Ghrelin and acyl ghrelin levels are associated with inflammatory and nutritional markers and with cardiac and vascular dysfunction parameters in hemodialysis patients.

PURPOSE: Exogenous ghrelin is associated with cardiovascular protection in experimental and human studies. Nevertheless ESRD patients have increased ghrelin levels and severe cardiovascular comorbidities. This study aims to elucidate the metabolic factors influencing endogenous ghrelin/acyl ghrelin levels and to analyze the relation between endogenous ghrelin/acyl ghrelin levels and cardiac and vascular function markers in hemodialysis patients. METHODS: The cross-sectional study was conducted in hemodialysis patients (n = 88); 50 of them were men, mean age 61.1 ± 13.5 years, 17% had diabetes. We assessed nutritional and inflammatory status and analyzed the determinants of ghrelin/acyl ghrelin and their relation with cardiac and vascular function. RESULTS: Ghrelin is correlated with IL-1ß (r = 0.88, p < 0.0001), triglycerides, total cholesterol (TC), and Kt/V. IL-1ß is the strongest predictor of ghrelin levels (p < 0.0001). Acyl ghrelin is correlated with TC (r = 0.36, p = 0.001), LDL-cholesterol, serum bicarbonate, body mass index. TC is the strongest predictor for acyl ghrelin levels (p = 0.038). Patients with high ghrelin levels had significantly decreased nitroglycerin-mediated dilation (p = 0.05) and higher IL-1ß levels (p < 0.001); increased NT-proBNP is associated with lower levels of acyl ghrelin (r = - 0.33, p = 0.02) in male patients. CONCLUSION: The inflammatory marker IL-1ß is in our study the strongest predictor of ghrelin levels while the nutritional marker-total cholesterol is the strongest predictor for acyl ghrelin levels in HD patients. High endogenous ghrelin level is associated with high IL-1ß and with vascular smooth muscle cell dysfunction. Low acyl ghrelin level is associated with high NT-proBNP (a cardiac dysfunction marker) in male HD patients. There is a direct correlation between endogenous ghrelin level and inflammatory markers, which is not related with cardiovascular protection.

Matrix-Metalloproteinase-2 Predicts Arteriovenous Fistula Failure in Hemodialysis Patients.

In hemodialysis patients the principal cause of arteriovenous fistula dysfunction is stenosis. Matrix-metalloproteinase-2 is implicated in the pathophysiological mechanism of stenosis development. Our study tried to assess the clinical impact of this protease on arteriovenous fistula survival. Seventy-nine prevalent dialysis patients with functional arteriovenous fistulas were included in the study. The presence of stenosis and the serum levels of matrix-metalloproteinase-2 were determined at the beginning of the study. The patency of the arteriovenous fistulas was followed- up for two years. In multivariate regression; matrix-metalloproteinase-2 was a significant predictor of vascular access loss (HR = 1.104, 95%CI 1.033-1.179, P = 0.003). Patients with a level of matrix-metalloproteinase-2 lower than 50 ng/mL had a better survival of the arteriovenous fistulas. Matrix-metalloproteinase-2 was an even stronger predictor of fistula failure in the stenosis group (HR = 1.076, 95%CI 1.027-1.127, P = 0.002). In our study matrix-metalloproteinase-2 has a predictive value for arteriovenous fistula failure.

Insomnia, muscular cramps and pruritus have low intensity in hemodialysis patients with good dialysis efficiency, low inflammation and arteriovenous fistula.

INTRODUCTION: Insomnia, muscular cramps, pruritus and postdialysis recovery time (RT) are quality-of-life parameters that affect hemodialysis (HD) patients physically and mentally. METHODS: We included 171 end-stage renal disease patients: 115 on high-flux HD and 56 on online hemodiafiltration (HDF). Patients were asked "How long does it take you to recover from a dialysis session?" and they evaluated intensity (absent, mild, medium and severe) of insomnia, muscular cramps and pruritus in the past 4 weeks. We sought associations of RT, insomnia, muscular cramps and pruritus with themselves and age, dialysis vintage, sex, body mass index, hemoglobin, albumin, C-reactive protein (CRP), Daugirdas single-pool Kt/V (Kt/V), ultrafiltration volume, blood processed volume and vascular access type. RESULTS: Insomnia absence correlated with muscular cramps absence (p = 0.01), arteriovenous fistula (AVF) presence (p = 0.02) and lower CRP (p = 0.003). Muscular cramps absence associated pruritus absence (p = 0.007) and AVF (p = 0.001). Absent pruritus patients were younger (p = 0.04), had higher Kt/V (p = 0.01) and more AVF (p = 0.02). Men insomnia was more severe in HD than HDF and albumin related (p = 0.007), while CRP was lower in absent pruritus. Women insomnia associated with muscular cramps (p = 0.04) and vascular access (p = 0.03), as was pruritus (p = 0.03). RT had no relations with any parameter. CONCLUSIONS: HD patients with AVF have less insomnia, muscular cramps and pruritus. Insomnia is associated with muscular cramps and inflammation. Pruritus is worse in older patients, is diminished with increased dialysis efficiency and is associated with higher CRP in men. There is no difference between HD and HDF patients, except more severe insomnia for HD in men.

Osteoprotegerin and uremic osteoporosis in chronic hemodialysis patients.

INTRODUCTION: Osteoprotegerin (OPG) is a powerful inhibitor of osteoclast activity, and it plays an important role in bone metabolism. In hemodialysis (HD) patients, the relationship between OPG and bone mineral density (BMD) is important, but remains unclear yet. The study objective was to assess the OPG role related to uremic osteoporosis in HD patients. METHODS: This cross-sectional study has been realized on a cohort of 63 chronic HD patients. INCLUSION CRITERIA: elderly prevalent HD patients with an age over 55 years old. EXCLUSION CRITERIA: previous bone disease or previous renal transplant; neoplasia; parathyroidectomy, hormone replacement therapy. The data regarding demographical and clinical characteristics, including treatments for mineral and cardiovascular complications, were recorded. Serum OPG and mineral markers levels were measured. BMD was assessed by calcaneus quantitative ultrasound; it measured broadband ultrasound attenuation, speed of sound (SOS) and stiffness index (STI). RESULTS: The high OPG levels were associated with higher bone mineral density (OPG-SOS P = 0.003; R = 0.37; OPG-STI P = 0.03; R = 0.28). Malnutrition, anemia and advanced age correlated with bone demineralization. Males had higher bone density parameters than females. In patients treated with vitamin D (P = 0.005), the BMD was increased comparing to patients without these treatments. CONCLUSIONS: OPG levels had directly correlated with bone mineral density parameters. Our study further confirms the critical role of OPG in the pathogenesis of uremic osteoporosis in ESRD. Whether the increased circulant OPG protect against bone loss in patients undergoing HD remains to be established.

Soluble CD40 ligand in haemodialysis patients: survival impact and cardiovascular prognostic role.

CONTEXT: Soluble CD40 ligand (sCD40l) can predict cardiovascular events (CVE) and mortality in haemodialysis (HD) patients (short-, medium-term follow-up studies). OBJECTIVE: To evaluate the relationship between sCD40l and survival, CVE and mortality in HD patients on long-term follow-up. METHODS: We registered 46 HD patients' baseline characteristics, mortality and CVE for 108 months. RESULTS: SCD40l correlated positively with C-reactive protein, was higher in survivors, but had no impact on survival and was not predictive for CVE or CV mortality. CONCLUSION: The levels of sCD40l have no influence on survival or CVE and mortality in HD patients in a long-term follow-up.

The metabolic hormone FGF21 is associated with endothelial dysfunction in hemodialysis patients.

