Rate of Autoimmune Diseases in the 10 Years Preceding Myasthenia Gravis Diagnosis: A Nationwide Cohort Study in South Korea.

The mean age (SD) was 53.7 (16.0) years, and 44.1% were male.

Systemic lupus erythematosus (RR 4.87, 95% CI 2.71-8.77), SjS (RR 4.75, 95% CI 3.01-7.50), autoimmune thyroid disease (RR 3.66, 95% CI 3.29-4.07), and seropositive rheumatoid arthritis (RR 2.45, 95% CI 1.89-3.19) showed the strongest associations.

Psoriasis (RR 1.68, 95% CI 1.25-2.25) and T1DM (RR 2.03, 95% CI 1.52-2.71) were associated with myasthenia gravis only within 0-2 years before diagnosis, whereas Crohn disease and ulcerative colitis were not associated.