The Decline in Residual Renal Function in Hemodialysis Is Slow and Age Dependent

Background: Persons on peritoneal dialysis and hemodialysis with preserved residual renal function experience lower mortality rates than those without. Previous studies have shown slower rates of decline of residual renal function for peritoneal dialysis (PD)(2 to 3% decrease/month), compared with hemodialysis (HD)(6 to 7% decrease/month). However, our clinical observations suggested a lower rate of decline in hemodialysis patients. Methods: We evaluated data in 174 hemodialysis patients cared for from January 2000 through October 2001. Eighty‐seven (50%) patients had at least two timed quarterly urine collections to estimate the rate of change of residual renal function over time (urea clearance, or KrU). All patients underwent thrice‐weekly hemodialysis using polysulfone dialyzers with formaldehyde reprocessing. The rate of decline of residual renal function and the effect of KrU on laboratory variables were estimated using a random effects (MIXED) model, adjusting for the effects of age, sex, race, diabetes, and dialysis vintage. Results: The mean KrU at baseline was 3.5 mL/min. Men (P < 0.001) and persons of shorter vintage (P < 0.0001) had more residual renal function at baseline. The estimated rate of decline of residual renal function was ? 0.07 mL/min/month (? 1.9% decrease/month). The rate of decline in residual renal function was unaffected by sex, race, diabetes, or vintage, although the rate of decline was significantly attenuated among older individuals (age x time interaction, P = 0.01). Serum phosphorus (P = 0.03) and the calcium x phosphorus product (P = 0.009) increased over time and were influenced by the level of residual renal function (P = 0.06 and P = 0.006, respectively). Residual renal function did not influence the rate of change of other laboratory variables. Conclusions: In an ethnically diverse cohort of hemodialysis patients, the rate of decline of residual renal function was relatively slow and age dependent, as well as consistent with values others have reported for patients on peritoneal dialysis. Universal use of biocompatible dialyzers and bicarbonate dialysate may have contributed to differences discussed in prior reports. Residual renal function attenuated the increase in calcium–phosphorus product over time. A better understanding of the determinants of the rate of decline in residual renal function, and the specific benefits afforded to patients via maintenance of residual renal function, would help to inform the debates on timing of initiation and various dosing strategies in hemodialysis.     

Occult hepatitis B among patients with chronic renal failure on hemodialysis from a capital city in northeast Brazil

Occult hepatitis B (OHB) is characterized by the presence of HBV‐DNA in the absence of HBsAg in the serum of patients. Hemodialysis patients are at high risk for hepatitis B virus and there are few data on the prevalence of OHB in this population, mainly in Brazil. Thus, the aim of this study was to determine the prevalence of OHB in patients undergoing hemodialysis. A cross‐sectional study was performed, including 301 patients on chronic hemodialysis at two dialysis centers in São Luís (Maranhão), northeast Brazil. Serological tests were performed for HBsAg, anti‐HBc, anti‐HBs, and anti‐HCV using enzyme immunoassays (ELISA); HBV‐DNA and HCV‐RNA were studied by real‐time PCR. The mean age was 49 ± 15 years, and 128 (42%) were female. Serological tests confirmed that all samples were HBsAg negative. Anti‐HBc was positive in 114 (38%) patients, anti‐HBc and anti‐HBs were simultaneously positive in 104 (35%), and anti‐HBc alone was positive in 10 (3%). Tests were negative for anti‐HBc and anti‐HBs in 55 patients (18%). Anti‐HBs was the only positive marker in 132 (44%) patients. Anti‐HCV was positive in 15 (5%) patients with HCV‐RNA present in 14 of them (93%). HBV‐DNA was positive in seven cases (2.3%). There was no association of HBV‐DNA with age, gender, time on dialysis, previous kidney transplant, or HBV serological pattern, but there was a positive correlation with the presence of anti‐HCV (P < 0.001). OHB in chronic renal failure patients on hemodialysis appears to be a relevant finding, suggesting that studying HBV‐DNA in this population using sensitive molecular tests should be a recommended course of action, especially in candidates for renal transplant.     

