Is disease-modifying therapy use in multiple sclerosis a risk factor during the COVID-19 pandemic? A large cohort study

Abstract

Objective: This study aims to investigate the relationship between disease-modifying therapies (DMTs) used in people with MS (pwMS) and the risk of COVID-19 in-fection. Methods: This longitudinal cohort study included the MS cohort of 3402 people followed for COVID-19 infection. The whole MS cohort was interviewed at least once for information about COVID-19. A semi-structured interview was developed and performed by a team consisting of a medical doctor, nurse, and physiotherapist. Clinical information was obtained from the patient's medical records. This study was approved by the Noninvasive Research Ethics Board (Date: 08.09.2021, Decision No: 2021/25-06). Results: Of the 487 pwMS infected with COVID-19, 35 reported reinfections. The major differences regarding DMT between pwMS with and without COVID-19 infection were observed for fingolimod, ocrelizumab, and azathioprine. Forty-three (8.9%) people experienced the COVID-19 infection severely or critically; 12 (37.5%) had MS treatment with ocrelizumab. Fifty percent of pwMS who were treated in intensive care (7/14 patients) and died (3/6 patients) were being treated with ocrelizumab. As a result of regression analysis, being younger and using di-methyl fumarate, fingolimod, ocrelizumab, and cladrib-ine DMTs were the main factors associated with having COVID-19 infection group. Conclusions: Current results show that disability due to MS and increased disease duration are not risk factors for COVID-19 infection, while age is negatively associated with contracting COVID-19 infection. These results show no relationship between the MS clinic and COVID-19 in-fection. We have found that using certain DMTs in pwMS increases the risk of contracting COVID-19 infection.