ABSTRACT Purpose Spontaneous reporting of a possible link between myelin oligodendrocyte glycoprotein ( MOG ) antibody‐associated disease ( MOGAD ) and mRNA SARS ‐ CoV ‐2 vaccination warrants further examination. Hence, the objective of this study was to investigate the association between MOG ‐ IgG positivity as a proxy for MOGAD and mRNA SARS ‐ CoV ‐2 vaccination in the Danish population. Methods We applied the self‐controlled case series study using Danish nationwide health registers. The study population consisted of all Danish residents who were offered an mRNA COVID ‐19 vaccination and had a first positive MOG ‐ IgG test result between November 1, 2020 to December 31, 2023. Results Among 5.9 million individuals eligible for SARS ‐ CoV ‐2 vaccination, we identified 111 incident events of MOG ‐ IgG positivity in the study period of which 28 (25%) occurred in children. We found no association between mRNA SARS ‐ CoV ‐2 vaccination and MOG ‐ IgG positivity in adults, but an increased risk—although based on small numbers—was found in children below 18 years of age (incidence rate ratio = 8.07, 95% confidence intervals: 3.07–21.21). If the observed association reflects a causal effect, the estimated number of excess MOG ‐ IgG positive events attributable to mRNA COVID ‐19 vaccination in Denmark was 4.38 per 1 000 000 exposed children. Conclusions These results suggest an increased risk of MOG ‐ IgG positivity after mRNA SARS ‐ CoV ‐2 vaccination in children, but not in adults. The number of additional MOGAD events attributable to mRNA SARS ‐ CoV ‐2 vaccination in children is very low and further studies are needed to confirm these findings.
Kopp et al. (Sun,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: