Publications (73)133.31 Total impact
- [Show abstract] [Hide abstract] ABSTRACT: INTRODUCTION AND AIMS: There is currently no consensus about the indications for therapeutic apheresis, also due to the lack of large clinical trials. A registry where all the data can be organized and analyzed therefore becomes a priority for all professionals involved in apheresis. METHODS: The Apheresis Study Group of the Italian Society of Nephrology has instituted a registry for data collection. This report describes data collected from 1994 to 2010 by 89 units of different specialties in 18/20 Italian regions. RESULTS: Data about 36,093 treatments on 3,097 patients were recorded. Plasma exchange accounted for 40.7% of the procedures; 34.3% of these were performed by filtration. Plasma treatment was used in 48.8% of procedures, in particular with protein A immunoadsorption (8.9%), LDL-cholesterol apheresis by dextran sulfate adsorption (13.9%), and semiselective cascade or double filtration (13.9%). Cell apheresis, limited to photopheresis and leukocytapheresis, was used in 4.9% of cases, and whole blood treatment, with different techniques, in 5.7% of cases for the treatment of dyslipidemia, liver failure and sepsis. These procedures account for about 20% of the estimated therapeutic apheresis performed in Italy according to the national survey performed for the year 2005 by the Italian Apheresis and Cell Manipulation Society. CONCLUSIONS: The data collected are sufficiently informative to show a definite trend to use plasma/whole blood treatments as often as possible. The registry not only is a tool for consultation and information, but also a platform to plan and realize interdisciplinary and multicenter clinical trials.
Article: Epidemiology & outcome in CKD 5D (1)[Show abstract] [Hide abstract] ABSTRACT: INTRODUCTION AND AIMS: Higher residential altitude has been associated with greater erythropoietin response and longer survival in ESRD patients. It has been hypothesized that persistent activation of hypoxia-inducible factors (HIF) at higher altitude may explain these associations. Animal models have shown that inactivation of prolyl-hydroxylases - regulators of HIF - suppresses mammary gland proliferation in vitro, with similar findings in lung, brain, and hematopoietic cancer lines. Thus, HIF activation may also affect cancer incidence in vivo. No studies have evaluated the association between altitude and cancer incidence. METHODS: We studied incident ESRD patients (1996-2006) who had no diagnosis of cancer prior to initiation of chronic dialysis. We required 2 medical claims with a cancer diagnosis (except for non-melanoma skin cancer) to define incident cancer. We also used previously validated algorithms to ascertain six specific malignancies: breast, lung, gastric, and colorectal cancer, leukemia and lymphoma. Patients were stratified by residential altitude (<250 ft./76 m.; 250-1999 ft./76-609 m., 2000-3999 ft./610-1218 m., 4000-5999 ft./1219-1828 m., ≥6000 ft./1829 m.). Cox regression was used to study the univariate and adjusted (for demographics, comorbidities, laboratories) associations among residential altitude and these incident cancer outcomes. RESULTS: The Medical Evidence Report forms of 928965 incident ESRD patients indicated no diagnosis of cancer and 118878 (12.8%) patients were found to have any cancer during follow up. Univariate analyses revealed a monotonic decrease in cancer incidence with higher altitude (p<0.001), which was only slightly attenuated after full adjustment. Compared with patients residing near sea level (<250 ft.), the adjusted relative risks of cancer decreased by 5% (95% CI: 3-6%), 9% (4-13%), 13% (8-19%), and 14% (1-24%) among patients living at 250-1999, 2000-3999, 4000-5999, and ≥6000 ft., respectively (see metric conversion above). Using only the six validated cancer algorithms above, the associations were even more pronounced. CONCLUSIONS: Higher residential altitude among ESRD patients was associated with lower cancer incidence despite adjustment for a large number of factors. While causality cannot be inferred from our study, our findings corroborate in vitro studies showing reduced cancer cell growth with prolyl-hydroxylase inhibition.
