Vaccinations Not Associated with Multiple Sclerosis Flare-ups According to New Study

According to results from a nationwide French study published in JAMA Neurology, there was no association between vaccinations and incidence of severe multiple sclerosis (MS) flare-ups requiring hospitalization. The findings were consistent regardless of age range, whether the participants were male or female, and for 3 commonly administered vaccinations assessed in the study, including the influenza vaccine, the pneumococcal vaccine, and a combination diphtheria, tetanus, poliomyelitis, pertussis, and Hemophilus influenzae (DTTPHi) vaccine used in France.

The study analyzed data from a cohort of 106,523 people from the System of National Health Databases in France who were diagnosed with MS between 2007 and 2017. Of this cohort, 35,256 people had severe MS flare-up that required hospitalization, with a total of 54,036 hospitalizations altogether. Researchers observed vaccine exposure during follow-up, defined as receipt of either the combination DTTPHi vaccine, the pneumococcal vaccine, or the influenza vaccine, and then conducted conditional logistic regression to identify statistical associations with hospitalizations associated with severe MS flare-ups. Vaccinations were included in the statistical analysis if they occurred in the 60 days prior to hospitalization.

The analysis revealed the following adjusted odds ratios (AOR) for hospitalization for MS flare-up and prior vaccination:

• 1.0 (95% CI, .92-9) for all vaccines
• .95 (95% CI, .82-1.11) for the DTPPHi vaccine
• 1.20 (95 CI%, 0.94-1.55) for the pneumococcal vaccine
• .98 (95% CI, .94-1.55) for the influenza vaccine

These data suggest that there are no statistical associations between vaccine exposure and severe MS flare-up requiring hospitalization. These findings are significant, although the study authors note that additional research is needed to further characterize the relationship between other types of vaccines, including for COVID-19, and MS flare-ups.