Adult Dialysis Research Articles

Effects of Different Models of Dialysis Care on Patient-Important Outcomes: A Systematic Review and Meta-Analysis.

Ongoing payment reform in dialysis necessitates better patient outcomes and lower costs. Suggested improvements to processes of care for maintenance dialysis patients are abundant; however, their impact on patient-important outcomes is unclear. This systematic review included comparative randomized controlled trials or observational studies with no restriction on language, published from 2000 to 2014, involving at least 5 adult dialysis patients who received a minimum of 6 months of follow-up. The effect size was pooled and stratified by intervention strategy (multidisciplinary care [MDC], home dialysis, alternate dialysis settings, and electronic health record implementation). Heterogeneity (I2) was used to assess the variability in study effects related to study differences rather than chance. Of the 1988 articles screened, 25 international studies with 74,833 maintenance dialysis patients were included. Interventions with MDC or home dialysis were associated with a lower mortality (hazard ratio [HR] = 0.72, 95% confidence interval [CI] 0.61, 0.84, I2 = 41.6%; HR = 0.57, 95% CI 0.41, 0.81, I2 = 89.0%; respectively) and hospitalizations (incidence rate ratio [IRR] = 0.68, 95% CI 0.51, 0.91, I2 = NA; IRR = 0.88, 95% CI 0.64, 1.20, I2 = 79.6%; respectively). Alternate dialysis settings also were associated with a reduction in hospitalizations (IRR = 0.41, 95% CI 0.25, 0.69, I2 = 0.0%). This systematic review underscores the importance of multidisciplinary care, and also the value of telemedicine as a means to increase access to providers and enhance outcomes for those dialyzing at home or in alternate settings, including those with limited access to nephrology expertise because of travel distance.

Medication adherence in randomized controlled trials evaluating cardiovascular or mortality outcomes in dialysis patients: A systematic review

BackgroundMedication non-adherence is common among renal dialysis patients. High degrees of non-adherence in randomized controlled trials (RCTs) can lead to failure to detect a true treatment effect. Cardio-protective pharmacological interventions have shown no consistent benefit in RCTs involving dialysis patients. Whether non-adherence contributes to this lack of efficacy is unknown. We aimed to investigate how medication adherence and drug discontinuation were assessed, reported and addressed in RCTs, evaluating cardiovascular or mortality outcomes in dialysis patients.MethodsElectronic database searches were performed in MEDLINE, EMBASE & Cochrane CENTRAL for RCTs published between 2005–2015, evaluating self-administered medications, in adult dialysis patients, which reported clinical cardiovascular or mortality endpoints, as primary or secondary outcomes. Study characteristics, outcomes, methods of measuring and reporting adherence, and data on study drug discontinuation were analyzed.ResultsOf the 642 RCTs in dialysis patients, 22 trials (12 placebo controlled), which included 19,322 patients, were eligible. The trialed pharmacological interventions included anti-hypertensives, phosphate binders, lipid-lowering therapy, cardio-vascular medications, homocysteine lowering therapy, fish oil and calcimimetics. Medication adherence was reported in five trials with a mean of 81% (range: 65–92%) in the intervention arm and 84.5% (range: 82–87%) in the control arm. All the trials that reported adherence yielded negative study outcomes for the intervention. Study-drug discontinuation was reported in 21 trials (mean 33.2%; 95% CI, 22.0 to 44.5, in intervention and 28.8%; 95% CI, 16.8 to 40.8, in control). Trials with more than 20% study drug discontinuation, more often yielded negative study outcomes (p = 0.018). Non-adherence was included as a contributor to drug discontinuation in some studies, but the causes of discontinuation were not reported consistently between studies, and non-adherence was listed under different categories, thereby potentiating the misclassification of adherence.ConclusionsReporting of medication adherence and study-drug discontinuation in RCTs investigating cardiovascular or mortality endpoints in dialysis patients are inconsistent, making it difficult to compare studies and evaluate their impact on outcomes. Recommendations for consistent reporting of non-adherence and causes of drug discontinuation in RCTs will therefore help to assess their impact on clinical outcomes.

