25-Hydroxyvitamin D Concentrations in Patients with Optic Neuritis as a Clinically Isolated Syndrome and Healthy Controls

Objectives: the onset of multiple sclerosis in the majority of thecases occurs as a clinically isolated syndrome (cis). we soughtto assess serum levels of 25-hydroxyvitamin d (25-ohd) in cispatients and healthy controls.methods: in this cross-sectional study 40 patients (36 women and4 men) with cis manifesting as a single isolated optic neuritis and40 age- and sex-matched healthy controls (35 women and 5 men)were enrolled between late october 2010 and early march 2011.general vitamin d deficiency was defined as serum 25-ohd levelsof lower than 20 ng/ml and was classified as mild (15 < 25-ohd < 20 ng/ml), moderate (8 < 25-ohd < 15 ng/ml), and severe (25-ohd < 8 ng/ml).results: we found no difference in the median interquartilerange [iqr] between cis patients and controls (17.95 [10.40-29.13] vs. 17.00 [12.25-31.00]; p=0.57). however, when stratifiedby the levels of deficiency, among cis patients a significantlyhigher proportion had severe vitamin d deficiency in comparisonto healthy controls (20% vs. 2.5%; p=0.034). nevertheless, thefrequency of general (62.5% vs. 60%, p=0.82), mild (25% vs.30%, p=0.80), and moderate (17.5% vs. 27.5%, p=0.42) vitamin ddeficiency were not different between the two groups.conclusions: our findings do not indicate any significantdifference of serum 25-ohd between cis patients and healthycontrols. however, in our series severe vitamin d deficiency wasmore frequent among cis patients.