Catheter‐related bacteremia and mortality in frequent nocturnal home hemodialysis

Frequent nightly home hemodialysis (NHHD) has emerged as an attractive alternative to thrice weekly in‐center hemodialysis, albeit with preponderant long‐term hemodialysis catheter used. Sixty‐three NHHD patients from University of Virginia Lynchburg Dialysis Facility were matched 1:2 with 121 conventional hemodialysis patients admitted to Fresenius Medical Care North America facilities from January 1, 2007 to December 31, 2010. Matching considered age (± 5 years), gender, race, dialysis vintage, and diabetes. The primary end‐point was the combined incidence of bacteremia/sepsis, for up to 20 months or upon changing to a fistula/graft (with catheter removal), transferring to peritoneal dialysis (PD), or at the time of kidney transplant or death. No significant differences were observed in rate of fistula/graft conversion, transfer to PD, transplant, or death between NHHD and in‐center hemodialysis (IHD) groups. For the first catheter used, the rate of catheter‐related sepsis was not significantly different between the NHHD (1.77 per 100 patient months) and IHD (2.03 per 100 patient months; P = 0.21). Combining all catheters, the rate of bacteremia/sepsis per 100 patient months in the NHHD group was 1.51 and in the IHD group was 2.01 (P = 0.35). Median catheter lifespan for the first catheter was 5.6 (1.7～19.0) for NHHD and 4.6 (2.7～7.8) for the IHD group (P = 0.64), and for all catheters used was 5.2 (Q1～Q3 = 1.5～15.2) months in NHHD group, and 4.1 (2.0～6.8) months in IHD group (P = 0.20). The rate of bacteremia and death is not different for up to 20 months in catheter users who dialyze via frequent NHHD vs. thrice weekly IHD.     

Statins are associated with a reduced risk of bone fracture in hemodialysis (HD) patients

The Dialysis Outcomes and Practice Patterns Study reported a statistically non-significant protective effect of HMG-co reductase inhibitors (statins) on bone fracture risk in hemodialysis (HD) patients. We sought to determine whether statin exposure was associated with reduced risk of bone fracture in our HD population. This was a retrospective cohort study of 174 prevalent HD patients. Fracture data are abstracted from the medical record. Subjects were considered to be on a statin if they were exposed at any time since the date of dialysis initiation. The subjects were 174 HD patients (68.4% male) with a median age of 69.1 and age range from 25.2 to 96.3 years. The median age at initiation of HD was 62.5, ranging from 15.2 to 90.5 years. The mean (SD) dialysis vintage was 7.3 (4.5) years. Seventy-seven subjects (44.3%) had statin exposure. There were a total of 54 first bone fractures. There was a positive correlation between bone fracture and dialysis vintage (p=0.023) and a negative association between bone fracture and statin exposure (p=0.044). Those with statin exposure had a higher prevalence of CAD (p=0.030) compared with those not exposed. Logistic regression analysis (stepwise, alpha=0.05) was performed with dependent variable bone fracture and independent variables age at HD initiation (forced), dialysis vintage, gender (forced), prednisone use (forced), and statin exposure. The significant predictors of bone fracture (R2=0.14, p=0.004) were age at HD initiation (p=0.016), dialysis vintage (p=0.007), and absence of statin exposure (p=0.019). Statin exposure appears to be associated with a reduced frequency of bone fracture in HD patients. Future studies evaluating the potential anabolic effect of statins on bone are required.     