PURPOSE: Finding new, reliable biomarkers of cardiovascular risk in hemodialysis (HD) patients is of utmost importance. Fibroblast growth factor 21 (FGF21) has been recently associated with atherosclerosis in the general population. The relationship between markedly elevated FGF21 levels in HD patients and endothelial dysfunction is unknown. The aim of the study was to assess the determinants of FGF21, the correlation between FGF21 and tumor necrosis factor TNF-like weak inducer of apoptosis (sTWEAK) and the correlation between FGF21 and endothelial dysfunction in HD patients. METHODS: A cross-sectional observational study was conducted in 70 HD patients (mean age 59.9 ± 12.5 years, 14.3% diabetes mellitus, 57.1% male) from Nefromed Dialysis Center Cluj. We registered clinical and biological data, and serum FGF21 levels were measured by ELISA. Endothelial function was evaluated by brachial flow-mediated dilation (FMD). An analysis based on stratification of FGF21 values into quartiles was performed. RESULTS: FGF21 levels were directly correlated with sTWEAK, tricipital skinfold thickness (TST), systolic blood pressure (SBP), total cholesterol and triglycerides. In multivariate linear analysis, only sTWEAK and SBP remained significantly associated with FGF21. FGF21 values in the inferior quartile were directly correlated with HDL-cholesterol, while FGF21 values in the superior quartile were directly correlated with SBP, pulse pressure and sTWEAK. FMD was significantly higher in the inferior quartile as compared to the superior quartile. CONCLUSIONS: High FGF21 values in our patients are correlated with atherosclerosis risk factors: hypercholesterolemia, hypertriglyceridemia, hypertension, increased TST and increased levels of sTWEAK. Endothelial dysfunction is associated with high FGF21 in HD patients.

Malondialdehyde can predict survival in hemodialysis patients.

BACKGROUND AND AIMS: Cardiovascular (CV) disease is the leading cause of morbidity and mortality in hemodialysis (HD) patients. Kidney disease is associated with increased oxidative stress (OS), a nontraditional CV risk factor. Few studies evaluate the effect of OS markers on CV events (CVE) and survival in HD patients. The aim of this study is to examine potential determinants of OS markers and their predictive role on survival and CV morbidity and mortality in HD patients during a long-term follow-up (108 months). METHODS: We conducted an analytical cross-sectional prospective observational study, carried on a cohort of randomly selected HD patients. We registered in 44 HD patients baseline characteristics, OS markers, mortality and CVE over a period of 108 months and we used statistical analysis (descriptive, Kaplan-Meier, univariate and multivariate Cox model) for interpretation. RESULTS: Bound malondialdehyde (bMDA) was positively correlated with serum calcium, protein carbonyls (PC) were inversely correlated with diastolic blood pressure (DBP) and directly correlated with ferritin, NOx was directly correlated with ceruloplasmin) and serum albumin. Of the measured OS markers only bMDA was related to survival (HR=3.29 95% CI (1.28-8.44), p=0.01), and approached statistical significance in the effect on CV mortality (HR=2.85 95% CI (0.88-9.22), p=0.07). None of the measured OS markers was associated with CVE. CONCLUSIONS: bMDA has a strong predictive value on survival in HD patients in a long-term follow-up (9 years). Its value is correlated with CV mortality but is not a predictor of CV events. Regular assessment of MDA in HD patients and the development of strategies aimed at reducing oxidative stress in these patients might be beneficial.

Nitroglycerin mediated dilation evaluated by ultrasound is associated with sTWEAK in hemodialysis patients.

