Schizophrenia, Vitamin D and autoimmunity - Are low serum Vitamin D levels related to immune system abnormalities? New aspects and review of the litera

Aims: Vitamin D is increasingly associated with the pathology of cognition and mental illness. Vitamin D receptors have been detected on neurons that regulate behaviour. The aim of this study was to assess vitamin D serum concentrations in patients with major depression and schizophrenia compared to healthy controls and to determine if a correlation exists between serum levels of vitamin D and disease activity. Methods: We recruited 50 patients with schizophrenia and as comparators we enrolled 33 patients with major depression and 50 controls with no major psychopathology. The Positive and Negative Syndrome Scale (PANSS) for schizophrenia and the Hamilton Depression scale for depression were administered at the same day the blood samples were drawn. We used LIAISON® 25 OH Vitamin D (DiaSorin) Immunoassay, to measure serum concentrations of 25 OH Vitamin D. Results: Lower serum vitamin D concentrations were detected among patients with schizophrenia (15.0±7.3 ng/ml) compared to patients with depression (19.6±8.3ng/ml) and to controls (20.2±7.8 ng/ml, p< 0.05).We found no correlation between disease activity, measured by the PANSS score and vitamin D levels. Conclusions: Lower serum vitamin D levels were found in patients with schizophrenia compared to patients with depression and to healthy controls. No correlation was found between serum concentration and disease activity. Additional studies are needed to elucidate the role of vitamin D in the autoimmune mechanism and in the pathogenesis of schizophrenia.