The burden of erectile dysfunction in dialysis patients in Senegal

Erectile dysfunction (ED) is very common in dialysis patients because of organic and psychological risk factors. It has a negative impact on patients' quality of life. In Senegal, ED is assumed to be frequent in the general adult population but its prevalence in dialysis patients is unknown. This cross-sectional study aimed to assess the prevalence and risk factors associated with ED in Senegalese dialysis patients. Seventy dialyzed men >18 years old were included. Erectile dysfunction was assessed using the abridged version of International Index of Erectile Function already validated in dialysis patients. Multivariate analysis was performed to identify the factors associated with ED in patients. The mean age of the patients was 52 ± 11.3 years (21-70 years) and the median dialysis vintage was 39.4 months (interquartile range 9-51 months). The prevalence of ED was 81.5% for all patients (80% in hemodialysis and 81.75% in peritoneal dialysis). Severe ED was found in 11.5% of patients. The prevalence of ED was 74.5% in patients younger than 50 years and 86.6% in those 50 years or older. Marital status, comorbidity, hemoglobin level, and use of antihypertensive drugs were not different between patients with and without ED. Libido was conserved in 77% of patients and 44.7% were not satisfied during sexual intercourse. Multivariate analysis identified age and dialysis vintage as risk factors of ED in our patients. Only 7 patients received treatment for ED and 22% sought a consultation with a specialist (urologist and psychologist).     

The use of vascular access audit and infections in home hemodialysis

Vascular access‐related infection is an important adverse event in home hemodialysis (HHD). We hypothesize that errors in self‐cannulation or manipulation of dialysis vascular access are associated with increased incidence of access‐related infection. We conducted a retrospective cohort study of all prevalent HHD patients at the University Health Network. All vascular access‐related infections were recorded from 2006 to 2013. Errors in dialysis access were ascertained by nurse‐administered vascular access checklist. Ninety‐two patients had completed at least one vascular access audit. Median HHD vintage was 2.3 (0.9–5.0) years in patients with appropriate vascular access technique and 5.8 (1.5–9.4) years in patients with erroneous vascular access technique. The overall rate of infection between patients with and without appropriate vascular access technique was similar (0.27 and 0.28 infections per year, P = 0.166). Among patients who were identified with errors in dialysis access manipulation, patients with five or more errors were associated with higher rate of access‐related infection (mean of 0.47 vs. 0.16 infection per patient‐year, P < 0.001). The use of vascular access audit is a feasible strategy, which can identify errors in vascular access technique. Patients with a longer median HHD vintage are associated with higher risk of inappropriate vascular access technique. Patients with multiple errors in vascular access technique are associated with a higher risk of dialysis access‐related infection. Prospective evaluation of the impact of vascular access audit on adverse vascular access events is warranted.     

Nightly home hemodialysis: outcome and factors associated with survival

Nightly home hemodialysis (NHHD) has been reported to have a much better survival than the excessive mortality of thrice-weekly in-center dialysis, but the factors influencing survival of NHHD have not been investigated in detail. We studied the association of survival in a 12-year study of 87 NHHD patients from a single center evaluating demographic, sociologic, and anthropomorphic factors, diagnosis, comorbidity, vintage, and dialysis performance and efficiency. Secondly, we compared the survival of the 87 NHHD patients with that reported by the United States Renal Data System (USRDS) using standardized mortality rate (SMR). The average patient age was 52 ± 15 years, and 59% were males, 51% African Americans, and 25% had diabetes. The patients dialyzed 40 ± 6 hours weekly with a stdKt/V of 5.25 ± 0.84. Thirteen patients died. The cumulative survival was 79% at 5 years and 64% at 10 years. Using Cox proportional hazards univariate analysis, 7 of 26 factors studied were associated with mortality: less than high school education, hour of each dialysis, comorbidities, secondary renal disease, congestive heart failure, Leypoldt's eKt/V, and Daugirdas Kt/V. In backward stepwise Cox analysis, education and hour of dialysis were the only factors independently associated with survival. The standardized mortality rate was only 0.30 of that reported by the United States Renal Data System for patients on thrice-weekly hemodialysis adjusted for age, gender, race, and diagnosis. The influence of education was the most significantly associated with survival, and the duration of each dialysis treatment was important. The survival rate of NHHD patients appeared to be superior to intermittent hemodialysis.     