AIMS: The main cause of death in hemodialysis (HD) patients is cardiovascular disease. Ultrasound assessment of the brachial artery dysfunction is easily achievable and can non-invasively detect atherosclerosis in various stages. In HD patients the cardiovascular risk profile is different and the determinants of brachial arterial function can be distinct comparing with general population. The aim of the study is to assess the determinants of arterial brachial function (flow-mediated and nitroglycerin-mediated dilation) evaluated by ultrasound in HD patients and their relation with tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) described as atherosclerotic marker in chronic kidney disease patients. MATERIAL AND METHODS: We conducted a cross-sectional observational study on 54 hemodialysis patients. We recorded clinical and biological data and we measured sTWEAK serum levels by ELISA. We evaluated the arterial brachial function by measurement of flow-mediated and nitroglycerin-mediated dilation, using B mode ultrasound. RESULTS: The determinants of flow-mediated dilation were: Kt/V (r=0.47, p<0.001), LDL-cholesterol (r=0.29, p=0.04), and total cholesterol (r=0.31, p=0.02). Flow-mediated dilation correlated with nitroglycerin-mediated dilation (r=0.70, p<0.001). In multivariate analysis kt/V was the only significant predictor for flow-mediated dilation (p=0.04). Nitroglycerin-mediated dilation correlates with sTWEAK (r=-0.30, p=0.03), systolic blood pressure (r=-0.28, p=0.04) and pulse pressure (r=-0.31, p=0.02). In multivariate analysis sTWEAK was the only significant predictor for nitroglycerin-mediated dilation (p=0.04). CONCLUSIONS: The main determinant of nitroglycerin-mediated dilation was sTWEAK. In addition, decreased nitroglycerin-mediated dilation was associated with higher systolic blood pressure and pulse pressure. The main determinant of FMD was Kt/V. Increased flow-mediated dilation was associated with better dialysis efficiency and high total cholesterol and LDL-cholesterol.

Mineral and bone disorders, morbidity and mortality in end-stage renal failure patients on chronic dialysis.

BACKGROUND AND AIM: In spite of numerous interventions, the control of mineral disturbances remains poor in end-stage renal failure (ESRF) patients. Chronic kidney disease - mineral and bone disorders (CKD-MBD) represent an important cause of mortality and morbidity. The aim of this study is to analyze the relationship between mineral and bone disorders (MBD) and their components impact on all-cause mortality and cardiovascular (CDV) mortality and morbidity in chronic dialysis patients. METHODS: This prospective study was carried out in a cohort of 92 randomly selected patients with ESRF treated with hemodialysis (HD) and peritoneal dialysis (PD). The data regarding demographic and clinical characteristics were recorded, including vascular disease (coronary, cerebral, peripheral). The follow-up lasted 40 months and the final evaluation included the number and causes of deaths, CDV events and disease. Serum Ca, P, ALP, iPTH, albumin, cholesterol, urea and creatinine levels were measured. The plain radiographic films of hands and pelvis evaluated all bone abnormalities suggestive of renal osteodystrophy (ROD) and peripheral vascular calcification (VC). RESULTS: All-cause annual mortality represented 9.25% in HD and 9.09% in PD patients. The CDV mortality represented almost 44% in HD patients and 66% in PD patients from all deaths. There was a high prevalence of CDV diseases and events. High and low serum P levels were associated with a worse survival rate. Hypercalcaemia was associated with high risk for CDV events in HD patients. In PD patients, the relationship between increased ALP levels and all-cause mortality was significant. Other mineral markers were not predictive of the outcome in the studied patients. In the HD patients the severity of VC was associated with all-cause and CDV mortality, and with CDV events. Male gender, hypercholesterolemia, decreased URR, albumin and creatinine were identified as risk factors for all-cause mortality. The diabetics had higher death rates. Low dialysis efficacy represented a risk factor for mortality and CDV diseases and events. In PD patients, low albumin induced a higher death rate. In PD patients the death rate was similar to HD patients. CONCLUSION: All-cause mortality was higher than in general population, but lower than the chronic dialysis patients' mortality reported in other studies. The death rates in HD and PD patients were similar. VC and serum P levels influenced the outcome in the HD patients - increased the risk for all-cause and CDV mortality, but also for CDV events. ALP levels influenced outcome in PD patients. There were no significant differences between HD and PD patients regarding outcome.

The association of high sCD163/sTWEAK ratio with cardiovascular disease in hemodialysis patients.

