Purpose: The aim of this study was to investigate the relationship between vitamin D and novel inflammatory markers in hemodialysis patients.
Methods: In total, 129 eligible maintenance hemodialysis patients were enrolled in this cross-sectional study. Patients were divided into two groups according to their serum vitamin D levels. A serum 25-hydroxyvitamin D (25(OH)D) level < 20 ng/ml was identified as vitamin D deficiency and a serum level ≥ 20 ng/ml was identified as normal. The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were calculated from the complete blood cell count. Spearman correlation analysis and both logistic and linear regression analyses were used to define the relationships between the study parameters.
Results: The two groups showed statistically significant differences for gender and for C-reactive protein (CRP) and NLR values (p = 0.017, p = 0.010, and p = 0.013). Age and gender were independently associated with vitamin D deficiency (p = 0.003 and p = 0.030). Serum 25(OH)D levels showed significant but weak inverse correlations with CRP (r = - 0.205, p = 0.020) and with NLR (r = - 0.219, p = 0.013). Serum 25(OH)D levels also showed a significant but very weak correlation with PLR (r = - 0.182, p = 0.039). Serum 25(OH)D levels showed no correlation with mean platelet volume (p = 0.660). Gender was the only variable significantly associated with serum vitamin D levels, as determined by linear regression analysis (p = 0.003).
Conclusion: CRP levels and NLR values were significantly higher in the vitamin D deficiency group. A significant inverse correlation was found between serum vitamin D levels and CRP levels, and NLR and PLR values.
Keywords: C-reactive protein; Hemodialysis; Inflammation; Neutrophil-to-lymphocyte ratio; Vitamin D.