Article: Bone disease in CKD 5D[Show abstract] [Hide abstract] ABSTRACT: INTRODUCTION AND AIMS: Declining renal function is associated with a progressive increase in serum fibroblast growth factor-23 (FGF-23) levels. In patients on renal replacement therapy (RRT), high FGF-23 circulating levels have been associated with vascular calcifications and mortality, suggesting that FGF-23 could be a uremic toxin. In this perspective, reducing FGF-23 concentrations in this patient population appears an appealing approach. The purpose of our study was therefore to compare the clearance of FGF-23 between high flux haemodialysis (HD) and on-line haemodiafiltration (OL-HDF) procedures. METHODS: Two groups were defined according to their prevalent RRT modality. 53 patients (29 men, 24 women; median age 73 [range 41-91] years; mean dialysis vintage 4.4 [range 0.5-22.0] years) were included in the HD group while 32 patients (19 men, 13 women; median age 73 [range 40-89] years; mean dialysis vintage 3.5 [range 0.5-36.0] years) were included in the OL-HDF group. Serum pre- and post-dialysis FGF-23 levels were measured using a 2nd generation Human FGF-23 (C-Term) ELISA kit. Dialysis adequacy was assessed by serum urea and creatinine levels, urea single-pool Kt/V, and urea reduction rate. Bone and mineral disorders were evaluated by pre- and post-dialysis calcium and phosphate concentrations, calcium-phosphate product, intact parathyroid hormone (iPTH) and 25-hydroxyvitamin D3 levels. RESULTS: Median FGF-23 reduction rates were significantly higher with OL-HDF (55.7±25.2 %) versus HD (36.2±28.6 %) procedures (p=0.0331). Similarly, median calculated FGF-23 clearances (OL-HDF 55.0 vs. HD 41.8 ml/min, p = 0.015) and Kt/V (OL-HDF 1.00 vs. HD 0.72, p=0.0001) were significantly superior in the OL-HDF group. Overall, post-treatment FGF-23 levels were significantly lower than pre-treatment values in both RRT groups (p<0.01). Positive correlations between plasma FGF-23 levels and serum inorganic phosphate concentrations (R2=0.359; p<0.01), serum calcium-phosphate product (R2=0.410; p<0.01), and serum iPTH (R2=0.051; p<0.05) were observed. CONCLUSIONS: Our results demonstrate that FGF-23 levels are increased and positively correlated with serum phosphate, calcium-phosphate product and iPTH levels in ESRD patients on RRT. Additionally, we have shown that high flux HD using new generation polyether-sulfon filters could significantly remove FGF-23. However, OL-HDF, with its added convective clearance, achieves higher calculated FGF-23 reduction percentages, clearance values and Kt/V over high flux HD. Based on confirmed associations in ESRD patients between elevated FGF-23 levels on one hand and vascular calcifications and death on the other hand, better removal of this candidate uremic toxin thus represents a potential cardiovascular therapeutic avenue in this population.
- [Show abstract] [Hide abstract] ABSTRACT: Enhanced oxidative stress partly resulting from an over-production of superoxide anion (O(2)(•-)) represents a novel and particular risk factor in chronic kidney disease (CKD) patients. This study was therefore designed to evaluate O(2)(•-) determinants in this population. O(2)(•-) production was evaluated using chemiluminescence method in 136 CKD patients (79M/57F, median age: 69.5 [27.4-94.6]). Renal function (evaluated by the glomerular filtration rate using modification of diet in renal disease (MDRD)), inflammation, lipids, nutritional and bone mineral as well as clinical parameters were evaluated. Potential relationships between O(2)(•-) and these clinico-biological parameters were investigated to identify main determinants of such a pathological process. Enhanced O(2)(•-) production has been observed at the pre-dialysis phase: stages 4 and 5 of CKD (p = 0.0065). In multivariate analysis, low eGFR (MDRD <30 mL/min/1.73 m(2); p = 0.046), high fibrinogen (≥3.7 g/L; p = 0.044) and abnormal HDL cholesterol (<1.42 mmol/L and ≥ 1.75 mmol/L; p = 0.042) were the main determinants of O(2)(•-) production in CKD patients.
