Do Patients With Multiple Sclerosis Face Worse COVID-19 Outcomes?

Individuals with multiple sclerosis (MS), compared with the general population, demonstrate worse COVID-19 outcomes, according to study findings published in the journal Multiple Sclerosis and Related Disorders.

Researchers at Isfahan University of Medical Sciences in Isfahan, Iran conducted a retrospective, population-based study from January 1, 2020 to August 22, 2021 to analyze COVID-19 outcomes in individuals with MS compared with the general population.

Approximately 793,301 individuals without MS and 2196 individuals with MS underwent COVID-19 testing at Isfahan University of Medical Sciences. A total of 325,473 people without MS and a total of 829 people with MS tested positive for COVID-19. The researchers included 820 patients with MS who tested positive for COVID-19 and 2494 patients without MS who tested positive as well.

Of the study participants who tested positive for COVID-19, those with MS were younger than their counterparts (mean age, 39.54 vs 45.85; P <.0001) and were also more likely to be women (P <.0001).

During the follow-up period, 133 of the 820 (16.2%) patients with MS who tested positive for COVID-19 required hospitalization, while 412 of the 2494 (16.5%) patients without MS who tested positive for COVID-19 were hospitalized (crude odds ratio [OR], 0.978; 95% CI, 0.79-1.211). After adjusting for age and biological sex, compared with the general population without MS, those with MS demonstrated a 56% increased likelihood of hospitalization due to COVID-19 (adjusted OR [aOR], 1.56; 95% CI, 1.23-1.97).

Younger individuals with MS were more likely to require hospitalization than individuals of the same age without MS (OR, 1.699; 95% CI, 1.289-2.240); however, the researchers did not observe any significant difference in hospitalization between older people with and without MS (OR, 1.005; 95% CI, 0.662-1.524). Hospitalization rates were higher among younger people with relapsing (OR, 1.516; 95% CI, 1.121-2.050) and progressive (OR, 3.678; 95% CI, 1.305-10.366) MS subtypes compared with those without MS, but not in individuals with the clinically isolated syndrome (CIS) MS subtype.

Another factor that seemed to influence COVID-19 outcomes involved the type of MS treatment. People with MS taking rituximab demonstrated higher chances of hospitalization (OR, 5.102; 95% CI, 3.523-7.389).

COVID-19-related mortality was not significantly different between people with MS and the general population (1.3% vs 2%, respectively; crude OR, 0.678; 95% CI, 0.351-1.31). However, following adjustments for age and biological sex, the researchers noted a non-significant increase in the likelihood of mortality among people with MS compared with the general population (aOR, 2.013; 95% CI, 0.95-4.26).

“This study revealed higher odds of hospitalization and mortality due to COVID-19 among PLWMS [people living with MS] in comparison to age- and sex-matched controls from the general population,” the researchers concluded. “Nevertheless, it remains unclear whether the elevated odds are directly associated with MS itself or if they are influenced by factors such as rituximab using, comorbidity, and disease severity.”

Study limitations included the retrospective study design, inability to generalize outcomes outside of the Iranian population, and the potential for changes in patient management over time during the pandemic, which may have influenced patient outcomes.