Carvedilol and Cardiac Biomarkers in Dialysis Patients: Secondary Analysis of a Randomized Controlled Trial

Background/Aims: Cardiac biomarkers are associated with cardiac abnormalities and adverse outcomes in dialysis patients. Our aim was to report the effect of the beta-blocker carvedilol on cardiac biomarkers in adult dialysis patients. Methods: The Beta-Blocker to Lower Cardiovascular Dialysis Events Feasibility Study was a randomized controlled trial comparing carvedilol to placebo. Serum and plasma were collected before the run-in, then 6 and 12 months post-randomization to measure B-type Natriuretic Peptide (BNP), N-terminal BNP (NT-ProBNP), high-sensitivity cardiac troponins I (hs-TnI) and T (hs-TnT), and galectin-3. Left ventricular global longitudinal strain (GLS) was measured by echocardiography at baseline. Results: Seventy-two participants were recruited of whom 49 completed the run-in and were randomized to carvedilol (n=26) or placebo (n=23). Baseline echocardiography demonstrated median (inter-quartile range) GLS of -14.27% (-16.63 to -11.93). NTproBNP and hs-TnT correlated with GLS (Spearman’s rho=0.34 [p=0.018] and rho=0.28 [p=0.049], respectively). Median change scores from baseline to 12 months did not differ significantly between participants with complete biomarker data randomized to carvedilol (n=15) or placebo (n=16) for any biomarkers. Conclusions: NT-proBNP and hs-TnT were associated with GLS. However, changes in levels of the biomarkers from baseline to 12 months were not different between groups randomized to carvedilol and placebo.

Fabry disease in adult dialysis patients in a community hospital

Fabry disease in adult dialysis patients in a community hospital

Racial-ethnic disparities in mortality and kidney transplant outcomes among pediatric dialysis patients.

Previous studies in adult hemodialysis patients have shown that African-American and Hispanic patients have a lower risk of mortality in addition to a lower likelihood of kidney transplantation. However, studies of the association between race and outcomes in pediatric dialysis are sparse and often do not examine outcomes in Hispanic children. The objective was to determine if racial-ethnic disparities in mortality and kidney transplantation outcomes exist in pediatric dialysis patients. This was a retrospective cohort analysis of 2,697 pediatric dialysis patients (aged 0-20 years) from a large national dialysis organization (entry period 2001-2011) of non-Hispanic white, African-American, and Hispanic race-ethnicity. Associations between race-ethnicity with mortality and kidney transplantation outcomes were examined separately using competing risks methods. Logistic regression analyses were used to examine the association between race-ethnicity, with outcomes within 1year of dialysis initiation. Of the 2,697 pediatric patients in this cohort, 895 were African-American, 778 were Hispanic, and 1,024 were non-Hispanic white. After adjusting for baseline demographics, competing risk survival analysis revealed that compared with non-Hispanic whites, African-Americans had a 64% higher mortality risk (hazards ratio [HR] = 1.64; 95% CI 1.24-2.17), whereas Hispanics had a 31% lower mortality risk (HR = 0.69; 95% CI 0.47-1.01) that did not reach statistical significance. African-Americans also had higher odds of 1-year mortality after starting dialysis (odds ratio [OR] = 2.08; 95% CI 0.95-4.58), whereas both African-Americans and Hispanics had a lower odds of receiving a transplant within 1year of starting dialysis (OR = 0.28; 95% CI 0.19-0.41 and OR = 0.43; 95% CI 0.31-0.59 respectively). In contrast to adults, African-American pediatric dialysis patients have worse survival than their non-Hispanic white counterparts, whereas Hispanics have a similar to lower mortality risk. Both African-American and Hispanic pediatric dialysis patients had a lower likelihood of kidney transplantation than non-Hispanic whites, similar to observations in the adult dialysis population.

The Role of RRT in Hyperammonemic Patients.

