Associations of neuralgic amyotrophy with COVID-19 vaccination: Disproportionality analysis using the World Health Organization pharmacovigilance database

Introduction/Aims: There are limited studies on the association of COVID-19 vaccination with neuralgic amyotrophy (NA). Therefore, we evaluated the association between COVID-19 vaccination and the occurrence of NA. Methods: We explored unexpected safety signals for NA related to COVID-19 vaccination through disproportionality analysis using VigiBase, the World Health Organization's pharmacovigilance database. Results: On October 15, 2021, 335 cases of NA were identified in the database. The median time to onset of NA after vaccination was around 2 weeks. A significant signal of disproportionality of NA was observed for the ChAdOx1 nCoV-19 vaccine (AstraZeneca) (information component [IC]₀₂₅ = 0.33, reporting odds ratio [ROR]₀₂₅ = 1.30) and two mRNA-based COVID-19 vaccines (BNT162b2 [Pfizer and BioNTech] and mRNA-1273 [Moderna]) (IC₀₂₅ = 1.74, ROR₀₂₅ = 3.82) compared with the entire database. However, when compared with influenza vaccines, we did not detect any signal of disproportionality of NA for both the ChAdOx1 nCoV-19 vaccine (IC₀₂₅ = −2.71, ROR₀₂₅ = 0.05) and mRNA-based COVID-19 vaccines (IC₀₂₅ = −1.38, ROR₀₂₅ = 0.13). Discussion: A weak association was observed between NA and COVID-19 vaccines. However, the risk did not surpass that of influenza vaccines.