Association between Sun Exposure, Vitamin D Intake, Serum Vitamin D Level, and Immunoglobulin G Level in Patients with Neuromyelitis Optica Spectrum Disorder

Background: neuromyelitis optica spectrum disorder (nmosd) is a central nervous system inflammatory disorder in which immunoglobulin g (igg) autoantibodies possibly play a pathogenic role against the aquaporin‑4 water channel protein. vitamin d may modulate b‑cell function and decrease the igg synthesis and may play a role in nmosd as a crucial factor. the aim of this study was to investigate the relation between vitamin d intakes from food, vitamin d intake from sunlight exposure, blood vitamin d levels, and igg‑neuromyelitis optica (nmo) level in serum of patients with nmosd and nmo. method: in this cross-sectional study, food frequency questionnaires (ffq) and sun exposure questionnaire (seq) were completed to evaluate of vitamin d intakes from food and sun light exposure. moreover, serum levels of 25(oh) vitamin d3 and igg-nmo were assessed in patients with nmosd and nmo. results: we assessed igg‑nmo levels in 29 patients with nmosd that nine patients (n = 31%) were positive and for the rest it was negative. sunlight exposure scale (p = 0.01) and 25(oh) d3 (p = 0.04) in igg‑nmo‑negative patients were significantly more than patients with positive igg‑nmo. age, gender, and latitude were not confounder variables. a positive significant correlation was observed between the sun exposure scale and serum levels of 25(oh) d3 in all participants (r = 0.747, p ≤ 0.001). conclusions: physiological variation in vitamin d may apply a significant effect on igg‑nmo synthesis in patients with nmo. vitamin d may have significant role in pathogenesis of nmosd and nmo.