Occult hepatitis B virus infection of hemodialysis patients: A cross‐sectional study in a hepatitis B virus‐endemic region

Occult hepatitis B virus (HBV) infection is defined as the presence of HBV DNA in the liver tissue and/or serum of subjects seronegative for hepatitis B surface antigen (HBsAg). Occult HBV infection of hemodialysis (HD) patients is informative in terms of virus transmission, reactivation after kidney transplantation, and the progression of liver disease. However, there is little detailed information about occult HBV infection in the context of virus endemicity. We tried to investigate the seroprevalence and clinical features of occult HBV infection in HD patients in HBV‐endemic regions. We enrolled a total of 159 HD patients and 121 apparently healthy subjects at Dankook University Hospital and Jeju National University Hospital in Korea. HBsAg, anti‐HBs, anti‐HBc, and anti‐hepatitis C virus (HCV) antibody levels were measured by radioimmunoassay. Serum levels of HBV DNA were measured by real‐time polymerase chain reaction. The seroprevalence of occult HBV infection was 1.3% in HD patients and 2.5% in the healthy controls. This difference was not significant. The HBV load in all subjects with occult infection was <116 copies/mL, and all were positive for IgG anti‐HBc, regardless of the presence of anti‐HBs. None of the occult HBV‐infected subjects were co‐infected with HCV. One of the 2 HD patients with occult HBV infection had no history of blood transfusion. In this HBV‐endemic region, the seroprevalence of occult HBV infection in HD patients with a very low viral load was not significantly different from that in apparently healthy subjects.     

Occult hepatitis B infection in a hemodialysis population in Guilan province, northern Iran

Hemodialysis (HD) patients are vulnerable to transfusion-transmitted infections such as hepatitis B virus (HBV). HBV infection with undetectable hepatitis B surface antigens (HBsAg) is described as occult HBV and can lead to serious complications. The aim of this study was to evaluate the prevalence of occult HBV and concomitant factors in HD patients. Using a cross-sectional design, clinical and epidemiological data were obtained from May to September 2009 in 11 different HD units in Guilan province in northern Iran. After serological testing for HBV surface antigens in 514 HD patients using a third-generation enzyme-linked immunosorbent assay kit (Diapro, Milano, Italy), HBsAg-negative patients were tested for HBV DNA using a Qiagen PCR kit (Artus Qiagen GmbH, Hilden, Germany). After omission of seven HBsAg-positive patients, 507 patients were included in the study, 280 (55.2%) of whom were male and 227 (44.8%) were female. Patients ranged in age from 16 to 66 years (mean 53.2 years). No HBV DNA was detected in HBsAg-negative patients. Some 59 patients (11.6%) were anti-hepatitis C virus positive and 32 (6.3%) were hepatitis C virus positive according to polymerase chain reaction. The study results indicate that occult HBV infection is not a significant health problem in HD patients in Guilan province.     

Clinical epidemiology of parathyroidectomy in hemodialysis patients: the USRDS waves 1, 3, and 4 study

Despite advances in the medical management of secondary hyperparathyroidism, parathyroidectomy remains necessary in some end-stage renal disease patients. Observational studies may help with the design of intervention trials. We linked the retrospective Waves 1, 3, and 4 Dialysis Morbidity and Mortality Study datasets to Medicare claims data to identify incident parathyroidectomy in 10,588 Medicare patients receiving hemodialysis in the United States on December 31, 1993. The mean age was 60.0 years, and the mean follow-up 3.6 years. De novo parathyroidectomy incidence was 14.2/1000 patient-years. Considered as quintiles (Q), higher levels of standard bone metabolism variables were associated (p<0.0001) with parathyroidectomy stepwise, such that adjusted hazards ratios (AHR) for Q5 (vs. Q1) were, for calcium (>10.3 mg/dL), 5.09 (3.64-7.10); for phosphorus (>7.5 mg/dL), 2.92 (2.06-4.15); for calcium-phosphorus product (>71 mg2/dL2), 3.32 (2.27-4.85); and for parathyroid hormone (PTH; >480 pg/mL), 13.81 (7.47-25.55). Other antecedent associations included younger age, lower hemoglobin, and longer dialysis vintage, while transplantation, as a time-dependent covariate, was associated with lower hazards ratios. Using interval Poisson analysis, parathyroidectomy was associated with higher mortality risk ratios in the first year, and progressively lower risk ratios subsequently. Demographic variables may modify the risk of parathyroidectomy. Younger patients on long-term hemodialysis may be at a special risk. Parathyroidectomy risk increases stepwise with alterations in bone metabolism variables, suggesting that a single-threshold management approach may not be ideal.     

