Risk of New-Onset Myasthenia Gravis Following COVID-19 Infection and Vaccination: A Population-Based Case-Control...

Area of Science:

• Neurology
• Immunology
• Epidemiology

Background:

• The relationship between COVID-19 infection/vaccination and myasthenia gravis (MG) is not well-established.
• Investigating new-onset MG following SARS-CoV-2 infection or vaccination is crucial for public health.
• Understanding potential triggers for autoimmune diseases like MG is an ongoing research area.

Purpose of the Study:

• To evaluate the association between COVID-19 infection and new-onset myasthenia gravis (MG).
• To assess the risk of developing MG after receiving the Pfizer-BioNTech COVID-19 vaccine.
• To analyze the temporal relationship between exposure (infection/vaccination) and MG onset.

Main Methods:

• A case-control study utilizing Clalit Health Services database.
• Machine learning (ML) algorithm applied to minimize diagnostic misclassification of MG.
• Analysis of adult new-onset MG cases and matched controls for COVID-19 infection (Cohort I) and Pfizer-BioNTech vaccination (Cohort II) exposure within 90 and 180 days.

Main Results:

• No significant increase in MG risk was observed following COVID-19 infection (OR 1.44 at 90 days, 1.67 at 180 days).
• An elevated risk of new-onset MG was associated with the Pfizer-BioNTech vaccine (OR 1.76 at 90 days, 2.45 at 180 days).
• The association between vaccination and MG was more pronounced within 180 days post-vaccination.

Conclusions:

• COVID-19 infection does not appear to be a significant risk factor for new-onset myasthenia gravis.
• The Pfizer-BioNTech COVID-19 vaccine may be associated with an increased risk of developing myasthenia gravis.
• Further research is warranted to understand the potential mechanisms linking COVID-19 vaccination to MG development.