Are PTH levels related to oxidative stress and inflammation in chronic kidney disease patients on hemodialysis?

INTRODUCTION: Patients at end stage renal disease have higher levels of inflammation and oxidative stress than the general population. Many factors contribute to these issues, and the parathyroid hormone (PTH) is also implicated.
OBJECTIVE: The study was conducted in order to assess the relationship between PTH levels and inflammation and oxidative stress in hemodialysis patients.
METHODS: Cross-sectional study with patients of two hemodialysis facilities in Londrina, Brazil. Patients with other conditions known to generate oxidative stress and inflammation were excluded. Blood levels of PTH and biochemical parameters of inflammation (interleukins 1 and 6, tumor necrosis factor-alpha) and oxidative stress (total plasma antioxidant capacity, malonic dialdehyde, lipid hydroperoxidation, advanced oxidation protein products, quantification of nitric oxide metabolites, and 8-isoprostane) were measured before a dialysis session. Then, we made correlation analyses between PTH levels - either as the continuous variable or categorized into tertiles-, and inflammatory and oxidative stress biomarkers.
RESULTS: PTH did not show any correlation with the tested inflammation and oxidative stress parameters, nor as continuous variable neither as categorical variable.
CONCLUSION: In this descriptive study, the results suggest that the inflammation and oxidative stress of hemodialysis patients probably arise from mechanisms other than secondary hyperparathyroidism.