Worldwide prevalence of neuromyelitis optica spectrum disorders

Genetic and environmental risk factors are distinct in NMOSD and MS

The prevalence of multiple sclerosis (MS) has been reported from many countries in the world, and prominent geographical differences among regions are well known: over 100 per 100 000 in European and North American populations vs 0–20 per 100 000 in Asian populations. These differences suggest that genetic factors are important in the development of MS. Moreover, it is also known that higher latitude is associated with higher prevalence of MS. The latitude gradient for MS risk is thought to be related to low sun exposure, possibly because this is associated with low serum levels of vitamin D, which has an immunomodulatory effect.

In contrast, data on the prevalence of neuromyelitis optica (NMO) and its wider disease spectrum, NMO spectrum disorders (NMOSD), are scant, although few reports suggest that,1 2 in contrast to MS, the prevalence of NMO is...

from #ORL-AlexandrosSfakianakis via ola Kala on Inoreader http://ift.tt/2EQDrbc