In an observational French cohort study, Expanded Disability Status Scale (EDSS) and age were found to be independent risk factors of severe COVID-19, while exposure to immunomodulating disease-modifying treatment (DMT; interferon and glatiramer acetate) were independently associated with lower COVID-19 severity [1]. There was no association between immunosuppressive therapies and COVID-19 severity.

The main objectives of this multicenter, retrospective study were to determine the severity of COVID-19 in MS patients, and the risk factors in MS patients for developing a severe form of COVID-19. The results were presented as a late-breaking abstract by Dr Celine Louapre (Pitié-Salpêtrière Hospital, France). The study cohort (COVISEP registry) that was analyzed included 405 MS patients with confirmed or highly suspected COVID-19 infection between 1 March 2020 and 14 July 2020.

Mean age was 44.7 years, 293 (72%) were female, and mean MS duration was 13.4 years. Median EDSS was 2.0 (range: 0–9.5); 326 patients (80.5%) used a DMT. COVID-19 severity was assessed on a 7-point ordinal scale, ranging from 1 (not hospitalized, no limitations on activities) to 7 (death). Cut-off score was at 3 (hospitalized, not requiring supplemental oxygen). Of 405 participants, 78 (19.3%) had a COVID-19 severity score ≥3; 12 patients (3.0%) died from COVID-19. Dr Louapre noted that most of the very severe COVID-19 patients did not use any DMT. The percentage of patients with a COVID-19 severity score ≥3 in patients with and without a DMT was 14.4% versus 39.2% (P<0.001).

Multivariate analysis showed that independent risk factors for COVID-19 severity score ≥3 were higher age (OR for 10 years 1.8; 95% CI 1.4–2.4) and higher EDSS (OR for EDSS ≥6 4.5; 95% CI 2.0-10.0). Obesity and cardiac comorbidity were also associated with severe COVID-19 (OR 2.58; 95 CI 0.96-6.91; and OR 2.39; 95% CI 0.93-6.17, respectively). Immunomodulatory treatment (interferon or glatiramer acetate) was associated with lower risk of COVID-19 severity score ≥3 (OR 0.2; 95% CI 0.05–0.83) compared with no treatment. Dr Louapre concluded that knowing these risk factors should help to guide an individualized clinical management of MS patients during the COVID-19 pandemic.


  1. Louapre C. MSVIRTUAL2020, Abstract SS02.06