The onset location of neuromyelitis optica spectrum disorder predicts the location of subsequent relapses.

We evaluated whether the location of the initial attack predicted the locations of subsequent events in neuromyelitis optica spectrum disorder (NMOSD). In the retrospective analysis from 164 patients with NMOSD, increased odds of a second attack occurring in the initial event location were seen in all locations (odds ratio [OR] brain: 16.00; brainstem: 4.42; optic nerve: 4.08; and spinal cord: 4.59), as was a positive linear trend when evaluating the number of previous events in the same location as the third event location (OR brain: 62.52; brainstem: 44.55; optic nerve: 6.48; and spinal cord: 2.98). This study suggests early clinical events of NMOSD tend to recur in the same anatomical location within the central nervous system (CNS).