Hyperammonemia is an important cause of cerebral edema in both adults with liver failure and children with inborn errors of metabolism. There are few studies that have analyzed the role of extracorporeal dialysis in reducing blood ammonia levels in the adult population. Furthermore, there are no firm guidelines about when to implement RRT, because many of the conditions that are characterized by hyperammonemia are extremely rare. In this review of existing literature on RRT, we present the body's own mechanisms for clearing ammonia as well as the dialytic properties of ammonia. We review the available literature on the use of continuous venovenous hemofiltration, peritoneal dialysis, and hemodialysis in neonates and adults with conditions characterized by hyperammonemia and discuss some of the controversies that exist over selecting one modality over another.

Height at First RRT and Mortality in Children.

Poor linear growth is common in children with CKD and has been associated with higher mortality. However, recent data in adult dialysis patients have suggested a higher risk of death in persons of tall stature. In this study, we aimed to examine the risk of all-cause and cause-specific mortality in children at both extremes of height at the time of first RRT. Using the US Renal Data System, we performed a retrospective analysis of 13,218 children aged 2-19 years, who received their first RRT (dialysis or transplant) during 1995-2011. We used adjusted Cox models to examine the association between short (<3rd percentile) and tall (>3rd percentile) stature and risk of death, compared with less extreme heights. Over a median follow-up of 7.1 years, there were 1721 deaths. Risk of death was higher in children with short (hazard ratio, 1.49; 95% confidence interval, 1.33 to 1.66) and tall stature (hazard ratio, 1.32; 95% confidence interval, 1.03 to 1.69) in adjusted analysis. In secondary analyses, there was a statistically significant interaction between height and body mass index categories (P=0.04), such that the association of tall stature with higher mortality was limited to children with elevated body mass index (defined as ≥95th percentile for age and sex). Children with short stature had a higher risk of cardiac- and infection-related death, whereas children with tall stature had a higher risk of cancer-related death. Children with short and tall stature are at higher mortality risk, although this association was modified by body mass index at time of first RRT. Studies to further explore the reasons behind the higher risk of mortality in children with extremes of height at the time of first RRT are warranted.

Standardized Prevalence Ratios for Atrial Fibrillation in Adult Dialysis Patients in Japan

BackgroundWhile it is assumed that dialysis patients in Japan have a higher prevalence of atrial fibrillation (AF) than the general population, the magnitude of this difference is not known.MethodsStandardized prevalence ratios (SPRs) for AF in dialysis patients (n = 1510) were calculated compared to data from the general population (n = 26 454) living in the same area.ResultsThe prevalences of AF were 3.8% and 1.6% in dialysis patients and the general population, respectively. In male subjects, these respective values were 4.9% and 3.3%, and in female subjects they were 1.6% and 0.6%. The SPRs for AF were 2.53 (95% confidence interval [CI], 1.88–3.19) in all dialysis patients, 1.80 (95% CI, 1.30–2.29) in male dialysis patients, and 2.13 (95% CI, 0.66–3.61) in female dialysis patients.ConclusionsThe prevalence of AF in dialysis patients was twice that in the population-based controls. Since AF strongly contributes to a higher risk of cardiovascular mortality and morbidity in the general population, further longitudinal studies should be conducted regarding the risk of several outcomes attributable to AF among Japanese dialysis patients.

Survival With Dialysis Versus Kidney Transplantation in Adult Hemolytic Uremic Syndrome Patients: A Fifteen-Year Study of the Waiting List.

