OPTIC NEURITIS IN AFRICAN-AMERICANS

Objective: To describe the clinical profile of demyelinating optic neu ritis in African Americans. Methods: The medical records of all patien ts with a diagnosis of optic neuritis examined at the Neuro-Ophthalmol ogy Unit at the Emery University Eye Center (Emery) and at the Grady M emorial Hospital Eye Clinic (Grady), Atlanta, Ga, between 1989 and 199 6 were retrospectively reviewed. Patients: African American and white patients, aged 15 through 55 years, with a single initial episode of a cute optic neuritis of unknown or demyelinative origin were included i n the study. Study patients included 23 African American patients and 56 white patients examined at Emery as well as 10 African American pat ients examined at Grady. Results: There were no significant difference s among the African American study patients, the white study patients, and patients from the Optic Neuritis Treatment Trial (ONTT) regarding sex (P=.36), age (P=.73), or the presence of disc edema (P=.40), lesi ons found on magnetic resonance imaging (P=.43), or multiple sclerosis (P=.54) at the onset of an initial episode of optic neuritis. The Eme ry African American patients presented with more frequent severe visua l loss (13 [93%] of 14 patients with a visual acuity less than or equa l to 20/200) compared with Emery white patients (12 [39%] of 31 patien ts; P=.002) and with ONTT patients (161 [36%] of 448 patients; P<.001) . At follow-up examination of at least 1 year, Emery African American patients had worse vision (9 [39%] of 23 patients <20/40, and 4 [17%] of 23 patients less than or equal to 20/200) compared with Emery white patients (5 [8%] of 63 patients <20/40, P=.001; 3 [5%] of 63 patients less than or equal to 20/200, P=.08), and with ONTT patients (29 [7%] of 409 patients <20/40, P=.0001; 12 [3%] of 409 patients less than or equal to 20/200, P=.01). Compared with ONTT patients, the Emery Afric an American patients combined with the Grady African American patients had more frequent severe visual loss (visual acuity less than or equa l to 20/200) at presentation (18 [90%] of 20 patients vs 161 [36%] of 448 patients; P<.001) and at follow-up examination of at least 1 year (6 [18%] of 33 patients vs 12 [3%] of 409 patients; P=.002). Seven (58 %) of 12 African American patients with multiple sclerosis had a ''neu romyelitis optica'' presentation defined by the presence of neurologic al deficits limited to the optic nerves and spinal cord. Conclusions: The African American study patients with a single episode of demyelina ting optic neuritis had visual acuities more severely affected at onse t and after 1 year of follow-up compared with the white study patients and with patients in the ONTT. In the African American patients, mult iple sclerosis occurred most frequently in a ''neuromyelitis optica'' form.