Serum antinuclear antibodies associate with severe disease activity in neuromyelitis optica spectrum disorder

Studies suggest that antinuclear antibodies (ANAs) may correlate with the long-term prognosis of Neuromyelitis optica spectrum disorder (NMOSD). In this study, we investigated ANAs in Chinese patients with NMOSD and their relationship with disease outcomes.We retrospectively collected data from 525 patients diagnosed with NMOSD at West China Hospital between September 1, 2009, and October 1, 2021. Patients were classified into two groups: NMOSD with ANA (+) or without ANA (-). We compared the clinical characteristics, relapse rate, severe attacks, laboratory tests, Expanded Disability Status Scale (EDSS), and prognosis between the two groups.Among the 525 NMOSD patients, those with ANA showed a higher frequency of AQP4-IgG (94.1% vs 79.3%, p < 0.001, false discovery rate (FDR) corrected p < 0.001), and anti-SSA (p < 0.001, FDR corrected p < 0.001), anti-SSB (p < 0.001, FDR corrected p < 0.001), anti-Ro52 antibodies (p < 0.001, FDR corrected p < 0.001), than those without ANA. ANA was detected in 403 patients during the acute phase. Patients with ANA (+) had higher EDSS scores in the acute stage (4.0 vs. 3.75, p = 0.013, FDR corrected p = 0.029) and at final follow-up (p = 0.032, FDR corrected p = 0.064). NMOSD patients with ANA (+) had a higher frequency of severe acute myelitis attack, severe acute myelitis and optic neuritis attack, motor and visual disability, compared to those with ANA (-) (42.1% vs. 27.8%, p = 0.001, FDR corrected p = 0.004, 19.3% vs. 10.3%, p = 0.004, FDR corrected p = 0.018, and 11.1% vs. 4.8%, p = 0.008, FDR corrected p = 0.022 respectively). The two groups had no significant difference in the annual recurrence rate (ARR).ANA may be associated with more severe disease activity and disability in NMOSD.