Survival data are lacking for kidney transplant recipients with rare native end-stage renal disease (ESRD) etiologies. There is currently no large registry study comparing dialysis versus kidney transplantation survival outcomes of waitlisted adults with hemolytic uremic syndrome (HUS). We retrospectively studied adult-HUS end-stage renal disease patients (n = 559) placed on the US kidney transplant waitlist in 1996 to 2011. We analyzed 5-year transplantation and patient survival probabilities and risk factors using Kaplan-Meier and Cox hazards models, respectively. Using similar models, waitlist and transplantation outcomes of patients with diabetes mellitus (DM), hypertension (HTN), and glomerulonephritis (GN) were analyzed, and then compared with HUS patients. Compared with waitlisted adult HUS patients on dialysis, 5-year mortality risks were 73% and 48% lower in recipients of living (hazard ratio [HR], 0.27, 95% confidence interval [95% CI], 0.11-0.65) and standard deceased (HR, 0.52; 95% CI, 0.29-0.94) donor kidney transplants, respectively. Mortality risks over 5 years were 44%, 50%, 54%, and 55% lower in the overall transplant recipient cohorts than in the dialysis-maintained cohorts within the HUS (HR, 0.56; 95% CI, 0.35-0.91), HTN (HR, 0.50; 95% CI, 0.48-0.52), GN (HR, 0.46; 95% CI, 0.44-0.49), and DM (HR, 0.45; 95% CI, 0.44-0.47) groups, respectively. Five-year transplantation probability in the waitlisted HUS cohort was 60% versus 42% to 49% (P < 0.001) in the DM and HTN cohorts, and 62% (P = 0.93) in the GN cohort. Living and standard criteria deceased donor kidney transplants provide significant survival benefit over dialysis in waitlisted adults with HUS. On the waitlist, the 5-year transplantation probability was higher in HUS than in DM and HTN patients.

A Study on Bacteriological Profile of Blood Culture Sample from Dialysis Patients

Hemodialysis and peritoneal dialysis are reasons for chronic glomerulonephritis, diabetic nephropathy, polycystic kidney disease, chronic interstitial nephritis, and vasculitis. Dialysis is lifesaving for kidney malfunctioned patients, and in the absence of this intervention, kidneys no longer function resulting in the death of the patients due to electrolyte abnormalities and build up of toxins in the blood stream. Coinfection with other bacterial or fungal organisms is observed more frequently in dialysis failure patients. The study population had a total of 144 adult dialysis subjects comprising 78 male (55%) and 66 female (45%). Among them, blood samples of 32 patients (22% of total study population) were found to be infected with pathogenic bacteria as these samples were positive to culture. All these isolates were distinguished at the species level. Finally, it is concluded that the dialysis patients have to be often screened and diagnosed for bacterial infections. Broad spectrum of antibiotics may be prescribed if symptoms of bacterial infections suspected before diagnosis. Earlier diagnosis with prescription of appropriate dose of drugs will not only enable to avoid the morbidity of bacterial infections but also prevent the infection associated complications and thereby reduce the mortality.

SUN-PP147: Peritoneal Dialysis in Older Adults: Evaluation of Clinical, Nutritional, and Metabolic Outcomes

SUN-PP147: Peritoneal Dialysis in Older Adults: Evaluation of Clinical, Nutritional, and Metabolic Outcomes

1D.05

Objective: The loss of physiological stiffness mismatch between aorta and peripheral arteries was strongly and independently associated with increased mortality in adult dialysis population. The aim of the study was to evaluate if the reversal of arterial stiffness mismatch was present in pre-dialysis patients with chronic kidney disease (CKD). Design and method: The aortic-brachial arterial stiffness mismatch (pulse wave velocity (PWV ratio) were assessed using carotid-femoral PWV divided by carotid-radial PWV in 112 adult treated hypertensive CKD patients: 54 - with CKD IIIa (age 59,5 ± 8,4 years, male 46,3%, brachial blood pressure (BP) 149,6 ± 10,3/85,8 ± 9,8 mmHg), 35 - with CKD IIIb (age 60,2 ± 7,8 years, male 45,7%, BP 152,5 ± 12,5/86,4 ± 10,2 mmHg) and 23 with CKD IV (age 57,3 ± 10,2, male 43,4%, BP 156,1 ± 14,3/92,8 ± 12,4 mmHg). P < 0,05 was considered significant for group comparisons, Spearman correlation test and multivariate regression analysis. Results: In CKD IIIa aortic PWV was 10,2 ± 2,0 m/s, brachial PWV 12,9 ± 1,6 m/s, PWV ratio 0,82 ± 0,25. In CKD IIIb aortic PWV was 11,3 ± 2,9 m/s, brachial PWV 12,2 ± 1,8 m/s, PWV ratio 0,90 ± 0,27. In CKD IV aortic PWV was 12,7 ± 3,1 m/s (p < 0,05 vs CKD IIIa), brachial PWV 11,4 ± 1,6 m/s (p < 0,05 vs CKD IIIa), PWV ratio 1,09 ± 0,33 (p < 0,05 vs CKD IIIa). Increased aortic stiffness (aortic PWV>10 m/s) was observed in 55,6%, 62,9% and 73,9%, respectively. For the whole study population (n = 112) multivariate analysis revealed independent significant correlation between aortic PWV and glomerular filtration rate (GFR) β=-0,36 (p < 0,05), PWV ratio and GFR β=-0,32 (p < 0,05), PWV ratio and age β=0,44 (p < 0,05). Conclusions: In the pre-dialysis hypertensive CKD patients worsening of kidney function was associated with discordant changes in aortic and brachial artery stiffness in the reversal of the physiological stiffness mismatch. The loss of this physiological mismatch may promote kidney damage through increased forward pressure wave transmission into the microcirculation. PWV ratio evaluation (in addition to traditional aortic PWV measurement) may be useful for better evaluation of arterial stiffness in pre-dialysis CKD patients.

