Prevalence and Relative Proportions of Multiple Sclerosis, Neuromyelitis Optica Spectrum Disorder, and Myelin Oligodendrocyte Glycoprotein Antibody–Associated Disease in the Republic of Korea

초록

Objectives To provide the clinically validated, nationwide estimates of multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody–associated disease (MOGAD) in Korea, and to describe their relative proportions. Methods From January to March 2025, 47 referral hospitals participating in a nationwide hospital-based registry identified actively followed patients with MS, NMOSD, or MOGAD. Diagnoses followed international criteria, and antibody status was confirmed using validated CBAs. Actively followed patients had ≥1 outpatient visit in the prior 6 months. Centers provided demographics, treatments, and Expanded Disability Status Scale. Prevalence used national population data. Results A total of 4,196 patients were identified, 1,799 MS, 1,616 NMOSD, and 781 MOGAD (ratio 2.3:2.1:1). Mean age at onset was 33.4 ± 12.0 years for MS, 42.7 ± 14.7 for NMOSD,and 41.7 ± 17.8 for MOGAD,and the female-to-male ratios were 2.2:1 for MS, 5.1:1 for NMOSD (6.5:1 in aquaporin-4-IgG positive cases),and 1.5:1 for MOGAD. Crude prevalence estimates were 3.48, 3.13, and 1.51 per 100,000, respectively. Discussion This nationwide registry demonstrates a distinctive Korean CNS inflammatory demyelinating disease profile, with a relatively higher proportion of NMOSD and MOGAD reflecting the low prevalence of MS in East Asia.