Impact of advanced dialysis technology on the prevalence of dialysis‐related amyloidosis in long‐term maintenance dialysis patients

Dialysis‐related amyloidosis (DRA) is a unique type of amyloidosis (beta‐2 microglobulin) predominantly in end‐stage renal disease. Its clinical manifestations add to increased morbidity and reduced quality of life. There seems to be a relative risk reduction in DRA manifestations when hemodialysis (HD) patients are treated with advanced HD technology, but changes of the course of DRA are uncertain. The aim of our investigation was to evaluate the prevalence and severity of carpal tunnel syndrome (CTS) in long‐term dialysis patients receiving either conventional or high‐flux, online‐produced ultrapure dialysis fluid. The cross‐sectional study included 147 HD patients (at least 10 years). The definitive diagnosis of CTS was made histologically or by the coexistence of CTS with other radiological DRA manifestations (bone cysts, arthropathies). The two HD patient groups did not differ significantly in age at start of HD, gender, major co‐morbid diseases, anuria, and dialysis vintage. The conventional HD group had significantly higher circulating beta‐2 microglobulin and C‐reactive protein (CRP) levels. The prevalence of DRA was 68% for the conventional HD group and 28% for the advanced HD group. Duration of dialysis treatment was the only significant risk factor for the development of clinical DRA manifestations in both study groups, but CTS, bone cysts, or arthropathies occurred significantly earlier in conventional HD patients. The prevalence and severity of DRA have decreased with advances in dialysis technology during the last two decades, although its occurrence is simply delayed.     

Determinants of survival in patients receiving dialysis in Libya

Maintenance dialysis is associated with reduced survival when compared with the general population. In Libya, information about outcomes on dialysis is scarce. This study, therefore, aimed to provide the first comprehensive analysis of survival in Libyan dialysis patients. This prospective multicenter study included all patients in Libya who had been receiving dialysis for >90 days in June 2009. Sociodemographic and clinical data were collected upon enrolment and survival status after 1 year was determined. Two thousand two hundred seventy‐three patients in 38 dialysis centers were followed up for 1 year. The majority were receiving hemodialysis (98.8%). Sixty‐seven patients were censored due to renal transplantation, and 46 patients were lost to follow‐up. Thus, 2159 patients were followed up for 1 year. Four hundred fifty‐eight deaths occurred, (crude annual mortality rate of 21.2%). Of these, 31% were due to ischemic heart disease, 16% cerebrovascular accidents, and 16% due to infection. Annual mortality rate was 0% to 70% in different dialysis centers. Best survival was in age group 25 to 34 years. Binary logistic regression analysis identified age at onset of dialysis, physical dependency, diabetes, and predialysis urea as independent determinants of increased mortality. Patients receiving dialysis in Libya have a crude 1‐year mortality rate similar to most developed countries, but the mean age of the dialysis population is much lower, and this outcome is thus relatively poor. As in most countries, cardiovascular disease and infection were the most common causes of death. Variation in mortality rates between different centers suggests that survival could be improved by promoting standardization of best practice.     

Confounding factors for early death in incident end‐stage renal disease patients: Role of emergency dialysis start

Hemodialysis (HD) has been associated with higher 1‐year mortality than peritoneal dialysis (PD) after dialysis start. Confounding effects of late referral, emergency dialysis start, or start with central venous catheter on this association have never been studied concomitantly. Survival was studied among the 495 incident dialysed patients in our department from 1995 to 2006 and followed at least 1 year until December 31, 2007. Nested Cox models adjusted on patient characteristics explored factors associated with 1‐year and ≥1‐year mortality. Hemodialysis patients were 332 (67.1%), 104 (21.0%) were late referred (<6 months), 167 (33.7%) started dialysis in emergency, and 144 (29.1%) started with central venous catheter. When adjusted only on age, sex, and comorbidities, HD was associated with poor 1‐year outcome: adjusted hazard ratio (aHR) for death in HD vs. PD was 1.77, P=0.02. In fully adjusted model, among first dialysis feature variables, only emergency dialysis start was significantly associated with 1‐year mortality: aHR 1.53, P=0.02. Dialysis modality was not associated with 1‐year mortality rates in this fully adjusted model: aHR in HD vs. PD became 1.03, P=0.91. In ≥1‐year period, HD was associated with lower mortality than PD (aHR 0.61, P=0.004), whereas other first dialysis features were not associated with death. Other factors associated with death were age, type 2 diabetes, peripheral vascular disease, heart failure, and hepatic failure. Negative association between HD and 1‐year survival on dialysis was explained by confounders. Emergency dialysis start was strongly associated with early mortality on dialysis. Its prevention may improve patient survival.     

