No Association Between SARS-CoV-2 Vaccines and New-Onset Seizures, finds Comprehensive Review

"In the pooled analyses of more than 118,000 participants in randomized clinical trials (RCTs), the incidence proportion of new-onset seizures after SARS-CoV-2 vaccination was not statistically different between vaccine recipients and placebo recipients or unvaccinated participants," the researchers reported in JAMA Neurology.

Seizures are an adverse effect of the SARS-CoV-2 vaccine. However, no study has answered whether there is any association between seizures in the general population and COVID-19 vaccination. Considering this, Ali Rafati, School of Medicine, Iran University of Medical Sciences, Tehran, Iran, and colleagues aimed to evaluate the seizure incidence among SARS-CoV-2 vaccine recipients compared with those who received a placebo.

For this purpose, the researchers systematically searched online databases and the references of the included studies from 2019 to 2023. RCTs reporting seizure incidence with SARS-CoV-2 vaccination were included.

The study is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework, and the Mantel-Haenszel method was used. The risk of bias in the studies was evaluated using the Cochrane assessment tool for RCTs.

The outcome of interest was new-onset seizure incidence proportion compared among (1) SARS-CoV-2 vaccine recipients and (2) placebo recipients. The study included six RCTs.

The study led to the following findings:

• Results of the pooled analysis comparing the incidence of new-onset seizure between the 63 521 vaccine and 54 919 placebo recipients in the 28-day follow-up after vaccine/placebo injection showed no statistically significant difference between the 2 groups (0.014% in vaccine and 0.002% in placebo recipients; odds ratio [OR], 2.70).
• In the entire blinded-phase period after injection, with a median of more than 43 days, the researchers identified no significant difference between the vaccine and placebo groups regarding incident new-onset seizure (0.03% in vaccine and 0.012% in placebo recipients; OR, 2.31).

"According to this systematic review and meta-analysis, we found no statistically significant difference in the risk of new-onset seizure incidence between vaccinated individuals and placebo recipients," the researchers wrote.

In conclusion, the systematic review and meta-analysis offer valuable insights into the safety profile of SARS-CoV-2 vaccines concerning new-onset seizures. With no evidence of an increased risk of seizures associated with vaccination, these findings provide important reassurance to healthcare providers and the general public. Moving forward, continued research and vigilance will be essential in ensuring the safety and effectiveness of COVID-19 vaccines as a cornerstone of global efforts to combat the pandemic.

Reference:

Rafati A, Jameie M, Amanollahi M, et al. Association of New-Onset Seizures With SARS-CoV-2 Vaccines: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. JAMA Neurol. Published online April 29, 2024. doi:10.1001/jamaneurol.2024.0967