Optic neuritis in an ethnically diverse population: higher risk of atypical cases in patients of African or African-Caribbean heritage.

Purpose: To investigate the presence of an ethnicity bias within patients presenting with optic neuritis in London.

Design: Observational cross-sectional study.

Methods: The ethnicity profile of all patients attending a neuro-ophthalmology clinic in central London with acute optic neuritis over a 16month period (n=86) was studied. A comparison was made with the ethnicity profile of the population of London as well as patients with Multiple Sclerosis-associated optic neuritis (n=41), Neuromyelitis Optica spectrum disorder-associated optic neuritis (n=27) and patients with an atypical corticosteroid-dependent optic neuropathy (21).

Results: The ethnicity profile of the patient cohort presenting to our clinic with acute optic neuritis over a 16 month period closely matched the ethnicity profile of London (P=0.08). Within this cohort, patients of African or African-Caribbean heritage were found to be more likely to manifest either a pattern or aetiology of optic neuritis requiring immunosuppressive treatment in comparison with patients of a white Caucasian background (relative risk 3.47; 95% CI=1.092 to 11.007). There was a disproportionately high representation of patients from an African or African-Caribbean background within the Neuromyelitis Optica spectrum-related optic neuritis diagnostic group (P<0.00).

Conclusions: Patients with acute isolated optic neuritis from African or African Caribbean backgrounds are over 3 times more likely than patients of white Caucasian backgrounds to have an 'atypical' pattern of optic neuritis where corticosteroid therapy may be required. Our results suggest that a patient's ethnic background is an important factor to be taken into consideration when deciding on the diagnosis and management of acute isolated optic neuritis.