Factors predicting failure of AV “fistula first” policy in the elderly

An arteriovenous fistula (AVF) is the preferential hemodialysis (HD) access. The goal of this study was to identify factors associated with pre‐dialysis AVF failure in an elderly HD population. We used United States Renal Data System + Medicare claims data to identify patients ≥67 years old who had an AVF as their initial vascular access placed pre‐dialysis. Failure of the AVF to be used for initial HD, was used as the outcome. Logistic regression model was used to identify factors associated with AVF failure. The study cohort consisted of 20,360 subjects (76.2 ± 6.02 year old, 58.5% men). Forty‐eight percent of patients initiated dialysis using an AVF, while 52% used a catheter or an AVG. The following variables found to be associated with AVF failure when an AVF was created at least 4 months pre‐HD initiation: older age (odds ratio [OR] 1.01; 95% confidence interval [CI] 1.00–1.02), female gender (OR 1.69; 95% CI 1.55–1.83), black race (OR 1.41; 95% CI 1.26–1.58), history of diabetes (OR 1.22; 95% CI 1.06–1.39), cardiac failure (OR 1.26; 95% CI 1.15–1.37), and shorter duration of pre–end‐stage renal disease (ESRD) nephrology care (OR for a nephrology care of less than 6 months prior to ESRD of 1.22 compared with a pre‐ESRD nephrology follow up of more than 12 months; 95% CI 1.07–1.38). OR for AVF failure for the entire cohort showed similar findings. In an elderly HD population, there is an association of older age, female gender, black race, diabetes, cardiac failure and shorter pre‐ESRD nephrology care with predialysis AVF failure.     

D‐dimer levels in maintenance hemodialysis patients: High prevalence of positive values also in the group without predisposing diseases

We aimed to estimate the prevalence of elevated D‐dimer levels in all chronic hemodialysis patients and those without additional disease, and to identify factors associated with increased D‐dimer. In 167 chronic hemodialysis patients from our center, D‐dimer was measured before dialysis. The effects of age, C‐reactive protein (CRP), recent acute illness, vascular access, anticoagulation type, dialysis vintage, and chronic diseases, considered to predispose for increased D‐dimer levels, were analyzed. The median D‐dimer in the whole group was 966 (inter‐quartile range [IQR] 524–1947) μg/L and was positive (>500 μg/L) in 75% of cases. D‐dimer was positive in 91% of patients with acute illness, 76% of those with predisposing chronic diseases, but was still positive in 52% of patients without additional disease (i.e., acute illness or predisposing chronic diseases) – median D‐dimer was 538.5 (IQR 359–966) μg/L. D‐dimer was correlated to patients' age, but not dialysis vintage. In univariate analysis, the D‐dimer levels were significantly higher in patients with atrial fibrillation, ischemic heart disease, recent acute illness, increased CRP, dialyzed over a catheter, and on citrate anticoagulation. Multivariate logistic regression showed that only age >65 years (odds ratio [OR] 2.93), catheter (OR 4.86), and positive CRP (OR 4.07) were independently associated with positive D‐dimer at 500 μg/L cut‐off, while the significance of age disappeared at 2000 μg/L cut‐off. To conclude, the high prevalence of positive D‐dimer values even in hemodialysis patients without additional disease limits the use of D‐dimer for exclusion of thromboembolic diseases in hemodialysis patients.     