- [Show abstract] [Hide abstract] ABSTRACT: This prospective observational study aimed at evaluating efficacy and biocompatibility performances of the new heparin-coated Evodial dialyzers with/without systemic heparin reduction. After a 4-week wash-out period with reference polysulfone F70S dialyzers, 6 hemodialysis patients were sequentially dialyzed with Evodial, F70S, and Evodial dialyzers using 30% heparin reduction, each period of treatment was 4 weeks. Removal rates (RR) (urea, creatinine, and β2-microglobulin), dialysis dose, and instantaneous clearances (urea and creatinine) were measured as well as inflammatory (C-reactive protein, fibrinogen, interleukin 6, tumor necrosis factor α, and monocyte chemoattractant protein-1) and oxidative stress (OS) (superoxide anion, homocysteine, and isoprostanes) parameters at the end of each study period. Patients treated with Evodial or F70S dialyzers for 4 weeks presented comparable dialysis efficacy parameters including urea and creatinine RR, dialysis dose and instantaneous clearances. By contrast, a significantly lower but reasonably good β2-microglobulin RR was achieved with Evodial dialyzers. Regarding biocompatibility, no significant difference was observed with inflammation and OS except for postdialysis monocyte chemoattractant protein-1 which significantly decreased with Evodial dialyzers. Thirty percent heparinization reduction with Evodial dialyzers did not induce any change in inflammation but led to an improvement in OS as demonstrated by a decrease in postdialysis superoxide production and predialysis homocysteine and isoprostane. This bioactive dialyzer together with heparin dose reduction represents a good trade-off between efficacy and biocompatibility performance (improvement in OS with a weak decrease in efficacy) and its use is encouraging for hemodialysis patients not only in reducing OS but also in improving patient comorbid conditions due to lesser heparin side effects.
- [Show abstract] [Hide abstract] ABSTRACT: Whole-blood viscosity is increasingly being recognized as a factor implicated in the vascular disease progression in high-risk chronic kidney disease patients. Intermittent hemodialysis and hemodiafiltration sessions, characterized by rapid volume changes and anemia correction by erythropoietin stimulating agents, are favorable conditions for enhancing whole-blood viscosity changes and consequently triggering cardiovascular events. To evaluate whole-blood viscosity changes induced by hemodiafiltration, a cross-sectional study has been performed in a group of 28 stable patients. In order to assess the impact of vessel size on whole-blood viscosity changes, we performed a dynamic whole viscosity analysis on a wide spectrum of shear rates reproducing vasculature hemorheologic conditions. Blood viscosity changes are dependent on patient characteristics, hemoglobin, and total plasma protein concentrations. Whole blood viscosity increases significantly during hemodiafiltration over the complete spectrum of shear rates. Dynamic whole-blood viscosity (WBV) increases up to 60%, predominantly at low shear rates in small arterioles and capillary beds. This observation underlines the potential pathogenic contribution of WBV increase in capillaries triggering cardiovascular events in the postdialysis period. Eight patients died from cardiovascular events. Higher WBV increase was noted in this group but did not reach statistical significance due to the insufficient power of the study. Hemorheological changes associated with WBV increase in capillary beds may contribute to aggravate silent tissue hypoxemia and precipitate cardiovascular events in chronic kidney disease patients. Prospective studies specifically designed and powered to evaluate the impact of WBV changes on cardiovascular events in dialysis patients are required.
- [Show abstract] [Hide abstract] ABSTRACT: Expression of bone proteins resulting from transdifferentiation of vascular smooth muscle cells into osteoblasts suggests that vascular calcifications are a bioactive process. Osteoprotegerin (OPG) could play a key role in bone-vascular calcification imbalance and could be a marker of vascular calcification extent and progression. The purpose of this study was to evaluate relationships between vascular risk biomarkers (including classic risk factors and OPG) and coronary artery calcification (CAC) extent in chronic kidney disease (CKD) patients and to establish within the markers the appropriate cut-off value to predict CAC. A total of 133 non-dialyzed CKD patients at various stages of kidney disease [75 males/58 females, median age: 69.9 (27.4-94.6)] were enrolled, excluding extrarenal replacement therapy patients. All underwent chest multidetector computed tomography for CAC scoring. Blood samples were collected for measurement of vascular risk markers (kidney disease, inflammation, nutrition, calcium phosphate and OPG). A potential relationship between CAC and these biological markers was investigated, and a receiver-operating characteristic (ROC) curve was designed thereafter to identify a cut-off value of involved markers that best predicted the presence of CAC. After adjustment for age, diabetes, smoking and gender, among biological markers, only low-estimated glomerular filtration rate using Modification of Diet in Renal Disease [OR = 3.63 (1.10-12.02)], high FEPO(4) [OR = 3.99 (1.17-13.6)] and high OPG levels [OR = 8.54 (2.14-34.11)] were associated with the presence of CAC. A protective effect of 1.25(OH)(2) vitamin D [OR = 0.20 (0.05-0.79)] and LDL cholesterol [OR = 0.27 (0.08-0.94)] on CAC was also observed. ROC curve analysis showed that the OPG best cut-off value predicting CAC was 757.7 pg/mL. These results suggest that a CAC increase is strongly associated with a plasma OPG increase in CKD patients. The values of OPG >757.7 pg/mL allow us to predict the presence of CAC in these patients.