Bone histomorphometry before and after long-term treatment with cinacalcet in dialysis patients with secondary hyperparathyroidism

The multicenter, single-arm BONAFIDE study characterized the skeletal response to cinacalcet in adult dialysis patients with plasma parathyroid hormone (PTH) levels of 300 pg/ml or more, serum calcium of 8.4 mg/dl or more, bone-specific alkaline phosphatase over 20.9 ng/ml and biopsy-proven high-turnover bone disease. Of 110 enrolled patients, 77 underwent a second bone biopsy with quantitative histomorphometry after 6–12 months of cinacalcet treatment. The median PTH decreased from 985 pg/ml at baseline to 480 pg/ml at the end of study (weeks 44–52). Bone formation rate/tissue area decreased from 728 to 336 μm2/mm2/day, osteoblast perimeter/osteoid perimeter decreased from 17.4 to 13.9%, and eroded perimeter/bone perimeter decreased from 12.7 to 8.3%. The number of patients with normal bone histology increased from none at baseline to 20 at 12 months. Two patients had adynamic bone at the end of study with a PTH under 150 pg/ml, and one patient with overt hypophosphatemia at baseline that reoccurred during follow-up developed osteomalacia. Thus, long-term treatment with cinacalcet substantially reduced PTH, diminished the elevated bone formation rate/tissue area, lowered several biochemical markers of high-turnover bone disease toward normal, and generally improved bone histology. Twenty patients had normal bone histology at follow-up, whereas most had mild hyperparathyroidism or mixed uremic osteodystrophy.

Uremic pruritus

Uremic pruritus

Cost-effectiveness of kidney transplantation compared with chronic dialysis in end-stage renal disease.

To estimate the costs and effectiveness measured in quality-adjusted life years (QALY) of kidney transplantation compared with dialysis in adults suffering from end-stage renal disease from the perspective of the Colombian healthcare system, we designed a Markov model with monthly cycles over a five-year time horizon and eight transitional states, including death as an absorbing state. Transition probabilities were obtained from international registries, costs from different local sources [case studies, official tariffs (ISS 2001 + 35%) for procedures and SISMED for medications]. Data were validated by an expert panel and we performed univariate, multivariate and probabilistic sensitivity analyses. Effectiveness indicators were months of life gained, months of dialysis averted and deaths prevented. The annual discount rate was 3% and the cost-utility threshold (willingness to pay) was three times gross domestic product (GDP) = USD 20,000 per QALY. The costs were adopted in US dollars (USD) using the 2012 average exchange rate (1 USD = COP$ 1798). The discounted average total cost for five years was USD 76,718 for transplantation and USD 76,891 for dialysis, with utilities 2.98 and 2.10 QALY, respectively. Additionally, renal transplantation represented 6.9 months gained, 35 months in dialysis averted per patient and one death averted for each of the five patients transplanted in five years. We conclude that renal transplantation improves the overall survival rates and quality of life and is a cost-saving alternative compared with dialysis.