PURPOSE: Cardiovascular disease (CVD) is the most common cause of death in hemodialysis (HD) patients. Transmembrane proteins that circulate as soluble form such as tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) and CD163 have been proposed in previous studies as CVD biomarkers in chronic kidney disease patients. In HD patients, since studies are scarce, the role of these proteins is not completely understood. We tested the hypothesis that sTWEAK, sCD163 or sCD163/sTWEAK ratio could be associated with cardiovascular disease in HD patients. METHODS: We recorded current clinical and biological data, and we measured sTWEAK and sCD163 serum levels by ELISA in 70 hemodialysis patients. Univariate analysis and multivariate (logistic regression) analysis were used to identify the relation between sTWEAK, sCD163 and sCD163/sTWEAK ratio and CVD. RESULTS: In univariate analysis, CVD in HD patients is associated with higher sCD163/sTWEAK ratio (p = 0.04), sCD163 (p = 0.07), CRP (p = 0.04), age (p = 0.07), smoking (p = 0.09) and vascular calcifications (p = 0.10). In multivariate analysis, only logarithm of sCD163/sTWEAK ratio (p = 0.04) and smoking (p = 0.03) was significantly associated with CVD. The levels of these molecules and their ratio were correlated with atherosclerosis risk factors: diabetes mellitus, high fasting glucose, tricipital skinfold thickness and CRP as well as (for sCD163/sTWEAK) intravenous iron therapy. CONCLUSIONS: Cardiovascular disease is associated with increased sCD163/sTWEAK ratio. To our knowledge, this is the first report about this relationship in HD patients.

ESAM predicts cardiovascular mortality in diabetic hemodialysis patients.

AIM: To assess endothelial cell selective adhesion molecule (ESAM) as predictor of cardiovascular mortality in diabetic dialysis patients (DDPs). METHODS: ESAM, clinical and laboratory parameters were assessed in 73 DDP. Cardiovascular mortality was recorded in a 2 years' prospective observational study. RESULTS: Baseline ESAM was 17.1 (10.05-24.8) ng/ml and was correlated to phosphate (r = -0.42, p = 0.008), parathormone (r = -0.36, p = 0.048), albumin (r = -0.24, p = 0.048). ESAM significantly predicted cardiovascular death in univariate [HR = 1.03, 95% CI (1.006-1.054), p = 0.01] and multivariate [HR = 1.034, 95% CI (1.003-1.066), p = 0.03] Cox analysis. Time to cardiovascular death was shorter for patients with ESAM >12.44 ng/ml, p = 0.0045. CONCLUSION: ESAM is an independent predictor of cardiovascular mortality in DDP.

Survival after parathyroidectomy in chronic hemodialysis patients with severe secondary hyperparathyroidism.

INTRODUCTION: The life for end-stage renal disease patients has remarkably improved in the last years. Although mineral and bone disorders remain as unsolved complication, in severe secondary hyperparathyroidism (sHPT), the ultimate treatment is parathyroidectomy (PTX). It is an old treatment, but there are still insufficient data regarding survival after PTX. The study goals were to compare 2-year mortality and morbidity after PTX in surgically versus medically treated sHPT and to compare the efficacy and safety in subtotal versus total PTX in a cohort of patients receiving hemodialysis (HD). METHODS: This prospective, longitudinal study was carried out on a cohort of chronic HD patients with severe sHPT (iPTH over 700 pg/ml). Among the overall HD population, 26 patients underwent PTX. This group was compared to a control group treated with specific drugs. Laboratory parameters, specific symptoms and mortality were registered after 24 months of follow-up for each group. The subgroups of subtotal and total PTX patients were also compared. RESULTS: All average values of mineral markers were significantly reduced after PTX, as a proof that surgical treatment was effective. The reduction in mineral markers and the improvement in symptoms and mortality rates were similar after total and subtotal PTX. Bone pain was significantly lower in patients after PTX than in those drug treated (p = 0.0005), but not muscle weakness and itching. Survival at 2 years was better in patients surgically treated (PTX) despite significantly higher mean baseline values of iPTH, Ca and ALP compared to patients medically treated (p = 0.03). CONCLUSIONS: We compared clinical and laboratory outcomes in HD patients with severe sHPT. Mortality, bone pain and mineral markers were improved by PTX. Total and subtotal PTX had similar clinical outcomes.