- [Show abstract] [Hide abstract] ABSTRACT: Infection constitutes a leading cause of morbidity and mortality in hemodialysis (HD) patients. The type of vascular access is an important determinant of the risk of infection. Therefore, identification of risk factors leading to catheter-related bacteremia (CRB) is strongly required. The aim of this prospective large cohort study of HD patients using only catheters as vascular access was to isolate risk factors for CRB. 2,230 permanent silicone dual catheters implanted in 1,749 patients between November 1982 and November 2005 were studied. The following data were collected at the time of catheter implantation: presence of hypertension, diabetes mellitus, obesity, atherosclerosis, immunodepression, Wright-Khan index, site and side of catheter insertion, and history of bacteremia. The site of catheter insertion was internal jugular (n = 2,133), subclavian (n = 79) and femoral (n = 17). Duration of catheter use was as follows: 30-90 days (n = 1,607) and >90 days (n = 1,054); 226 episodes of bacteremia occurred in 197 catheters. Microorganisms responsible were mainly Staphylococcus aureus, coagulase-negative staphylococci, Enterobacter spp. and Pseudomonas aeruginosa. The overall incidence of bacteremic episodes was 0.514/1,000 catheter days. Hypertension, atherosclerosis, diabetes mellitus, site of catheter implantation, duration of catheter use, Wright-Khan comorbidity index and previous history of CRB were significant risk factors associated with bacteremia in univariate analysis. Multivariate analysis revealed that a previous history of a bacteremic episode (odds ratio, OR = 2.70, 95% confidence interval, CI = 1.56-4.68), diabetes mellitus (OR = 2.37, 95% CI = 1.65-3.39), duration of catheter use >90 days (OR = 1.85, 95% CI = 1.35-2.55) and hypertension (OR = 1.49, 95% CI = 1.08-2.04) were still significant factors associated with bacteremia. Reducing CRB is still a challenge for nephrologists to reduce patient morbidity and mortality. Our study could demonstrate that diabetes, previous history of CRB, site of catheter implantation and duration of catheter use were the most important risk factors for bacteremia. Therefore, to prevent CRB, particular attention should be paid to patients with diabetes and a previous history of bacteremia following strict hygienic and aseptic rules for catheter handling associated with the regular use of antiseptic lock solutions.
- [Show abstract] [Hide abstract] ABSTRACT: Oxidative stress is commonly observed in chronic renal failure patients resulting from an unbalance between overproduction of reactive oxygen species and impairement of defense mechanisms. Proteins appear as potential targets of uremia-induced oxidative stress and may undergo qualitative modifications. Proteins could be directly modified by reactive oxygen species which leads to amino acid oxydation and cross-linking. Proteins could be indirectly modified by reactive carbonyl compounds produced by glycoxidation and lipo-peroxidation. The resulting post-traductional modifications are known as carbonyl stress. In addition, thiols could be oxidized or could react with homocystein leading to homocysteinylation. Finally, tyrosin could be oxidized by myeloperoxidase leading to advanced oxidative protein products (AOPP). Oxidatively modified proteins are increased in chronic renal failure patients and may contribute to exacerbate the oxidative stress/inflammation syndrome. They have been involved in long term complications of uremia such as amyloidosis and accelerated atherosclerosis.