Level of dietary awareness among Saudi dialysis patients and the influence of various factors.

Our objective was to investigate the degree of dietary awareness of Saudi patients on chronic hemodialysis and influencing factors on this awareness. This is an interviewadministered survey-based cross-sectional study carried out on adult dialysis patients at the King Abdulaziz Medical City, Riyadh. The first part of the survey consisted of the collection of demographic data and the second part consisted of questions in the areas of awareness on the dietary influence of sodium, potassium, fluid intake and calcium/phosphorous and lipids. The questions are simply answered as "yes" or "no." The overall awareness score was 79%. The awareness scores were highest in the area of lipids (86.5%) and lowest in the fluid intake area (71.3%). The scores for sodium, phosphorous/calcium and potassium were 80%, 79.6% and 73%, respectively. The degree of awareness was influenced by the number of visits by the dietitian (P = 0.008) and the educational level of the patients (P = 0.02), but not by age, duration on dialysis or gender. In conclusion, our findings suggest that there is a need for better of awareness among our dialysis patients. The highest score for awareness was seen in the cholesterol-related questions and the lowest score was seen in the fluid intake questions area. This is influenced by the number of visits by the dietitian and the educational level of the patients, but not by age, duration on dialysis or gender.

Intact parathyroid hormone and whole parathyroid hormone assay results disagree in hemodialysis patients under cinacalcet hydrochloride therapy.

BackgroundThe parathyroid gland secretes 1-84 and 7-84 parathyroid hormone (PTH) fragments, and its regulation is dependent on stimulation of the extracellular calcium-sensing receptor. While the intact PTH system detects both PTH fragments, the whole PTH system detects the 1-84PTH but not the 7-84PTH. Cinacalcet hydrochloride (CH) binds to calcium-sensing receptor as a calcimimetic. Here we investigated the role of CH treatment in the assessment of parathyroid gland function.MethodsStable adult dialysis patients for whom CH therapy was planned were included. Patients for whom CH therapy was not planned were simultaneously included as the control group.ResultsThe CH group (n = 44) showed significantly higher circulating levels of Ca, intact PTH, and whole PTH, before the CH treatment than the control group (n = 112). The Ca, intact PTH, and whole PTH levels decreased along with the CH therapy, and the Ca levels became comparable in the 8th week of treatment and thereafter. The CH group in the 8th week and thereafter showed significantly lower whole/intact PTH ratios than the control group, while the whole/intact PTH ratio was not significantly different between before and during the CH therapy. A multiple regression analysis revealed that the whole/intact PTH ratio was almost constant, but both the serum Ca level and a CH therapy could potentially modify the fixed number. When the whole PTH levels were estimated by intact PTH levels using the relationship between them in the control group, the levels were clearly overestimated in the CH group.ConclusionsAlthough the direct effect of CH on the whole/intact PTH ratio is masked by its hypocalcemic action, we could successfully demonstrate that the ratio in CH users is lower than that in the non-users with comparable levels of serum Ca. Evaluating parathyroid function with intact PTH according to the clinical practice guidelines in patients being treated with CH may lead to significant overestimation and subsequent overtreatment.

Safety and immunogenicity of a recombinant hepatitis B vaccine manufactured by a modified process in renal pre-dialysis and dialysis patients

