Association of Seizure with COVID-19 Vaccines in Persons with Epilepsy: A Systematic Review and Meta-analysis

Objective: Seizure following immunization, especially in persons with epilepsy (PwE), has long been a concern, and seizure aggravation followed by Coronavirus Disease 2019 (COVID-19) vaccines is a serious issue for PwE. The immunization rate in PwE has been lower compared to same-age controls due to vaccine hesitancy and concerns about seizure control. Herein, we systematically reviewed the seizure activity-related events in PwE following COVID-19 vaccination. Methods: Four search engines were searched from inception until January 31, 2023, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses was followed. Random- and fixed-effect models using the logit transformation method were used for meta-analysis. The quality of the studies was evaluated by the Newcastle-Ottawa scale. Outcomes of interest included (a) pooled proportion of increased seizure frequency and (b) pooled incidence proportion of status epilepticus (SE) in PwE receiving COVID-19 vaccines. Results: Of the 2207 studies identified, 18 met eligibility criteria, of which 16 entered the meta-analysis. The pooled proportion of increased seizure frequency (16 studies-4197 PwE) was 5% (95CI: 3%-6%, I2 =57%), further subcategorized into viral vector (3%, 95CI: 2%-7%, I2 =0%), mRNA (5%, 95CI: 4%-7%, I2 =48%), and inactivated (4%, 95CI: 2%-8%, I2 =77%) vaccines. The pooled incidence proportion of SE (15 studies-2480 PwE) was 0.08% (95CI: 0.02%-0.32%, I2 =0%), further subcategorized into the viral vector (0.00%, 95CI: 0.00%-1.00%, I2 =0%), mRNA (0.09%, 95CI: 0.01%-0.62%, I2 =0%), and inactivated (0.00%, 95CI: 0.00%-1.00%, I2 =0%) vaccines. No significant difference was observed between mRNA and viral vector vaccines (5 studies, 1122 vs. 198 PwE, respectively) regarding increased seizure frequency (OR: 1.10, 95CI: 0.49-2.50, p-value=0.81, I2 =0%). Significance: The meta-analysis proposed a 5% increased seizure frequency following COVID-19 vaccination in PwE, with no difference between mRNA and viral vector vaccines. Furthermore, we found a 0.08% incidence proportion for SE. While this safety evidence is noteworthy, this cost should be weighed against vaccination benefits.