Cross-Talk Between Endothelin-1 and Mineral Metabolism in Hemodialysis Patients: A Cross-Sectional Study

BACKGROUND Endotheline-1 (ET-1), an endothelial mediator, influences on mineral metabolism; especially vascular calcification in uremic patients. OBJECTIVES The aim of the present study was to evaluate of ET-1, high-sensitivity C-reactive protein (hs-CRP) and mineral metabolites as the main factors for vascular calcification and inflammation in hemodialysis (HD) patients. PATIENTS AND METHODS In this cross-sectional study, 46 chronic stable HD patients were selected from nephrology departments of Tabriz University of Medical Sciences affiliated hospitals and classified based on phosphorus (P), Ca-P product (Ca × P) and intact Parathyroid Hormone (iPTH) levels. We evaluated fasting serum ET-1and hs-CRP levels by the standard methods and compared with 46 healthy control subjects. RESULTS The levels of serum hs-CRP and ET-1 were significantly higher in the patient's group compared with controls (4.40 ± 1.26 vs. 1.38 ± 1.61, P < 0.0001, and 2.31 ± 0.87 vs. 0.75 ± 0.48, P < 0.0001, respectively) and with regard to Ca × P product cut-off point (3.99 ± 0.78 vs. 5.33 ± 1.64, P < 0.0001, and 2 ± 0.73 vs. 3.04 ± 0.73, P < 0.0001 respectively). ET-1 was correlated significantly with hs-CRP level (r = 0.776, P < 0.0001). Serum P, Ca × P and iPTH levels directly and Ca indirectly were correlated with serum ET-1 in HD patients (r = 0.932, P < 0.0001, r = 0.766, P < 0.0001, r = 0.514, P < 0.0001, r = -0.538, P < 0.0001 respectively). Multiple regression analysis demonstrated that serum P were independently associated with ET-1 levels (β = 0.932, P < 0.0001). CONCLUSIONS Serum P and iPTH levels were independently associated with ET-1 and those may play a role in development of endothelial dysfunction in chronic kidney disease.