Superior patient and technique survival with very high standard Kt/V in quotidian home hemodialysis

We studied the association of patient and dialysis factors with patient and technique survival in a cohort of all of our 191 of patients surviving >3 months on quotidian home hemodialysis (QHHD). Eighty‐one patients were on nocturnal QHHD and 110 on short ‐daily QHHD. Weekly dialysis time was 7.5–48 hours, single pool Kt/V was 0.38–4.5 per treatment, and weekly standardKt/V was 2.1–7.5. The association of 18 patient and dialysis variables with patient and technique survival was analyzed by Kaplan‐Meier and Cox analyses. Ninety‐nine patients (52%) remained on QHHD, 34 (18%) were transplanted, 31 (16%) returned to 3/week HD, and 27 (14%) died. The 5‐year patient survival was 71% ± 6% (night: 79% ± 7%, day: 69% ± 9%, P = 0.002). The 5‐year technique survival was 80% ± 4% (night: 93% ± 3%, day: 46% ± 17%, P = 0.001). In Cox analyses, patient survival was independently associated with standard Kt/V (hazard ratio [HR] = 0.29, P < 0.0001), graduating from high school (HS) (HR = 0.11, P = 0.0002), and use of graft/fistula (HR = 0.22, P = 0.007). Technique survival was independently associated with standard Kt/V (HR = 0.50, P = 0.0003) and start of QHHD after 2003 (HR = 0.18, P = 0.007). Every increase in standard Kt/V was associated with improved survival. The highest survival occurred when standard Kt/V exceeded 5.1, only possible when weekly dialysis hours exceed 35 hours. In QHHD, higher standard Kt/V, education, and subcutaneous access are associated with better patient survival and higher standard Kt/V and longer experience of center with better technique survival. There was no upper limit of standard Kt/V, where survival plateaus. The amount of minimally “adequate” dialysis should be much increased.     

Survival to discharge among patients treated with CRRT

The optimal acid base status for survival in maintenance hemo‐dialysis (MHD) patients (pts) remains controversial. According to some reports acidosis is associated with improved survival in MHD pts, i.e., reverse epidemiology. We examined associations between baseline (first 3‐month averaged) serum bicarbonate (HCO₃), divided into 12 categories, and 2‐yr mortality in 56,376 MHD pts across the US after controlling for confounding effects of malnutrition‐inflammation complex syndrome (MICS). Three sets of Cox regression models were evaluated to estimate hazard ratios (HR) of death and 95% confidence intervals (CI): (1) Unadjusted; (2) Multivariate adjusted for case‐mix (age, gender, diabetes, race, insurance, marital status, vintage, standardized mortality ratio, residual renal function, dialysate HCO₃, and Kt/V); and (3) Additional adjustments for 8 markers of MICS (body mass index, serum albumin, creatinine, ferritin, TIBC, dietary protein intake, WBC and lymphocyte counts). See Figure for HR and 95% CI:
We conclude that, although high HCO₃ levels appear to be associated with increased mortality in MHD pts, this paradoxical effect is almost entirely due to the overwhelming impact of MICS on survival.     

Malnutrition‐inflammation‐coronary calcification in pediatric patients receiving chronic hemodialysis

Malnutrition, inflammation, and renal osteodystrophy parameters with resultant coronary calcification (CC) are associated with increased cardiovascular mortality in adults. Previous pediatric studies demonstrated CC in children but none assessed for an association between inflammation, malnutrition, renal osteodystrophy, and CC. To assess CC, ultrafast computerized tomogram was obtained for 16 pediatric patients (6 females; median age 17.2 years; range 9.1–21.2 years) receiving hemodialysis for ≥2 months. Inflammation was assessed by serum IL‐6, IL‐8, and C‐reactive protein levels on the day of the computerized tomogram scan; nutrition parameters included serum albumin, cholesterol, the body mass index standard deviation score, and normalized protein catabolic rate. Renal osteodystrophy parameters included time‐averaged serum calcium, phosphorus, total PTH, and calcitriol/calcium dose. Patients received hemodialysis thrice‐weekly; mean single pool Kt/V 1.48±0.13; and mean normalized protein catabolic rate 1.27±0.17 g/kg/day. Five of 16 patients had CC. Patients with CC were older (19.1±2.1 vs. 15.4±3.1 months; P=0.03), had longer dialysis vintage (49.4±15.3 vs. 17.2±10.5 months, P=0.0002), lower serum cholesterol (122±17.7 vs. 160.4±10.6 mg/dL, P=0.02), and higher phosphorus (9.05±1.2 vs. 6.1±0.96 mg/dL, P=0.0001). Mean serum albumin and normalized protein catabolic rate did not differ for patients with CC. All patients had elevated IL‐6 and IL‐8 levels compared with healthy norms; the mean IL‐6, IL‐8, and C‐reactive protein levels were not different in patients with CC. Coronary calcification was prevalent in older children receiving maintenance hemodialysis with a longer dialysis vintage. Worse renal osteodystrophy control and malnutrition (low cholesterol) may contribute to CC development.     

