Background: Apelin, a newly discovered adipocytokine, is produced by white adipose tissue and is also expressed in the kidney and heart. Increasing evidence suggests a role for apelin in the pathology of the cardiovascular system. Cardiovascular disease is a major contributor to the mortality and morbidity in patients with chronic renal failure. The aim of this study was to assess associations between apelin, coronary artery disease (CAD) and echocardiographic parameters in hemodialyzed patients. Patients and Methods: We investigated plasma apelin levels (using commercially available kits) in 81 nondiabetic, clinically stable hemodialyzed patients (38 females, 43 males) with and without CAD. Results: Patients with CAD were significantly older, with significantly increased left ventricular internal end-diastolic dimension (LVIDd), left ventricular internal end-systolic dimension (LVISd), right ventricle (RV), left atrium (LA), interventricular septum in diastole, left ventricle posterior wall in diastole (LVPW), aorta, pulmonary artery, significantly lower ejection fraction and apelin than patients without CAD. We observed statistically significant correlations between apelin and echocardiographic parameters: LVIDd, LVISd, RV, LA, right atrium, LVPW, aorta, and serum lipids: cholesterol, LDL, triglycerides. In multiple logistic regression analysis, the only associate of apelin was LVIDd. Conclusions: Apelin level was significantly lower in dialyzed patients with CAD and it was associated with cardiac function. Apelin might be involved in the pathophysiology of cardiovascular disease in chronic renal failure. Since apelin is an inotrope in normal and failing hearts, this finding may have clinical implications for future use of apelin as a novel inotropic agent also for patients with uremic cardiomyopathy.

Our preliminary results suggest that renalase, probably due to the sympathetic nervous system hyperactivity, could be associated with hypertension and cardiovascular complications, including stroke in hemodialyzed patients. However, further studies are needed to establish the possible role of renalase in these complications. Renalase is "a new postulated therapeutic target."

Background. The evidence base regarding the safety of intravenous (IV) iron therapy in patients with chronic kidney disease (CKD) is incomplete and largely based on small studies of relatively short duration. Methods. FIND-CKD (ClinicalTrials.gov number NCT00994318) was a 1-year, open-label, multicenter, prospective study of patients with nondialysis-dependent CKD, anemia and iron deficiency randomized (1:1:2) to IV ferric carboxymaltose (FCM), targeting higher (400–600 µg/L) or lower (100–200 µg/L) ferritin, or oral iron. A post hoc analysis of adverse event rates per 100 patient-years was performed to assess the safety of FCM versus oral iron over an extended period. Results. The safety population included 616 patients. The incidence of one or more adverse events was 91.0, 100.0 and 105.0 per 100 patient-years in the high ferritin FCM, low ferritin FCM and oral iron groups, respectively. The incidence of adverse events with a suspected relation to study drug was 15.9, 17.8 and 36.7 per 100 patient-years in the three groups; for serious adverse events, the incidence was 28.2, 27.9 and 24.3 per 100 patient-years. The incidence of cardiac disorders and infections was similar between groups. At least one ferritin level ≥800 µg/L occurred in 26.6% of high ferritin FCM patients, with no associated increase in adverse events. No patient with ferritin ≥800 µg/L discontinued the study drug due to adverse events. Estimated glomerular filtration rate remained the stable in all groups. Conclusions. These results further support the conclusion that correction of iron deficiency anemia with IV FCM is safe in patients with nondialysis-dependent CKD.

Elevated resistin related to markers of inflammation may represent a novel link between inflammation and adipocytokines in HD patients. Impaired renal function and inflammation are responsible for elevated resistin in HD patients.

Neutrophil gelatinase-associated lipocalin (NGAL) has recently been proved useful in the quantitation of chronic kidney disease. A cross-sectional study was performed to assess NGAL in serum, urine and ultrafiltrate in relation to the type of renal replacement therapy and NGAL correlations with renal function and markers of inflammation. Methods: NGAL, hsCRP, TNFα, and IL-6 were measured using commercially available kits in 200 patients on hemodialysis (HD), 17 on hemodiafiltration (HDF). Results: Patients on HDF had lower serum NGAL than those on HD. In hemodialyzed patients with residual renal function, serum NGAL was significantly lower than in anuric patients. NGAL was significantly higher in patients dialyzed on modified cellulose dialyzers versus polysulphone dialyzers. NGAL correlated with age, residual renal function, hsCRP, IL-6, TNF-α, time on HD, ferritin, TSAT, creatinine, urea, urea reduction ratio, and Kt/V in hemodialyzed patients. In multiple regression analysis, residual renal function and hsCRP were predictors of NGAL in hemodialyzed patients. NGAL correlated with hsCRP and creatinine in HDF patients. Conclusions: Residual renal function seems to play a pivotal role in NGAL levels in dialyzed patients. Low-grade inflammation, more pronounced in anuric patients may also contribute to elevated NGAL. Removal of NGAL with ultrafiltrate may also partially explain its lower concentration after dialysis.