Rheumatoid Factor May Associated with Disability in Neuromyelitis Optica Spectrum Disorder

Abstract

Background: Neuromyelitis optica spectrum disorder (NMOSD) was rare neuroinflammatory disease, often coexists with autoantibodies such as anti-nucleotide antibody (ANA), anti-Sjogren’s syndrome A (SSA) antibody, anti-Sjogren’s syndrome B (SSB) antibody, and rheumatoid factor (RF). However, the relationship between autoantibodies and NMOSD is not clear. Objective: We investigated the prevalence of autoantibodies and the associations between the existence of autoantibodies and disability in NMOSD patients. Methods: We collected the clinical information and the profile of autoantibodies including ANA, SSA, SSB, anti-neutrophil cytoplasmic antibody (ANCA), anti-thyroperoxidase (TPO) antibody, anti-thyroglobulin (TG) antibody, and RF in NMOSD patients of 11 hospitals in Korea for 3 years (2014. Sep – 2016. Nov). We evaluated the associations between the positivity of each autoantibody and the time from onset of NMOSD to a higher Expanded Disability Status Scale (EDSS) score (EDSS>6.0) using coxregression analysis. Results: A total of 159 patients were evaluated autoantibodies, the frequency of autoantibodies was ANA (33%), SSA (29%), TPO (15%), TG (12%), SSB (10%), RF (9%), and ANCA (2.4%). The median of EDSS was 3 (IQ 2-4), the mean of disease duration was 8.2 (SD 6.5) years. Higher EDSS was associated the elevation of RF (p=0.003) and the hazard ratio of RF was 7.9 (95% CI 2.0 – 31.1). Conclusion: Autoantibodies possibly modulate the progression of disease in NMOSD. We confirmed that various autoantibodies were presented and suggested that the elevation of RF may be associated the higher disabilities in NMOSD patients.