Association between vitamin D serum levels and inflammatory markers in patients on hemodialysis

Introduction: The relationship between 25-OH-vitamin D and the immune system in patients with chronic kidney disease is a subject of attention. Objectives: To assess the prevalence of vitamin D deficiency in patients on hemodialysis and to investigate the association between vitamin D, ultra-sensitive C-reactive protein (US-CRP), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). Method: Cross-sectional study of 80 patients on hemodialysis, divided into two groups: a serum 25-OH-vitamin D level < 20 ng/mL was considered to be vitamin D deficiency and a serum level >= 20 ng/mL was regarded as normal. The relationship between the parameters was defined with Spearman's correlation analysis. Results: 40 % of the patients had vitamin D deficiency. There were significant differences between groups in US-CRP (p = 0.047), NLR (p = 0.039), PLR (p = 0.042) and treatment with vitamin D analogues (p = 0.022). Vitamin D had a significant negative correlation with US-CRP (p = 0.026), NLR (p = 0.013) and PLR (p = 0.022). Conclusions: The prevalence of vitamin D deficiency was 40 %. The values of US-CRP, NLR and PLR were significantly higher in the presence of vitamin D deficiency. A significant inverse correlation was found between vitamin D levels and US-CRP, NLR and PLR.