title: Vitamin D and inflammation: evaluation with neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio.
abstract: BACKGROUND
  Association of vitamin D, inflammation and endothelial dysfunction, beside the classic bone metabolism disorders, may explain the pathogenesis of numerous diseases associated with vitamin D deficiency. While large numbers of reports support the relationship of vitamin D with inflammation, several reports fail to confirm this relationship. Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are novel and inexpensive markers of inflammation that can be studied in all centers. The goal of this study was to investigate the association between 25-hydroxy vitamin D (25(OH)D) and inflammation with the novel inflammatory markers NLR and PLR.
  
  
  METHODS
  This study was performed retrospectively. Results of the simultaneously performed 25(OH)D, parathyroid hormone, albumin, calcium, phosphorus, alkaline phosphatase and creatinine level measurements and complete blood count were recorded. The data of 4120 patients were included in the study.
  
  
  RESULTS
  Between vitamin D deficient and non-deficient groups there were significant differences in PLR (p < 0.001) and NLR (p = 0.001). Vitamin D had a significant negative correlation with PLR (p < 0.001) and NLR (p < 0.001). Multiple regression analysis indicated that 25(OH)D was independently and negatively correlated with PLR (OR = 0.994, 95% CI 0.991-0.998, p = 0.02).
  
  
  CONCLUSIONS
  Platelet-to-lymphocyte ratio and NLR were significantly associated with 25(OH)D levels, and PLR was found to be an independent predictor of 25(OH)D levels. Our study revealed an inverse association of vitamin D levels and inflammation with these inexpensive and universally available markers.
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Erzincan University, Erzincan, Turkey.
authors.forename: Emin Murat
authors.initials: EM
authors.lastname: Akbas
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Atatürk University, Erzurum, Turkey.
authors.forename: Adem
authors.initials: A
authors.lastname: Gungor
authors.affiliation: Department of Internal Medicine, Erzincan University, Erzincan, Turkey.
authors.forename: Adalet
authors.initials: A
authors.lastname: Ozcicek
authors.affiliation: Department of Biochemistry, Atatürk University, Erzurum, Turkey.
authors.forename: Nergis
authors.initials: N
authors.lastname: Akbas
authors.affiliation: Department of Biochemistry, Atatürk University, Erzurum, Turkey.
authors.forename: Seda
authors.initials: S
authors.lastname: Askin
authors.affiliation: Department of Internal Medicine, Atatürk University, Erzurum, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Polat
keywords: endothelial dysfunction; inflammation; vitamin D