No correlation was seen between disease-modifying therapy (DMT) exposure and COVID-19 severity in multiple sclerosis (MS) patients, registry data in France showed.
High scores on the Expanded Disability Severity Scale (), age, and obesity, however, were tied to increased risk for severe COVID-19 in the registry, reported Celine Louapre, MD, of Sorbonne Universite in Paris, and co-authors in .
Of 347 MS patients with an average age of about 45 and a confirmed or highly suspected COVID-19 diagnosis, 73 (21%) were hospitalized and 12 (3.5%) died.
"The main risk factor for severe COVID-19 in patients with MS was neurological disability measured by the EDSS score, followed by age and obesity -- these two risk factors being already identified in the general population," Louapre said. "Conversely, MS disease-modifying therapies were not associated with an increased risk of severe COVID-19."
Most patients who died of COVID-19 were untreated and had high EDSS scores, Louapre told Ƶ. "The overall death rate in the registry was 3.5%, which seems slightly higher than the expected death rate in this rather young population," she added.
The findings echo what MS specialists have reported so far in North America, said Robert Fox, MD, of the Cleveland Clinic in Ohio, who wasn't involved with the study.
Three questions are important to MS patients, Fox told Ƶ: "Do people with MS get worse COVID than people in the background population? What are the risk factors for doing worse? And the big, big question -- do the MS therapies make it worse?"
Overall, it appears that COVID-19 affects MS patients in ways that mirror the general population and, importantly, that "patients on MS therapies do not seem to fare worse," he said.
Similar to the French registry, the database -- a joint effort of the National MS Society, Consortium of MS Centers, and the Multiple Sclerosis Society of Canada -- suggests that MS patients on treatment have better outcomes than those who are untreated, he added.
In the multicenter Covisep study, Louapre and co-authors looked at 347 MS patients with a mean disease duration of 13.5 years. Most patients (79.5%) had relapsing-remitting MS, and 72% were women. Median EDSS was 2.0, suggesting minimal MS disability, though EDSS scores ranged from 0 (no disability) to 9.5 (totally helpless bed patients). The majority of patients (81.8%) in the registry were receiving DMTs.
The main outcome was COVID-19 severity, assessed on a 7-point scale that ranged from 1 (not hospitalized with no limitations on activities) to 7 (death), with a cutoff at 3 (hospitalized and not requiring supplemental oxygen).
Seventy-three patients (21.0%) had a COVID-19 severity score of 3 or higher. The proportion of patients with a severity score of 3 or more was higher among those not receiving DMTs compared with those receiving DMTs (46.0% vs 15.5%; P<0.001). Fever and dyspnea were more common in MS patients hospitalized with COVID-19; anosmia, ageusia, and headache were more common in patients not hospitalized.
Independent risk factors for a COVID-19 severity score of 3 or more were age (OR per 10 years 1.9, 95% CI 1.4-2.5), EDSS score of 6 or higher (OR 6.3, 95% CI 2.8-14.4), and obesity (OR 3.0, 95% CI 1.0-8.7). EDSS score was associated with the highest variability of COVID-19 severe outcome (R2 0.2), followed by age (R2 0.06) and obesity (R2 0.01).
"Our data do not support an increased risk of severe outcome associated with DMTs, which should reinforce the recommendation of not stopping current DMTs and not delaying treatment initiation in patients who have higher disease inflammatory activity, risk for relapses, or subsequent disability," the researchers wrote.
"At the start of the COVID-19 epidemic, patients and neurologists had many questions about the risk of this infection in patients with MS, most of whom receive immunomodulatory or immunosuppressive therapy," Louapre noted. This analysis provides real-life data to identify these risk factors, she said.
Study limitations include potential referral bias. In addition, DMTs are prescribed more frequently in patients who are younger, who have a relapsing form of MS, and who have a lower level of disability.
Disclosures
This study did not receive specific funding.
The authors reported relationships with Biogen, Novartis, Roche, Sanofi, Teva, Merck Serono, Bayer Schering Pharma, Alexion Pharmaceuticals, MedDay, Genzyme, GeNeuro, Octapharma, AbbVie, Celgene, and Janssen.
Primary Source
JAMA Neurology
Louapre C, et al "Clinical characteristics and outcomes in patients with coronavirus disease 2019 and multiple sclerosis" JAMA Neurol 2020; DOI: 10.1001/jamaneurol.2020.2581.