Low vitamin D-25(OH) level in Indonesian multiple sclerosis and neuromyelitis optic patients

•Vitamin D level was low in Indonesian MS and NMO patients.•No significant association between serum vitamin D 25(OH) level and disease severity in MS and NMO patients.•Low level of serum vitamin D should be anticipate in MS or NMO patients who received corticosteroid treatment. Vitamin D deficiency is commonly found in multiple sclerosis (MS) and Neuromyelitis Optic (NMO) patients and can impair the immunological status. As a tropical country, Indonesia has a lot of sunshine throughout the year as a source of vitamin D. The aim of this study was to evaluate and compare the serum vitamin D-25(OH) level in Indonesian MS and NMO patients to healthy individuals. A cross-sectional study was conducted in Dr. Cipto Mangunkusumo General Hospital Jakarta from November 2016 to May 2017. Forty-eight patients (29 MS and 19 NMO) and 33 healthy controls were enrolled. We assessed the dietary recall, vitamin D supplementation, sunshine exposure, medication, annual relapse rate, and Expanded Disability Status Scale (EDSS). Vitamin D level was measured using direct competitive chemiluminescence immunoassay. Vitamin D deficiency was found in 48.4% of MS and 56.2% of NMO patients. The serum vitamin D level in MS and NMO groups was not significantly different from the healthy controls. Vitamin D level was not associated with EDSS and the annual relapse rate. Positive significant correlation was observed between sunshine exposure and vitamin D level in healthy control, but not evident in MS and NMO groups. MS and NMO subjects who still treated with corticosteroid had lower vitamin D level. Vitamin D deficiency is commonly found in Indonesian MS and NMO patients, but not associated with EDSS and annual relapse rate. Despite living in a country with adequate sunshine exposure, the physician should anticipate low serum vitamin D level, especially in MS or NMO patients who received corticosteroid.