ESAM predicts cardiovascular mortality in diabetic hemodialysis patients.

AIM: To assess endothelial cell selective adhesion molecule (ESAM) as predictor of cardiovascular mortality in diabetic dialysis patients (DDPs). METHODS: ESAM, clinical and laboratory parameters were assessed in 73 DDP. Cardiovascular mortality was recorded in a 2 years' prospective observational study. RESULTS: Baseline ESAM was 17.1 (10.05-24.8) ng/ml and was correlated to phosphate (r = -0.42, p = 0.008), parathormone (r = -0.36, p = 0.048), albumin (r = -0.24, p = 0.048). ESAM significantly predicted cardiovascular death in univariate [HR = 1.03, 95% CI (1.006-1.054), p = 0.01] and multivariate [HR = 1.034, 95% CI (1.003-1.066), p = 0.03] Cox analysis. Time to cardiovascular death was shorter for patients with ESAM >12.44 ng/ml, p = 0.0045. CONCLUSION: ESAM is an independent predictor of cardiovascular mortality in DDP.

Serum hyaluronic acid in chronic viral hepatitis B and C: a biomarker for assessing liver fibrosis in chronic hemodialysis patients.

PURPOSE: Serum hyaluronic acid (sHA) is studied as a noninvasive marker of liver fibrosis (F) in chronic B and C viral hepatitis in general population but less in end-stage renal disease patients undergoing hemodialysis. METHODS: We evaluated sHA as a noninvasive biomarker of F in a multicenter prospective, transversal, and observational study which included 52 end-stage renal disease patients with chronic B (14) and C (38) viral hepatitis (age 55.57 ± 14.46 years, dialysis vintage 132.59 ± 86.02 months). RESULTS: Of the noninvasive tests analyzed, only sHA, APRI, and FIB4 index were able to differentiate patients with F1 (sHA p = 0.006; APRI p = 0.031; FIB4 p = 0.016). No statistically significant differences were found between sHA and APRI, ASAT/ALAT ratio, and FIB4 index in detecting F1 a (p > 0.02). sHA seemed to be more efficient than APRI, ASAT/ALAT ratio, and FIB4 index, having the highest estimated AUC value. The sHA threshold value for F1 was equal to 33.46 ng/mL, with the following estimated values of the performance indicators: Se 88.46 % and Sp 50 %. sHA was the only noninvasive test of the studied tests that could determine F2 (p = 0.002), with a threshold value of 80.24 ng/mL (Se 63 %, Sp 88 %), and F3 (p = 0.008), with a threshold value of 88.54 ng/mL (Se 60 %, Sp 84 %). None of the studied noninvasive tests could determine F4. CONCLUSIONS: In patients with chronic B and C viral hepatitis undergoing hemodialysis, sHA may be a useful biomarker for the liver fibrosis grades: F1-mild, F2-moderate, and F3-severe, but it does not differentiate between chronic hepatitis (F1-F3) and liver cirrhosis (F4).

Role of osteoprotegerin in vascular disorders of the end-stage renal disease patients.

AIM: To assess the osteoprotegerin (OPG) relationship with cardiovascular complications in hemodialysis (HD) patients. METHODS: The study included 87 HD patients. Clinical characteristics, ankle-arm index (AAI), OPG and mineral markers levels were recorded. Arterial intimal calcification (AIC) and arterial medial calcification (AMC) were registered. RESULTS: OPG levels were increased in HD patients. Patients with AIC (p = 0.006)/ AMC (p = 0.01) had higher OPG levels. OPG did not have any relation with cardiovascular diseases. OPG correlated positively with age, increased HD vintage and inversely with albumin and AAI. OPG has not been a risk factor for VC or cardiovascular disease. CONCLUSION: OPG rising could be a reaction in defense to vascular aggression, because OPG was associated with VC, but not with vascular disease.

