Long-term effects of citric acid-based bicarbonate haemodialysis on patient outcomes: a survival propensity score-matched study in western France.

BACKGROUND: Citric acid-based bicarbonate haemodialysis (CIT-HD) has gained more clinical acceptance over the last few years in France and is a substitute for other acidifiers [e.g. acetic acid (CH3COOH) and hydrochloric acid (HCl)]. This trend was justified by several clinical benefits compared with CH3COOH as well as the desire to avoid the consequences of the corrosive action of HCl, but a nationwide clinical report raised concerns about the long-term safety of CIT-HD. The aim of this study was to assess the long-term effects of CIT-HD exposure on patient outcomes in western France. METHODS: This is a population-based retrospective multicentre observational study performed in 1132 incident end-stage kidney disease patients in five sanitary territories in western France who started their renal replacement therapy after 1 January 2008 and followed up through 15 October 2018. Relevant data, collected prospectively with the same medical software, were anonymously aggregated for the purposes of the study. The primary goal of this study was to investigate the effects of citrate exposure on all-cause mortality. To provide a control group to CIT-HD one, propensity score matching (PSM) at 2:1 was performed in two steps: the first analysis was intended to be exploratory, comparing patients who received citrate ≤80% of the time (CIT-HD ≤80) versus those who received citrate >80% of the time (CIT-HD >80), while the second analysis was intended to be explanatory in comparing patients with 0% (CIT-HD0) versus 100% citrate time exposure (CIT-HD100). RESULTS: After PSM, in the exploratory part of the analysis, 432 CIT-HD ≤80 patients were compared with 216 CIT-HD >80 patients and no difference was found for all-cause mortality using the Kaplan-Meier model (log-rank 0.97), univariate Cox regression analysis {hazard ratio [HR] 1.01 [95% confidence interval (CI) 0.71-1.40]} and multivariate Cox regression analysis [HR 1.11 (95% CI 0.76-1.61)] when adjusted for nine variables with clinical pertinence and high statistical relevance in the univariate analysis. In the explanatory part of the analysis, 316 CIT-HD0 patients were then compared with 158 CIT-HD100 patients and no difference was found using the Kaplan-Meier model (log-rank 0.06), univariate Cox regression analysis [HR 0.69 (95% CI 0.47-1.03)] and multivariate Cox regression analysis [HR 0.87 (95% CI 0.57-1.33)] when adjusted for seven variables with clinical pertinence and high statistical relevance in the univariate analysis. CONCLUSIONS: Findings of this study support the notion that CIT-HD exposure ≤6 years has no significant effect on all-cause mortality in HD patients. This finding remains true for patients receiving high-volume online haemodiafiltration, a modality most frequently prescribed in this cohort.

Hemodialysis in satellite dialysis units: incidence of patient fallback to the in-center dialysis unit.

BACKGROUND: Patient fallbacks occur when a patient treated in a satellite dialysis unit (SDU) must be transferred to an in-center dialysis unit. Fallbacks have an impact on the in-center dialysis unit organization. This study was carried out to estimate the incidence and risk factors of patient fallback. METHODS: Between 01/01/2006 and 31/12/2010 there were 193 patients starting dialysis in SDUs in one French region. The primary outcome was the incidence of temporary and permanent fallbacks with or without hospitalization. A survival analysis and binomial negative regression were used for the statistical analysis. RESULTS: Among the 193 patients, 117 (60.6%; 95% confidence interval [CI]: 53.3-67.6) had at least one fallback, which occurred within a median of 249 days (interquartile range [IQR]: 71-469) after the first session in the SDU. The median number of fallbacks by subject was 1 (IQR: 0-4). The median duration of the fallback period was 4 days (IQR: 1-8) and median number of dialysis sessions during the fallback time was 1 (IQR: 1-3). Of the 494 temporary fallbacks, 210 were due to patient hospitalization, the main cause of which was cardiovascular disease. At univariate analysis, patients permanently transferred to in-center hemodialysis units were older, had more peripheral arteriopathy, cancer and arrhythmia. At multivariate analysis, peripheral arteriopathy (relative risk [RR] 2.06, 95% CI 1.05-4.09) and the center (center 2: RR 0.42, 95% CI 0.21-0.84; center 3: RR 2.88, 95% CI 1.20-6.91) were significantly associated with the number of fallbacks. CONCLUSION: Fallback is a common event in hemodialysis patients treated in SDUs. Yet, the SDU system operates well since a third of patients treated in these units are still in SDUs at 2 years of follow-up. Factors associated with patient fallback are the center and cardiovascular disease.

