25-OH Vitamin D Deficiency in Inflammatory States is not a Reflection of Low Vitamin D Binding Protein Levels Pages 61-65
Jonathan D. Jones and William F. Rigby
Department of Medicine, Section of Rheumatology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
DOI: http://dx.doi.org/10.12970/2310-9874.2014.02.02.5
Download PDFAbstract: Background: Vitamin D binding protein (DBP) levels can profoundly influence 25-OH vitamin D levels. An increased incidence of vitamin D deficiency exists in autoimmune diseases. We hypothesized that low 25-OH vitamin D levels were a reflection of low DBP levels due to the influence of inflammation on hepatic synthesis.
Methods: Serum and plasma samples from patients with inflammatory autoimmune diseases were evaluated for levels of DBP and 25-OH vitamin D. Inflammatory markers high-sensitivity C-reactive protein (hsCRP) and erythrocyte sedimentation rate (ESR) were obtained from the clinical lab. Statistical significance was determined by Spearman correlation.
Results: We identified a broad range of DBP levels (74 to 614 μg/ml) across patients. However, neither DBP nor 25-OH vitamin D levels had any relationship to absolute values of hsCRP or ESR. In addition, in patients with serial samples wherein the inflammatory markers decreased by 25% or more, there was no consistent change in DBP.
Conclusions: DBP levels are unaffected by inflammation, therefore, vitamin D deficiency in autoimmune inflammatory diseases is not simply due to decreased levels of DBP.
Keywords: Vitamin D, Vitamin D binding protein, Inflammation, Autoimmune disease, Rheumatoid arthritis. Read more
