COVID-19 infection in MS patients and risk of following clinical/MRI disease activity: a propensity score matching study

ABSTRACT

Introduction: Several studies in literature suggest that viral infections may trigger multiple sclerosis (MS) relapses. Among these, respiratory tract infections seem to be the most frequent. To date, there are very few data about the association between COVID-19 infection and the risk of relapses in MS. Objective(s) To evaluate the risk of clinical/MRI disease activity after COVID-19 infection in patients with MS. Method(s) We prospectively collected all incident cases of COVID-19 in a population of approximately 1500 MS patients followed by the MS Center of the AOU Citta della Salute e della Scienza di Torino University Hospital, from March 2020 onwards. Clinical features and outcome of the COVID-19 infection, and MS clinical/MRI outcomes in the 6 months following COVID-19 infection were recorded. Propensity score matching was used to compare MS clinical/MRI outcomes over 6 months between patients with or without COVID-19 infection, matched for age, sex, disease duration and MS disease-modifying treatment. Result(s) 143 patients with COVID-19 infection were identified 103 F, 40 M, with median age of 46 (range 18-82 years). 132/143 had a relapsing-remitting form of MS, while 11 had a progressive form (primary/secondary). 127/143 subjects were under DMT at the time of the infection. 68/143 patients had already received at least one vaccine dose at the time they contracted the infection. Outcome of COVID-19 was usually favorable with mild disease not requiring hospitalization;severe disease was observed in 14 patients, two of whom died. Symptoms suggestive of long COVID (defined as persistence of symptoms after 4 weeks from the resolution of the infection) were observed in 43 patients (30%). In multivariate forward logistic regression, the only variable predictive of long COVID was anti-CD20 therapy (OR 2.42, p = 0.027). No significant differences were found in MS clinical/MRI outcomes (NEDA-3 at 3 and 6 months) after COVID-19 infection, compared to matched MS patients without COVID-19 infection (NEDA-3 at 3 months 78.3% vs 84.8%, p = n.s.;NEDA-3 at 6 months 66.2% vs 76.1%, p = n.s.). Conclusion(s) COVID-19 infection does not appear to influence the risk of MS clinical/MRI disease activity in the months following the infection. Persistence of symptoms suggestive of long Covid is quite common in MS patients.