Risk of Getting COVID-19 in People With Multiple Sclerosis
A Case-Control Study
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Abstract
Background and Objectives Several studies have assessed risk factors associated with the severity of COVID-19 outcomes in people with multiple sclerosis (PwMS). The potential role of disease-modifying therapies (DMTs) and demographic and clinical factors on the risk of acquiring SARS-CoV-2 infection has not been evaluated so far. The objective of this study was to assess risk factors of contracting SARS-CoV-2 infection in PwMS by using data collected in the Italian MS Register (IMSR).
Methods A case-control (1:2) study was set up. Cases included PwMS with a confirmed diagnosis of COVID-19, and controls included PwMS without a confirmed diagnosis of COVID-19. Both groups were propensity score–matched by the date of COVID-19 diagnosis, the date of last visit, and the region of residence. No healthy controls were included in this study. COVID-19 risk was estimated by multivariable logistic regression models including demographic and clinical covariates. The impact of DMTs was assessed in 3 independent logistic regression models including one of the following covariates: last administered DMT, previous DMT sequences, or the place where the last treatment was administered.
Results A total of 779 PwMS with confirmed COVID-19 (cases) were matched to 1,558 PwMS without COVID-19 (controls). In all 3 models, comorbidities, female sex, and a younger age were significantly associated (p < 0.02) with a higher risk of contracting COVID-19. Patients receiving natalizumab as last DMT (OR [95% CI]: 2.38 [1.66–3.42], p < 0.0001) and those who underwent an escalation treatment strategy (1.57 [1.16–2.13], p = 0.003) were at significantly higher COVID-19 risk. Moreover, PwMS receiving their last DMT requiring hospital access (1.65 [1.34–2.04], p < 0.0001) showed a significant higher risk than those taking self-administered DMTs at home.
Discussion This case-control study embedded in the IMSR showed that PwMS at higher COVID-19 risk are younger, more frequently female individuals, and with comorbidities. Long-lasting escalation approach and last therapies that expose patients to the hospital environment seem to significantly increase the risk of SARS-CoV2 infection in PwMS.
Classification of Evidence This study provides Class III evidence that among patients with MS, younger age, being female individuals, having more comorbidities, receiving natalizumab, undergoing an escalating treatment strategy, or receiving treatment at a hospital were associated with being infected with COVID-19. Among patients with MS who were infected with COVID-19, a severe course was associated with increasing age and having a progressive form of MS, whereas not being on treatment or receiving an interferon beta agent was protective.
Glossary
- DMT=
- disease-modifying therapy;
- EC=
- ethical committee;
- EDSS=
- Expanded Disability Status Scale;
- IMSR=
- Italian MS Register;
- IQR=
- interquartile range;
- MedDRA=
- Medical Dictionary for Regulatory Activities;
- MoA=
- mechanisms of action;
- MS=
- multiple sclerosis;
- PS=
- propensity score;
- PwMS=
- people with multiple sclerosis
Footnotes
Go to Neurology.org/NN for full disclosures. Funding information is provided at the end of the article.
Italian MS Register coinvestigators are listed in Appendix 2.
The Article Processing Charge was funded by the authors.
Class of Evidence: NPub.org/coe
COVID-19 Resources: NPub.org/COVID19
- Received August 12, 2021.
- Accepted in final form December 15, 2021.
- Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.
This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND), which permits downloading and sharing the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.
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