[Extracellular hydration status and residual urinary sodium excretion in chronic hemodialysis patients: a cross-sectional multicenter study]. / Statut d'hydratation extracellulaire et natriurèse résiduelle en hémodialyse chronique : une étude transversale multicentrique.

BACKGROUND: In dialysis patients, a misevaluation of dry weight may lead to an increased morbidity and mortality. The aim of this cross-sectional multicenter study was to evaluate the association between residual urinary sodium excretion and extracellular volume status in chronically treated hemodialysis patients. PATIENTS AND METHODS: Dry weight was determined clinically and by whole-body bioimpedance spectroscopy (Body Composition Monitor, Fresenius Medical Care) prior to a mid-week session in 40 chronic hemodialysis patients with significant residual diuresis (more than 250 mL per day) and receiving treatment in four dialysis centers. Regarding their hydration status assessed by the Body Composition Monitor and in comparison to a healthy reference population, patients were assigned to 1 of the 3 categories: overhydrated, normohydrated and dehydrated. Urine output, urinary sodium excretion and residual renal function were measured for all patients within 30 days before dry weight assessment. RESULTS: The median post-HD session FO was of-0.40 L (IQR: from-1.95 to+0.90) and the median residual urinary sodium excretion was of 64 mmol/L (IQR: 46-79). Among these patients, 16 were normohydated, 16 were dehydrated and 8 were overhydrated. There was a linear relationship between the hydration status after HD session and the urinary sodium excretion (estimate: 5.6±1.5; p<0.001). Compared with normohydrated patients, overhydrated patients had a higher residual urinary sodium excretion (estimate: 26±10; p<0.01). CONCLUSION: In this study, urinary sodium excretion is associated with the hydration status evaluated by whole-body bioimpedance spectroscopy.

[Who is the physician in charge with the primary care of the dialysis patients?]. / Qui est le médecin de soins primaires du patient traité par hémodialyse ?

INTRODUCTION: The role played by nephrologists in hemodialysis patients' primary care is not well known. We hypothesized that primary care are provided by nephrologists and not by general practitioners for most of these patients. The aim of this study was to estimate the rate of hemodialysis patients having a nephrologist as primary care provider, and to determine which factors were associated with non-resort to a general practitioner for primary care. METHODS: Patients older than 18 years treated by hemodialysis for more than 3 months in the Calvados district were included and were interviewed with a standardized questionnaire. A log-binomial regression was used to study factors associated with non-resort to a general practitioner for primary care. RESULTS: Only 26% of patients had a general practitioner involved in the primary care; whereas 47% considered that nephrologists were the physician in charge of the primary care. Time spent in hemodialysis was associated with non-resort to a general practitioner, while patients living in nursing home were more likely to have regularly a regular follow up by a general practitioner. Dialysis center was a factor associated with the general practitioner as a primary care provider. CONCLUSION: Primary care of the hemodialysis patient is provided by nephrologists.

The identification of MAFB mutations in eight patients with multicentric carpo-tarsal osteolysis supports genetic homogeneity but clinical variability.

Multicentric carpo-tarsal osteolysis (MCTO) with or without nephropathy is a rare osteolysis disorder beginning in early childhood and involving mainly carpal and tarsal bones. Renal disease appears later in life in the majority of cases and evolves quickly to end stage renal failure. Autosomal dominant (AD) inheritance has been demonstrated, with a high frequency of sporadic cases. Recently, mutations in a highly conserved region of the MAFB gene (v-maf musculoaponeurotic fibrosarcoma oncogene ortholog B) have been identified in MCTO patients by exome sequencing. MafB, known as a regulator of various developmental processes, is essential for osteoclastogenesis and renal development. We report here the molecular screening of MAFB in eight MCTO patients from six families. We identified MAFB mutations in all, including three novel missense mutations clustering within the hot spot mutation region. Among the eight patients, six only presented renal disease. Our report confirms the genetic homogeneity of MCTO and provides data underlying the clinical variability of this disorder.

Is transition between peritoneal dialysis and hemodialysis really a gradual process?

