Discontinuation of Immunosuppressive Therapy in Patients With Neuromyelitis Optica Spectrum Disorder With Aquaporin-4 Antibodies

OBJECTIVE: To evaluate the outcomes of immunosuppressive therapy (IST) discontinuation in patients with neuromyelitis optica spectrum disorder (NMOSD) after a sustained remission period. METHODS: We retrospectively reviewed the medical records of 17 patients with antiaquaporin-4 antibody-positive NMOSD who discontinued IST after a relapse-free period of ≥3 years. RESULTS: IST was discontinued at a median age of 40 years (interquartile range [IQR], 32–51) after a median relapse-free period of 62 months (IQR, 52–73). Among the 17 enrolled patients, 14 (82%) relapsed at a median interval of 6 months (IQR, 4–34) after IST discontinuation, 3 (18%) of whom experienced severe attacks; notably, all 3 of these patients had a history of severe attack before IST. These 3 patients received steroids, followed by plasma exchange for acute treatment, but 2 exhibited poor recovery and significant disability worsening at 6 months after relapse. CONCLUSIONS: IST discontinuation may increase the risk of relapse in seropositive patients with NMOSD even after 5 years of remission. Given the potentially devastating consequence of a single attack of NMOSD, caution is advised with IST discontinuation, particularly in patients with severe attack before IST.