Epidemiology and Clinical Characteristics of Neuromyelitis Optica Spectrum Disorders

Neuromyelitis optica spectrum disorders (NMOSD) are rare, relapsing inflammatory diseases of the central nervous system marked primarily by episodes of optic neuritis and transverse myelitis. Epidemiological surveys indicate a prevalence ranging from roughly 1 per 100,000 in White populations to as high as 10 per 100,000 in some Black cohorts, with incidence estimates varying similarly by geography and ethnicity. Women are affected far more commonly than men, particularly in cases associated with aquaporin-4 (AQP4) antibodies, where female:male ratios often exceed 8:1. The average age at onset centres in the fourth decade, although paediatric and late-onset forms also occur. Clinical characteristics include severe, longitudinally extensive spinal cord lesions, bilateral or recurrent optic neuritis and brainstem or area postrema syndromes, all of which can produce substantial disability without prompt immunosuppressive therapy.

Advances in autoantibody detection have refined diagnostic categories into AQP4-antibody-seropositive disease, MOG-antibody-associated disease and double-seronegative cases. AQP4-mediated NMOSD is driven by complement-dependent astrocytopathy, whereas MOG antibody disease reflects primary myelin injury and tends towards differing relapse patterns and outcomes. Mortality and long-term disability remain significant in untreated or under-treated patients, underscoring the importance of early recognition, standardised diagnostic criteria and targeted immunotherapies. Ongoing research explores genetic predisposition, environmental triggers, nutritional modifiers and global incidence trends to inform prevention and management strategies.

Research from Nature Portfolio

A Mendelian-randomisation analysis has suggested that dietary factors may modulate risk in AQP4-positive NMOSD. By leveraging genetic proxies for consumption of 29 food items in a large biobank cohort, investigators found that higher intake of oily fish and raw vegetables was associated with a substantially reduced risk of developing AQP4-antibody-positive disease. These findings have prompted discussion of nutritional interventions as potential adjuncts to conventional immunosuppression, although mechanistic studies are required to clarify causal pathways.

Epidemiology and Clinical Characteristics of Neuromyelitis Optica Spectrum Disorders publication trend

The graph below shows the total number of articles in epidemiology and clinical characteristics of neuromyelitis optica spectrum disorders across all publications each year (not limited to Nature Index journals).

Technical terms

Neuromyelitis optica spectrum disorders (NMOSD): A group of autoimmune conditions causing inflammation of the optic nerves and spinal cord, often associated with specific autoantibodies.

Aquaporin-4 (AQP4) antibody: An IgG autoantibody targeting the water channel AQP4 on astrocytes, serving as a biomarker and pathogenic mediator in NMOSD.

Myelin oligodendrocyte glycoprotein (MOG) antibody: An autoantibody against MOG on the myelin sheath, defining a separate demyelinating syndrome with overlapping features.

Incidence vs Prevalence: Incidence refers to new cases per population over time; prevalence denotes total existing cases in a population at a given time.

Mendelian randomisation: A genetic epidemiology method using inherited genetic variants as proxies to assess causal effects of modifiable exposures on disease risk.

References

1. Sex ratio and age of onset in AQP4 antibody-associated NMOSD: a review and meta-analysis. Journal of Neurology (2024).
2. Characterizing mortality in patients with AQP4‐Ab+ neuromyelitis optica spectrum disorder. Annals of Clinical and Translational Neurology (2024).
3. Oily fish and raw vegetable consumption can decrease the risk of AQP4-positive neuromyelitis optica spectrum disorders: a Mendelian-randomization study. Scientific Reports (2023).
4. Epidemiology of Neuromyelitis Optica Spectrum Disorder and Its Prevalence and Incidence Worldwide. Frontiers in Neurology (2020).
5. Neuromyelitis Optica Spectrum Disorder and Anti-MOG Syndromes. Biomedicines (2019).