BackgroundPatients with renal insufficiency are hyporesponsive to vaccination, including to hepatitis B vaccines. A manufacturing process modification for a hepatitis B vaccine (mpHBV) was studied in renal pre-dialysis and dialysis patients. MethodsThis randomized, open-label, multicenter, estimation study enrolled previously unvaccinated, HBV-seronegative adult dialysis and pre-dialysis patients (N=276, median age 72.0 years). At 0, 1, 6, and 8 months, group 1 received a 1mL intramuscular dose of mpHBV (containing 40μg HBsAg) as a single injection, while group 2 received a 1mL intramuscular dose of a licensed hepatitis B vaccine as two injections (each containing 20μg HBsAg; 40μg HBsAg total). Serum antibody to HBsAg (anti-HBs) was measured predose 1, and 1 month postdose 3 and 4. Anti-HBs geometric mean concentration (GMC) and seroprotection rate (SPR, % of subjects with anti-HBs titer ≥10mIU/mL) were estimated at months 7 and 9. ResultsFor group 1, month 7 SPR was 48.5% (49/101, 95% CI: 38.4%, 58.7%); with an additional dose, month 9 SPR increased to 66.7% (66/99, 95% CI: 56.5%, 75.8%). For group 2, month 7 SPR was 57.7% (64/111, 95% CI: 47.9%, 67.0%); with an additional dose, month 9 SPR increased to 69.2% (72/104, 95% CI: 59.4%, 77.9%). group 1 GMCs at months 7 and 9 were 27.5mIU/mL (95% CI: 15.7, 48.0) and 61.7mIU/mL (95% CI: 34.2, 111.5), respectively. group 2 GMCs at months 7 and 9 were 48.7mIU/mL (95% CI: 28.7, 82.7) and 115.8mIU/mL (95% CI: 65.2, 205.5), respectively. There were 22 serious adverse events; none were considered related to study vaccine. ConclusionsBoth formulations were immunogenic in this population but required more vaccinations to reach seroprotective levels than comparable regimens in healthy individuals, as expected. The relatively reduced SPRs seen in this population support the need for routine screening and re-dosing in this population.

Fibroblast growth factor 23 in acute kidney injury.

To review the emerging literature on changes in fibroblast growth factor 23 (FGF23) levels in the setting of acute kidney injury (AKI). Studies suggest that FGF23 levels are elevated in patients with AKI and correlate with increased risk of death or need for dialysis in adults, or prolonged ventilation time and higher fluid gain in children. Animal studies have shown that the cause behind this FGF23 increase is multifactorial and includes increased production in bone and decreased clearance, but not vitamin D or parathyroid hormone (PTH) activated pathways. Interestingly, FGF23 levels are found to be mildly elevated even in hospitalized patients without kidney injury, although this observation may be limited to only c-terminal FGF23 fragments. The prognostic implications of an elevated FGF23 value in patients with AKI need to be confirmed in larger cohorts and evaluated for long-term outcomes such as the development of new chronic kidney disease (CKD) or CKD progression, as well as cardiovascular disease, similar to the studies of FGF23 in the prevalent CKD population. FGF23 levels are elevated in patients with AKI and are associated with morbidity and mortality in small human studies. Mechanistic work in animals suggests that the elevation is independent of PTH or vitamin D signaling pathways. Much work remains to understand the physiology behind FGF23 elevation and the long-term effects of FGF23 in AKI.

Neighborhood socioeconomic status, race, and mortality in young adult dialysis patients.

Young blacks receiving dialysis have an increased risk of death compared with whites in the United States. Factors influencing this disparity among the young adult dialysis population have not been well explored. Our study examined the relation of neighborhood socioeconomic status (SES) and racial differences in mortality in United States young adults receiving dialysis. We merged US Renal Data System patient-level data from 11,027 black and white patients ages 18-30 years old initiating dialysis between 2006 and 2009 with US Census data to obtain neighborhood poverty information for each patient. We defined low SES neighborhoods as those neighborhoods in U.S. Census zip codes with ≥20% of residents living below the federal poverty level and quantified race differences in mortality risk by level of neighborhood SES. Among patients residing in low SES neighborhoods, blacks had greater mortality than whites after adjusting for baseline demographics, clinical characteristics, rurality, and access to care factors. This difference in mortality between blacks and whites was significantly attenuated in higher SES neighborhoods. In the United States, survival between young adult blacks and whites receiving dialysis differs by neighborhood SES. Additional studies are needed to identify modifiable factors contributing to the greater mortality among young adult black dialysis patients residing in low SES neighborhoods.