Exceeding hemoglobin target levels in US hemodialysis patients receiving epoetin, 1999 to 2002

Despite emerging concerns that exceeding anemia targets with erythropoiesis stimulating agents may be risky for hemodialysis patients, the magnitude of and risk factors for the problem have received little attention, particularly regarding year-to-year comparisons. We studied monthly hemoglobin and epoetin levels in 41,101 patients aged at least 65 years who initiated hemodialysis between 1999 and 2002, with upper targets defined by hemoglobin levels of 120 and 130 g/L, respectively. While baseline hemoglobin values and epoetin doses rose from year to year, their rates of change during follow-up declined (p<0.0001). Similar patterns were seen after reaching hemoglobin levels of 110 g/L; comparing 1999 to 2002, the proportions reaching 120 and 130 g/L in the ensuing 9 months increased from 90% to 96% (p<0.0001) and from 56% to 69%, respectively (p<0.0001). Multivariate analysis showed that, while more recent years of dialysis inception and initial epoetin dose were associated with all 3 outcomes, higher baseline hemoglobin levels were associated with reaching levels of 110 and 120 g/L, but not 130 g/L. Exceeding hemoglobin level targets has become widespread in the United States and is associated with changes in epoetin dosing practices.     

Survival Advantage of Tailored Dialysis

Survival has been defined as an index of adequacy of dialysis. These hard data are the basis for comparing results obtained by different schedules or policies. The aim of the study was to assess mortality rate recorded within a system of tailored dialysis (1–6 dialysis per week in out‐of‐hospital settings: home hemodialysis, self‐ and limited care dialysis). Data recorded in a single center (1998–2003) were compared with data gathered in the Registry of Dialysis and Transplantation in the whole Region (1998–2000). Methods: Out‐of‐hospital dialysis unit is active since 1971, in which a new program integrating self‐ and limited care and home dialysis started since 1998. Patients: Incident dialysis patients starting renal replacement therapy within the program and all further patients starting dialysis in the Region in the same period were compared in an historical prospective cohort study. Results: 55 patients in the Unit and further 1443 patients in the whole Region started RRT since 1998. Main features of 55 patients were 32 males 23 females; median age 51 years, range 20–76; 72.7% displaying at least 1 comorbid factor. Throughout the period gross mortality rate was 4/125 patient‐years in the Center. Kaplan–Meier curves showed a 1‐year survival of 100% vs. 91%, respectively, in the Center and in the whole Region, and a 2‐year survival of 95.5% vs. 76.6%, respectively, in the Center and in the whole Region (p = 0.001). The main demographic features were remarkably different in both settings (for the whole Region median age 66 years, range 2.2–101, at least 1 comorbidity in 56.9% of patients). In an attempt to correct for the different baseline characteristics, a multivariate Cox regression analysis was performed. The whole model resulted in statistically significant value (p = 0.000) and an increasing mortality risk resulted for age at starting dialysis, diabetes, and collagenopathy. In conclusion, tailored, high‐efficiency dialysis policy may allow superior survival results. A longer follow up is needed to confirm our approach; in larger cohorts, the finding of a low mortality rate in a relatively young population with high comorbidity may underline the need to review our current concepts on dialysis adequacy.