Black race, certain MS treatments may also be factors

Multiple sclerosis (MS) disability and older age were among risk factors for a more severe clinical course of Covid-19 in MS patients infected with SARS-CoV-2, the cross-sectional North American COViMS registry showed.

Black race and rituximab treatment (off-label for MS in the U.S.) were also associated with more severe Covid-19 in MS patients, reported Amber Salter, PhD, of Washington University in St. Louis, and co-authors in JAMA Neurology.

“Knowledge of these risk factors may improve the treatment of patients with MS and Covid-19 by helping clinicians identify patients requiring more intense monitoring or Covid-19 treatment,” Salter and colleagues wrote.

The COViMS registry was started in April 2020 in response to the pandemic and includes information reported by health care professionals. The analysis included data through December 2020 on 1,626 patients with MS who were infected with SARS-CoV-2. Most (97%) lived in the United States, and infection was laboratory-confirmed in about 82% overall.

Salter and colleagues rated Covid-19 severity as four levels: not hospitalized, hospitalization only, admission to the intensive care unit and/or required ventilator support, and death. For age, disability, and MS medication, they found:

  • Each 10-year increase in age was associated with an increased risk of hospitalization and death (hospitalization OR 1.3, 95% CI 1.1-1.6; death OR 1.8, 95% CI 1.2-2.6).
  • Being non-ambulatory was associated with 2.8-fold increased odds of hospitalization, a 3.5-fold increase for ICU admission and/or ventilation, and a 25-fold increased risk of death in adjusted analysis compared with fully ambulatory patients (hospitalization OR 2.8, 95% CI 1.6-4.8; intensive care unit/ ventilator support OR 3.5, 95% CI 1.6-7.8; death OR 25.4, 95% CI 9.3-69.1).
  • Compared with MS patients not taking any disease modifying therapy (DMT), those taking rituximab had 4.5-fold increased odds of hospitalization for Covid-19. Ocrelizumab also increased the odds of hospitalization (OR 1.63). Glucocorticoid use in the prior 2 months increased risk of hospitalization by about 2-fold and of death, by 4-fold.

Registry studies in other parts of the world have described regional experiences with MS and Covid-19. A French study found of 347 patients with MS, mortality rate was 3.5% for Covid-19 infection, while infection severity was higher for those not treated with any DMT. More severe infection was associated with advancing age (OR 1.9 per each 10 years), disability score, and obesity. An Italian study reported on 565 suspected and 279 confirmed Covid-19 cases in MS patients, and found recent therapy with methylprednisolone and use of an anti-CD20 agent (rituximab or ocrelizumab) were associated with more severe infection.

“The Italian MS and Covid-19 registry did not distinguish between anti-CD20 therapies but showed worse clinical outcomes and higher risk with longer duration of anti-CD20 exposure,” Salter and co-authors wrote. The sample size in the French study may have limited the ability to detect associations, they noted.

“Taken together, these studies suggest increased risks of Covid-19 in people treated with rituximab,” the researchers observed. “Differences in associations with Covid-19 outcomes for the two anti-CD20 monoclonal antibody therapies (rituximab and ocrelizumab) could be due to longer treatment duration with rituximab because ocrelizumab was more recently available.”

The COViMS cohort was 74% female and had mean age of 48 with average disease duration of 13 years. Most participants where white (62%); 21% were Black, and about 12% were Hispanic/Latinx. Relapsing-remitting disease was the most frequent type of MS (80.4%).

Overall, about 31% were taking ocrelizumab, 5% rituximab, and 15% were on no MS treatment. Most patients could walk (75%), while about 15% required assistance to walk and 9.5% were non-ambulatory.

By severity category, 19.7% were hospitalized, 6.4% admitted to the ICU, 3.8% required mechanical ventilation, and 3.3% died, with mortality rates ranging from 1.2% (age 35-44) to 22.6% (age 75 and older). There were 54 deaths in total.

“Higher proportions of younger-aged Black patients with MS had worse outcomes vs younger White patients,” Salter and co-authors wrote. “Clinical severity in 190 Hispanic/Latinx patients with MS was generally similar to those of White patients with MS across age levels.”

Most Covid-19 symptoms lasted 2 weeks or longer in this study, with about 52% reporting symptoms for 14 or more days and about 21% reporting symptoms for less than 1 week.

“No clear association of MS diagnosis with risk of developing Covid-19 could be established in this study because of the unknown numbers at risk in the MS populations from whom cases were reported,” Salter and colleagues wrote. “However, ambulatory disability from MS was strongly associated with worse Covid-19 outcomes, consistent with other studies.”

Limitations include data based on voluntary reporting by health care professionals, with possible bias to report more severe cases. Also, much of the registry data, including 21 of 54 deaths, is from the Northeast U.S., which may limit generalizability.

“The COViMS Registry is ongoing, and regional shifts are expected as the pandemic expands within North America,” the researchers noted. “Some patients may have behaved more cautiously and adhered more strictly to public health recommendations because of MS, but this was not captured.”

  1. Multiple sclerosis (MS) disability and older age were among risk factors for a more severe clinical course of Covid-19 in MS patients infected with SARS-CoV-2, the cross-sectional North American COViMS registry showed.
  2. Black race and rituximab treatment (off-label for MS in the U.S.) were also associated with more severe Covid-19 in MS patients.

Paul Smyth, MD, Contributing Writer, BreakingMED™

Support for the Covid-19 Infections in MS Registry is provided by the National Multiple Sclerosis Society, the Consortium of Multiple Sclerosis Centers, and the MS Society of Canada.

Salter reports grants from National Multiple Sclerosis Society and was a statistical editor for Circulation: Cardiovascular Imaging during the conduct of the study.

 

Cat ID: 130

Topic ID: 82,130,730,933,190,926,130,36,192,927,925,934

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