- [Show abstract] [Hide abstract] ABSTRACT: Vascular calcifications constitute an important risk factor for mortality in chronic kidney disease patients. A better knowledge of physiopathologic phenomena responsible for vascular mineralization leads to emerging biological markers of vascular calcifications. In calcified arteries, presence of bone matrix as well as osteoblast cells suggest that vascular calcification is an active and highly regulated process. In uremic environment, vascular smooth muscle cells can transdifferentiate into osteoblast-like cells. The OPG–RANK–RANKL system is clearly of central significance in controlling vascular calcifications as in bone metabolism. Converging results suggest that circulating OPG determination should be a relevant marker of calcifications. Impairment in inhibitory system such as Matrix Gla Protein and fetuin-A promotes bone matrix calcification. Finally, FGF-23, an early and sensitive marker of bone and mineral disorders in chronic kidney disease patients, appears as a promising marker.
- [Show abstract] [Hide abstract] ABSTRACT: Oxidative stress is commonly observed in the elderly and could be involved in age-related diseases. However, the determinants of superoxide anion overproduction are not clearly understood. Superoxide anion production was evaluated using a lucigenin-based chemiluminescence method in 478 elderly subjects (304 women, 174 men; 79.5+/-7.1 years). Homocysteine (HCy) metabolism (homocysteinemia, vitamin B12, plasma, and erythrocyte folates), inflammation (CRP, fibrinogen, alpha-1 acid glycoprotein), lipid parameters (total cholesterol, triglycerides, HDL and LDL cholesterol), and nutritional parameters (albumin, transthyretin) were determined. The results show that HCy levels (p<0.001) and superoxide anion production (p=0.04) increase with aging, but CRP does not. Highest HCy (>20 microM) (OR 1.83 (1.09-3.07), p=0.02) and CRP over 5 mg/L (adjusted OR 2.01 (1.15-3.51), p=0.01) are the main determinants in superoxide anion production in the elderly. These clinical data are confirmed in an in vitro study using THP-1 monocyte-like cells. Incubation with HCy thiolactone (HTL) (0-200 microM) and LPS (0-20 ng/ml) dramatically enhances NADPH oxidase expression and activation. Moreover, a synergic action was evidenced for low concentrations of HTL (20 microM) and LPS (5 ng). Taken together, the clinical data and in vitro experiments support the hypothesis that moderate homocysteinemia and low-grade inflammation synergically enhance NADPH oxidase activity in the elderly.
- [Show abstract] [Hide abstract] ABSTRACT: Recent studies showed that hydrogen peroxide (H(2)O(2)) enhanced bone markers expression in vascular smooth muscle cells (VSMCs) implicated in osteoblastic differentiation. This study aimed at investigating the role of NAD(P)H oxidase in vascular calcification processes. A7r5 rat VSMCs were incubated with beta-glycerophosphate (10 mm) or uremic serum to induce a diffuse mineralization. H(2)O(2) production by VSMCs was determinated by chemiluminescence. NAD(P)H oxidase sub-unit (p22(phox)), Cbfa-1, ERK phosphorylation and bone alkaline phosphatase (ALP) expressions were measured by Western blotting. VSMCs exhibited higher production of H(2)O(2) and early expression of p22(phox) with beta-glycerophosphate or uremic serum within 24 h of treatment. beta-glycerophosphate-induced oxidative stress was associated with Cbfa-1 expression followed by ALP expression and activity, meanwhile the VSMCs expressing ALP diffusely calcified their extracellular matrix. Interestingly, diphenyleneiodonium partly prevented the osteoblastic differentiation. Results from this model strongly suggest a major implication of vascular NAD(P)H oxidase in vascular calcification supported by VSMCs osteoblastic differentiation.
- [Show abstract] [Hide abstract] ABSTRACT: Inflammation-induced atherosclerosis and enhanced susceptibility to infection are linked to immune dysfunction and account for an important part of mortality in hemodialysis patients. This 4-yr prospective study aimed to use cytokine proteomic determination for predicting cardiovascular and noncardiovascular mortality in hemodialysis patients. Levels of 12 cytokines were measured using a proteomic biochip system in 134 patients who were on stable hemodialysis and compared with a control group of 150 healthy volunteers. Cox proportional hazards regression analysis was used to determine the relationship between cytokine and clinical outcome. A proinflammatory state characterized by decreased anti-/proinflammatory cytokine ratio was evidenced in hemodialysis patients compared with control subjects. After adjustment for age, gender, smoking, and high-sensitivity C-reactive protein levels, IL-6 and (IL-4+IL-10)/IL-6 ratio were associated with a significant and specific enhanced hazard ratio of cardiovascular mortality (hazard ratio 11.32 [95% confidence interval 2.52 to 50.90; P < 0.01] and hazard ratio 3.14 [95% confidence interval 1.20 to 8.22; P < 0.05], respectively, when comparing the third and first tertiles). It is interesting that (IL-4+IL-6+IL-10)/(IL-2+IFN-gamma) ratio, used as a marker of lymphocytes T helper subsets cytokine secretion, was associated only with noncardiovascular mortality (hazard ratio 4.93; 95% confidence interval 1.03 to 23.65; P < 0.05). Beyond the strong prediction of cardiovascular mortality by IL-6, determination of cytokine ratios can be useful to identify hemodialysis patients with increased noncardiovascular mortality risk.
