 periods, regarding both the PDP rates (HR [95% CI]: 0.46 [0.12, 1.73], P = 0.25) and relapse rates (HR [95% CI]: 0.69 [0.31, 1.53], P = 0.36).


Our results suggest that COVID-19 contraction is unlikely to increase the risk of MS progression and relapse in the following months after infection.