Prevalence of cardiovascular diseases in kidney transplant recipients and its relationship with asymmetric dimethylarginine, fibroblast growth factor-23 and multiple inflammatory markers.

Abstract

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide synthase, a marker of endothelial damage and progression of atherosclerosis. Research confirms the association of ADMA with an increased risk of cardiac complications and an increased risk of death, graft loss among kidney transplant recipients (KTRs). The aim of our study was to establish the significance of ADMA and FGF-23 as biomarkers of cardiovascular risk as well as predictors of graft failure and progression of chronic transplant kidney disease in comparison to CKD subjects. In addition, an analysis of the relationship between ADMA, FGF23 and cardiovascular diseases in CKD subjects and KTRs was performed. The study group included 132 KTRs. The control group consisted of age- and sex-adjusted 40 individuals with clinically stable CKD. ADMA, FGF-23, hs-CRP and IL-6 were measured by the enzyme-linked immunoassay method (ELISA). Parameters of body mass composition such as fat mass, FTI, lean tissue mass, LTI, body water and overhydration were assessed by multi-frequency bioimpedance analysis (BIA). Cardiovascular diseases (CVDs) were present in 31.8% of KTRs. Independent variables related to nutritional status (SGA, s-albumin), according to multivariate regression, may have an impact on the prevalence of CVD in the kidney transplant recipients' group. Our study findings suggested a correlation between ADMA and serum albumin (r=-0.41, p<0.05), oxLDL (r=-0.42, p<0.05) and overhydration (OH%, r=0.28, p<0.05). Moreover, administration of statins and/or angiotensin-converting-enzyme inhibitors was significantly related to a reduction of ADMA in KTRs. We have also identified a significant positive correlation between FGF-23 levels and inflammatory markers (hs-CRP, IL-6) and negative with overall index of renal function (eGFR-CKD EPI, eGFR-MDRD). Nutritional status, inflammation and endothelial dysfunction markers (ADMA, FGF-23) are considerably altered even in stable kidney transplant recipients.