COVID-19 Vaccination Does Not Increase Relapse Risk in Patients With Multiple Sclerosis

COVID-19 vaccination does not increase the risk of severe relapse for most patients with multiple sclerosis (MS), according to study results published in the American Journal of Neurology.

“People with MS have an increased risk of severe COVID infection due to their level of motor disability or exposure to treatments that suppress their immune systems,” said Xavier Moisset, MD, PhD, of Clermont Auvergne University in Clermont-Ferrand, France. “Some previous studies have found relapses following vaccination, leading some people to not seek the recommended booster doses,” he added.

The study involved 124 545 people with MS in France who had been living with MS for an average of 14 years. Dr Moisset and his team followed the participants for 45 days after vaccination, focusing on relapses that required treatment with high-dose corticosteroids. Of the study participants, 82% received at least one dose of a COVID-19 vaccine by December 31, 2021, 95% received a second dose, and 59% received a booster.

After adjusting for factors that could affect relapse likelihood, such as time of year and disease-modifying therapy, no increased risk of severe relapse following COVID-19 vaccination was found in the general MS population, with a combined incidence rate ratio (IRR) of 0.97. This held across multiple vaccine types, including Pfizer BioNTech, Moderna, AstraZeneca, and Janssen.

The findings are particularly reassuring for patients MS patients, who face an increased risk of severe COVID-19 infection due to motor disabilities or immunosuppressive treatments. However, the study did identify a small increase in relapse risk after the third booster dose for a specific subgroup, which included patients with high MS activity who were not taking MS medications. Dr Moisset advised that these patients should receive disease-modifying treatment before booster vaccination.

“Our findings are reassuring that these vaccines can be used without any worry about the risk of relapse,” said Dr Moisset. “The absence of such a risk is encouraging for people with MS that they may receive booster shots when needed, especially if booster shots are to be repeated in the future,” he continued.

References

Moisset X, Leray E, Chenaf C, et al. Risk of relapse after COVID-19 vaccination among patients with multiple sclerosis in France: a self-controlled case series. Neurology. 2024;103(5):e209662. doi:10.1212/WNL.0000000000209662

EurekAlert!. Good news for people with MS–COVID-19 vaccine not tied to relapse. Published online August 14, 2024. Accessed September 11, 2024. https://www.eurekalert.org/news-releases/1054107