BACKGROUND: Transfer to hemodialysis (HD) is a frequent cause of peritoneal dialysis (PD) cessation. In the present study, we set out to describe the transition period between PD and HD. METHODS: All patients in 4 centers of Basse-Normandie who had been treated with PD for more than 90 days and who were permanently transferred to HD between 1 January 2005 and 31 December 2009 were retrospectively reviewed. The rate of unplanned HD start was evaluated. RESULTS: In the 60 patients (39 men, 21 women) included in the study, median score on the Charlson comorbidity index at PD initiation was 5 [interquartile range (IQR): 3 - 7], median age at HD initiation was 62 years (IQR: 54 - 76 years), and median duration on PD was 22 months (IQR: 12 - 36 months). Among the 60 patients, 37 had an unplanned HD initiation. Peritonitis was the most frequent cause of unplanned HD start (n = 20), and dialysis inadequacy (n = 11), the main cause of planned HD start. During the transition period, all patients were hospitalized. Median duration of hospitalization was 4.5 days (IQR: 0 - 25.5 days). Within 2 months after HD initiation, 9 patients died. Two months after starting HD, 6 of the remaining 51 patients were being treated in a self-care HD unit and only 23 patients had a mature fistula. CONCLUSIONS: Unplanned HD start is a common problem in patients transferred from PD. Further studies are needed to improve the rate of planned HD start in PD patients transferred to HD.

Treatment strategies and outcome of induction-refractory Wegener's granulomatosis or microscopic polyangiitis: analysis of 32 patients with first-line induction-refractory disease in the WEGENT trial.

OBJECTIVES: To study the efficacy of rescue treatment strategies and outcomes in patients with Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA) not achieving remission with first-line induction with corticosteroids (CS) and intravenous cyclophosphamide (CYC). METHODS: 159 eligible patients in the Wegener's Granulomatosis-Entretien (WEGENT) trial newly diagnosed with systemic or renal WG or MPA with ≥ 1 poor prognosis factors were included in this prospective study. Rescue treatment strategies and outcomes in patients with induction-refractory disease were analysed and patient characteristics at diagnosis were compared with those of induction-responders. RESULTS: Most patients (n=126, 79.2%) achieved remission; 1 stopped induction because of allergy and 32 were induction-refractory (24 WG and 8 MPA); 11 died rapidly within a median of 2.5 months, 6 of uncontrolled disease, 1 of an infectious complication and 4 of both. Treatment was discontinued in 1 patient with MPA with end-stage renal disease. Induction was switched to oral CYC in 20 patients, combined with infliximab in 1; 15 (75%) achieved remission or low disease activity state, 3 subsequently died of uncontrolled disease and 2 entered remission using several other agents including biological agents. Alveolar haemorrhage and a creatinine level >200 µmol/l were independently associated with induction-refractory disease. Among patients with induction-refractory disease, massive alveolar haemorrhage was associated with higher mortality. CONCLUSION: Switching to oral CYC can be an effective rescue treatment for patients with systemic forms of WG or MPA who fail to achieve remission with first-line CS and intravenous CYC. However, a more rapidly effective regimen remains to be identified for most severely affected patients whose outcomes can be rapidly fatal.

[Transfer from chronic haemodialysis to peritoneal dialysis]. / Transfert en dialyse péritonéale après traitement par hémodialyse chronique.

Peritoneal dialysis patients are frequently transferred from peritoneal dialysis to haemodialysis. In contrary transfer from chronic haemodialysis to peritoneal dialysis is rare. The aim of this study is to describe the main characteristics and the outcome of the dialysis patients transferred from haemodialysis to peritoneal dialysis. We retrospectively analyzed the files of 25 patients treated by haemodialysis for more than 3 months between 1992 and 2002 and subsequently transferred on peritoneal dialysis. Technique survival was 56% at 1 year and 40% at two years in haemodialysis. Technique survival was lower in the group starting haemodialysis in emergency compared with the group of patients who did not need emergent haemodialysis (33 vs 77% at 1 year, P<0.05). The reasons for transfer from haemodialysis to peritoneal were vascular access problems (13/25), cardiovascular problems (7/25), and patient's choice (5/25). Automated peritoneal dialysis was used in 9 cases and continuous ambulatory peritoneal dialysis in 16 cases. In 13 cases peritoneal dialysis was performed by a home care nurse. At the initiation of peritoneal dialysis the mean age was 58+/-18 years, the mean Charlson's comorbidity score was 6.1+/-2.5 and 15 patients had a cardiovascular disease. The median time on peritoneal dialysis was 5.2 months. During the time on peritoneal dialysis sixteen patients presented at least one complication related to peritoneal dialysis. In addition fourteen patients were hospitalized for a reason which was not associated with peritoneal dialysis. Survival on peritoneal dialysis was 61% at six months and 35% at one year. In conclusion, in our study, patients transferred from haemodialysis to peritoneal dialysis have had a poor outcome on peritoneal dialysis. However, these patients presented numerous comorbid conditions at peritoneal dialysis initiation which could explain the poor outcome on peritoneal dialysis.