Guillain-Barré syndrome and COVID-19 vaccination: A systematic review

Background. This systematic review evaluated the studies conducted on Guillain-Barré syndrome (GBS) due to COVID-19 vaccination to clarify any possible connections and the type of vaccines causing GBS. Methods. A comprehensive search was performed on July 2021 through MEDLINE (via PubMed), Scopus, Cochrane, and Web of Science databases to detect published and unpublished papers. Our PICO was all COVID-19 vaccinated individuals as the population, COVID-19 vaccines as the intervention, and patients experiencing GBS following COVID-19 vaccination as the outcome. Critical appraisal instruments from the Joanna Briggs Institute case series or case report were used to evaluate the quality of included studies. Results. In the present systematic review, 12 case reports and case series including 21 patients were assessed. More than half of the patients were male, and the mean age of male patients was lower than females. In terms of vaccine type, the most common kind of vaccine injected was Oxford/AstraZeneca, and all the cases except one patient had received only one dose of the vaccine. Regarding the interval between receiving the vaccine and the onset of GBS symptoms, the mean duration was 14 days. The lowest mean time interval between receiving the vaccine and the onset of symptoms of GBS was related to the unnamed vector-based COVID-19 vaccine, and the highest was associated with Oxford/AstraZeneca. Conclusion. Through this systematic review of case reports, we neither attempt to establish nor rule out a causal link between the COVID-19 vaccine and GBS, because such a link requires extensive case-control studies. However, we must highlight any events that may occur following the injection of existing vaccines. Practical Implications. The most common symptoms seen in patients experiencing GBS after vaccination included progressive bilateral lower limb weakness, paresthesia, numbness of limbs, generalized body aches, and back pain.