- [Show abstract] [Hide abstract] ABSTRACT: This study aimed at evaluating oxidative stress (OS) markers (i) in a cross-sectional study of hemodialysis (HD) patients to investigate potential regional effects of these markers and (ii) in a prospective crossover study to evaluate vitamin E-coated membrane (VE) effects. At baseline, OS parameters including low-density lipoprotein (LDL) oxidizability were measured in HD patients from five dialysis facilities. Patients were then randomly assigned to two treatment groups: group I patients (n = 33) switching to VE, and group II patients (n = 29) still using reference polysulfone (PS) membrane. After 3 months, patients were switched from VE to PS and vice versa for 6 months. The same OS parameters were measured after each period. At baseline, the cross-sectional analysis of LDL oxidizability showed a regional effect. By contrast, the crossover study did not show beneficial effects of VE on this parameter. Regional variations of LDL oxidizability in HD patients exist and may explain discrepancies in interventional therapy on OS.
- [Show abstract] [Hide abstract] ABSTRACT: Malnutrition and inflammation are recognized as important predictors of poor clinical outcome in haemodialysis (HD). This study was designed to estimate the relative contribution of known biological markers of inflammation, malnutrition and muscle mass in the prognosis of HD patients. A total of 187 HD patients (100 women, 87 men, median age 66.7 years [22.3-93.5]) were followed-up yearly for 5 years. At baseline, pre-dialysis values of C-reactive protein (CRP), albumin, transthyretin, total HDL- and LDL-cholesterol and triacylglycerol were determined. Estimation of creatinine index (CI) as muscle mass marker was determined by creatinine kinetic modelling using pre- and post-dialysis creatinine values. During the follow-up period, 89 deaths (53 from cardiovascular causes) were observed. After adjustment for age, gender, dialysis vintage, smoking, diabetes mellitus and hypertension, the highest tertile of CRP and lowest tertile of transthyretin and CI were significantly associated with all-cause mortality (relative risk (RR)=1.98 [1.12-3.47], 2.58 [1.48-4.50], 2.71 [1.42-5.19], respectively). In addition, low CI had an additive value to low levels of transthyretin. In contrast, high cholesterol (RR=0.47 [0.27-0.83], P=0.0091) and vitamin E concentrations (RR=0.46 [0.26-0.80], P= 0.006) showed a protective trend for all-cause mortality. In the multivariate analysis, transthyretin appeared as the most predictive biological marker of non-CV mortality (RR=3.78 [1.30-10.96], P=0.014), and CI of CV mortality (RR=2.61 [1.06-6.46], P=0.038), respectively. Discussion. These results confirm that uraemic malnutrition constitutes an important risk factor for mortality in HD. Beyond transthyretin, CI seems to be an additional marker routinely available and monthly determined in HD patients.
- [Show abstract] [Hide abstract] ABSTRACT: Patients undergoing maintenance hemodialysis (HD) have a high prevalence of protein-energy malnutrition and inflammation. As these 2 conditions often occur concomitantly in HD patients, they have been referred to together as the ‘malnutrition-inflammation complex syndrome’ (MICS) or ‘malnutrition-inflammation atherosclerosis’ (MIA) syndrome to emphasize its important association with atherosclerotic cardiovascular disease. Oxidative stress, which results from an imbalance between oxidants and antioxidant defense mechanisms, is well established in HD subjects and could contribute to the poor clinical outcome of these patients. The aim of the present review is to discuss in more detail the common consequences of MICS and oxidative stress and their possible relationships with the long-term complications of HD patients, leading to the conclusion that a complex syndrome similar to the MICS or MIA is the oxidative stress-inflammation association, which may be called the “oxidative stress complex syndrome.”