FGF-23, vascular calcification, and cardiovascular diseases in chronic hemodialysis patients.

INTRODUCTION: Chronic hemodialysis (HD) patients have bad prognosis and cardiovascular diseases (CVD) represent their main threatening complication. Fibroblast growth factor (FGF-23) has been associated with all kinds of evil consequences, including cardiovascular morbidity, but some studies demonstrated the contrary. Therefore, it is important to know whether FGF-23 is associated with cardiovascular risk or protection. The purpose of this study was to assess the links between FGF-23 and intimal vascular calcification (VC) and with the presence of CVD in chronic HD patients. PATIENTS AND METHODS: This study was carried out on a cohort of randomly selected 88 prevalent HD patients. We recorded demographical, clinical, and biochemical data, including FGF-23. VC was evaluated on carotid ultrasound. CVD were registered. RESULTS: The mean age was 59.68 ± 14.49 years, HD vintage was 59.61 ± 52.39 months, and 20 patients were diabetic (22.72 %). VC was present in 54 patients (61.4 %) and 25 patients (28.4 %) had CVD. FGF-23 correlated positively with HD vintage (r = 0.37; p < 0.001) and iPTH (r = 0.21; p = 0.048). FGF-23 did not correlate with VC score. Patients with CVD were older (p = 0.006), had lower FGF-23 (p = 0.008), higher VC score (p = 0.009), lower Hb (p = 0.008), albumin (p = 0.003), and creatinine (p = 0.03). Low FGF-23 was identified as a risk factor for CVD. CONCLUSION: We report on a novel association between low FGF23 and CVD in chronic HD patients and a lack of correlation of FGF-23 with VC. FGF-23 could play a role in cardiovascular protection that remains to be confirmed in larger studies.

Variation of clinical and laboratory features in chronic dialysis patients treated with high-flux hemodialysis after switching to online hemodiafiltration.

PURPOSE: The study of online hemodiafiltration (HDF) benefits over high-flux hemodialysis (HD) raises great interest. The purpose was to compare clinical and laboratory parameters in patients treated with HD who were switched to HDF. METHODS: Forty-eight HD patients (study group) were switched to HDF, while other 521 patients remained on HD as a control group. During last 6 HD months and during first year of HDF, we determined in both groups the following parameters: monthly-weekly dialysis time, systolic and diastolic blood pressure, body mass index (BMI), interdialytic body weight gain (IBWG), blood flow rate (Qb), weekly erythropoietin-stimulating agents dose (EPO), single-pool Kt/V, calcium, phosphorus (P), hemoglobin and normalized protein catabolic ration (nPCR), plus every 3 months--albumin, parathormone (PTH), ferritin and transferrin saturation (TSAT). In both groups, parameters in the last 6 HD months were compared to those in the first 6 months and, respectively, to those in the first year of HDF. RESULTS: In the study group, albumin and nPCR were significantly higher in the HD period not only compared to the first 6 months of HDF, but also compared to the first year of HDF. IBWG and P were higher with HD compared to the first year of HDF, but not with the first 6 months. PTH, Kt/V, Qb and EPO were higher in both HDF periods. In the control group, albumin was significantly higher in the first 6 months after the switch, but it was significantly lower in the first year. BMI, ferritin, PTH, Kt/V, Qb, TSAT and weekly dialysis time were higher in both HDF periods, while nPCR, EPO, SBP and DBP were lower. IBWG and Hb rose only during the first year after the switch, while P was lower in the first year, but not in the first 6 months. CONCLUSIONS: Nutrition, assessed by albumin, nPCR and BMI, was not improved by HDF compared to HD. With HDF, Kt/V and phosphorus control were better, similar results were observed in the control group. A larger EPO dose was needed with HDF for maintaining a similar hemoglobin level.