OBJECTIVES: To assess how Neuromyelitis Optica Spectrum Disorder (NMOSD) relapses impact patients’ physical health and functioning. NMOSD is a rare, complement-mediated, autoimmune disease characterised by unpredictable severe relapses which often attack and permanently damage the spinal cord and optic nerve.

METHODS: Analysis was conducted using data collected from the Adelphi NMOSD Disease Specific Programme (DSP), a cross-sectional and retrospective survey of physicians and their patients in the UK, France, Spain, Italy, and Germany January-May 2023. Descriptive analyses with significance testing were performed.

RESULTS: Physician-reported data was available for 374 NMOSD patients. Of these patients, 106 (28%) were reported by their physician to have experienced relapses (65% 1 relapse, 16% 2 relapses, 19% 3+ relapses) following their initial attack; 217 (58%) were reported to have not experienced a relapse. The time since last relapse was a mean of 3.3 years and a median of 1.9 years, with relapsing patients being diagnosed with NMOSD longer ago than non-relapsing patients (median of 3.5 vs 1.5 years, mean of 5.3 vs 3.1 years. Compared with non-relapsing patients, relapsing patients had significantly higher rates of: blindness in one eye (11.1% vs 4.2%, p=0.017), blindness in both eyes (5.6% vs 0.4%, p=0.003), muscle weakness (54.6% vs 40.8%, p=0.016), muscle atrophy (13.0% vs 4.5%, p=0.006), bladder control deficit (40.7% vs 23.0%, p=0.001), bowel control deficit (12.0% vs 5.3%, p=0.028), nociceptive deficit (decreased pain reception; 15.7% vs 7.2%, p=0.019) and seizures (2.8% vs 0.0%, p=0.024).

CONCLUSIONS: Results demonstrate the real-world negative and debilitating impact of NMOSD relapses on patients. This highlights the need for early diagnosis and early, effective treatment intervention to minimise relapse risk.