- [Show abstract] [Hide abstract] ABSTRACT: beta(2)M is a strong and independent indicator of hemodialysis patient outcomes and an excellent surrogate for middle molecules, and deserves to be routinely monitored and incorporated into dialysis adequacy targets. beta(2)M has a double meaning, reflecting both dialysis efficacy in terms of solute mass transfer and patient bioactivity. The work of Ward et al. in this issue warrants a study to test the hypothesis that long daily hemodiafiltration treatment would be the optimal renal replacement modality to improve dialysis patient outcomes.
- [Show abstract] [Hide abstract] ABSTRACT: Thrombosis of arteriovenous fistula (AVF) is the leading cause of vascular access (VA) loss usually due to silent stenosis. Therefore, assessment of relevant risk factors of VA monitoring may provide insight into potential therapeutic targets for stenosis and thrombosis. The aim of this study was to evaluate the influence of cardiovascular risk factors (including inflammation and mineral metabolism dysfunctions) on the failure of internal AVF in HD patients. 128 HD patients with internal AVF were included in the study and followed up for two years. At baseline, VA morphology and function were followed by Doppler ultrasonography and serum albumin, prealbumine, C-reactive protein, orosomucoid, calcium, phosphorus, parathyroid hormone, bone-type alkaline phosphatase, osteoprotegerin and receptor activator of nuclear factor ê ê B ligand were measured. At baseline, 50 stenoses were detected but none of them required any intervention. Age and biological parameters did not significantly differ between patients with or without VA stenosis. Over the two year- follow up, VA thrombosis occurred in 19 patients. Preexisting stenosis of VA was present in 9/19 patients (47.3% of cases) (chi-square = 3.708, p = 0.0538). Despite the low rate of events, phosphorus [1.75 (0.95-2.77) vs 1.42 (0.47-3.22) mmol/L, p = 0.0416], Calcium x Phosphorus product [4.00 (2.00-5.90) vs 3.40 (1.10-6.80) mmol(2)/L(2), p = 0.0676] and parathyroid hormone [165.00 (1.00-944.00) vs 79.50 (1.00-846.60) ng/L, p = 0.0814) levels were higher in the 19 thrombotic patients whereas all other biological parameters did not significantly differ. These results, which confirm that VA thrombosis occurs more frequently upon preexisting stenosis, also demonstrate that mineral metabolism disorders, compared to inflammation, may contribute to VA dysfunction leading to thrombosis.
- [Show abstract] [Hide abstract] ABSTRACT: Despite several technical advances in dialysis treatment modalities and a better patient care management including correction of anemia, suppression of secondary hyperparathyroidism, lipid and oxidative stress profiles improvement, the morbidity and the mortality of dialysis patients still remain still elevated. Recent prospective interventional trials in hemodialysis (HEMO study and 4D study) were not very conclusive in showing any significant improvement in dialysis patient outcomes. High-efficiency convective therapies, such as online hemodiafiltration (HDF), are claimed to be superior to conventional diffusive hemodialysis (HD) in improving the dialysis efficacy and in reducing intradialytic morbidity and all-cause and cardiovascular mortality in dialysis patients. The aim of this report was, first, to review the evidence-based facts tending to prove the superiority of HDF vs. HD in terms of efficacy and tolerance, and, second, to analyze the needs to prove the clinical superiority of HDF in terms of reducing morbidity and all-cause mortality of dialysis patients. A systematic review of studies comparing HDF and HD has been performed in the microbiological safety of online production, the solute removal capacity of small and medium-size uremic toxins, and its implication in the reduction of the bioactive dialysis system vs. patient interaction. Major planned randomized international studies comparing HDF and HD in terms of morbidity and mortality have been reviewed. To conclude, it is thought that these long-term prospective randomized trials will clarify on a scientific evidence-based level the putative beneficial role of high-efficiency HDF modalities on dialysis patient outcomes.
French National Centre for Scientific ResearchLutetia Parisorum, Île-de-France, France
Université de MontpellierMontpelhièr, Languedoc-Roussillon, France