Comparative Effectiveness of Dialysis Modality on Laboratory Parameters of Mineral Metabolism.

INTRODUCTION: Chronic kidney disease-mineral and bone disorders (CKD-MBD) are prevalent in patients undergoing maintenance dialysis. Yet, there are limited and mixed evidence on the effects of different dialysis modalities involving longer treatment times or higher frequencies on CKD-MBD markers. METHODS: This cohort study used data from 132,523 incident dialysis patients treated with any of the following modalities: conventional thrice-weekly in-center hemodialysis, nocturnal in-center hemodialysis (NICHD), home hemodialysis (HHD), or peritoneal dialysis (PD) from 2007 to 2011. We used marginal structural models fitted with inverse probability weights to adjust for fixed and time-varying confounding and informative censoring. We estimated the average effects of treatments with different dialysis modalities on time-varying serum concentrations of CKD-MBD markers: albumin-corrected calcium, phosphate, parathyroid hormone (PTH), and alkaline phosphatase (ALP) using pooled linear regression. RESULTS: Most of the cohort were exclusively treated with conventional in-center hemodialysis, while few were ever treated with NICHD or HHD. At the baseline, PD patients had the lowest mean and median values of PTH, while NICHD patients had the highest median values. During follow-up, compared to hemodialysis patients, patients treated with NICHD had lower mean serum PTH (19.8 pg/mL [95% confidence interval: 2.8, 36.8] lower), whereas PD and HHD patients had higher mean PTH (39.7 pg/mL [31.6, 47.8] and 51.2 pg/mL [33.0, 69.3] higher, respectively). Compared to hemodialysis patients, phosphate levels were lower for patients treated with NICHD (0.44 mg/dL [0.37, 0.52] lower), PD (0.15 mg/dL [0.12, 0.19] lower), or HHD (0.33 mg/dL [0.27, 0.40] lower). There were no clinically meaningful associations between dialysis modalities and concentrations of calcium or ALP. CONCLUSION: In incident dialysis patients, compared to treatment with conventional in-center hemodialysis, treatments with other dialysis modalities with longer treatment times or higher frequency were associated with different patterns of serum phosphate and PTH. Given the recent growth in the use of dialysis modalities other than hemodialysis, the associations between the treatment and the CKD-MBD markers warrant additional study.

KDOQI US Commentary on the 2020 ISPD Practice Recommendations for Prescribing High-Quality Goal-Directed Peritoneal Dialysis.

The recently published 2020 International Society for Peritoneal Dialysis (ISPD) practice recommendations regarding prescription of high-quality goal-directed peritoneal dialysis differ fundamentally from previous guidelines that focused on "adequacy" of dialysis. The new ISPD publication emphasizes the need for a person-centered approach with shared decision making between the individual performing peritoneal dialysis and the clinical care team while taking a broader view of the various issues faced by that individual. Cognizant of the lack of strong evidence for the recommendations made, they are labeled as "practice points" rather than being graded numerically. This commentary presents the views of a work group convened by the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) to assess these recommendations and assist clinical providers in the United States in interpreting and implementing them. This will require changes to the current clinical paradigm, including greater resource allocation to allow for enhanced services that provide a more holistic and person-centered assessment of the quality of dialysis delivered.

Vascular access-specific health-related quality of life impacts among hemodialysis patients: qualitative development of the hemodialysis access-related quality of life (HARQ) instrument.

BACKGROUND: End stage kidney disease and hemodialysis dependence are associated with impairments in health-related quality of life (HRQOL), which may be related to vascular access (VA). Few HRQOL measures are VA-specific and none differentiate HRQOL impact by VA type. We developed a VA-targeted HRQOL measure to distinguish the impact of fistulas, grafts and catheters. METHODS: We created an initial item pool based on literature review and then conducted focus groups at 4 US sites with 37 adults and interviews with nine dialysis clinicians about VA's impact on HRQOL. We then drafted the Hemodialysis Access-Related Quality of Life (HARQ) measure and cognitively tested it with 17 hemodialysis patients. Focus group and cognitive interview participants were diverse in age, gender, years on dialysis, and VA. RESULTS: We identified six domains for the HARQ: symptoms, physical functioning, emotional impacts, social and role functioning, sleep, and care-related burdens. Cognitive interviews indicated that items were easily understood and supported content validity. Attributing HRQOL impact to VA as opposed to other hemodialysis burden was challenging for some items. Some items were dropped that were considered redundant by patients, limitations while dressing was added, and reference to VA-specific impact was included for each item. The average Flesch-Kincaid reading grade level for the revised 47-item HARQ was 5.3. CONCLUSIONS: The HARQ features VA-specific content not addressed in other HRQOL measures, making it ideal for comparisons of different VA types and new VA technologies. The psychometric properties of the HARQ will be evaluated in future research.

Impact of Obesity on Modality Longevity, Residual Kidney Function, Peritonitis, and Survival Among Incident Peritoneal Dialysis Patients.

BACKGROUND: The prevalence of severe obesity, often considered a contraindication to peritoneal dialysis (PD), has increased over time. However, mortality has decreased more rapidly in the PD population than the hemodialysis (HD) population in the United States. The association between obesity and clinical outcomes among patients with end-stage kidney disease remains unclear in the current era. STUDY DESIGN: Historical cohort study. SETTING & PARTICIPANTS: 15,573 incident PD patients from a large US dialysis organization (2007-2011). PREDICTOR: Body mass index (BMI). OUTCOMES: Modality longevity, residual renal creatinine clearance, peritonitis, and survival. RESULTS: Higher BMI was significantly associated with shorter time to transfer to HD therapy (P for trend < 0.001), longer time to kidney transplantation (P for trend < 0.001), and, with borderline significance, more frequent peritonitis-related hospitalization (P for trend = 0.05). Compared with lean patients, obese patients had faster declines in residual kidney function (P for trend < 0.001) and consistently achieved lower total Kt/V over time (P for trend < 0.001) despite greater increases in dialysis Kt/V (P for trend < 0.001). There was a U-shaped association between BMI and mortality, with the greatest survival associated with the BMI range of 30 to < 35kg/m2 in the case-mix adjusted model. Compared with matched HD patients, PD patients had lower mortality in the BMI categories of < 25 and 25 to < 35kg/m2 and had equivalent survival in the BMI category ≥ 35kg/m2 (P for interaction = 0.001 [vs < 25 kg/m2]). This attenuation in survival difference among patients with severe obesity was observed only in patients with diabetes, but not those without diabetes. LIMITATIONS: Inability to evaluate causal associations. Potential indication bias. CONCLUSIONS: Whereas obese PD patients had higher risk for complications than nonobese PD patients, their survival was no worse than matched HD patients.

Diurnal and Long-term Variation in Plasma Concentrations and Renal Clearances of Circulating Markers of Kidney Proximal Tubular Secretion.

BACKGROUND: The renal proximal tubule is essential for removing organic solutes and exogenous medications from the circulation. We evaluated diurnal, prandial, and long-term biological variation of 4 candidate endogenous markers of proximal tubular secretion. METHODS: We used LC-MS to measure plasma and urine concentrations of hippurate (HA), cinnamoylglycine (CMG), indoxyl sulfate (IS), and p-cresol sulfate (PCS) in 25 healthy adults. We measured plasma concentrations of secreted solutes at 13 time points over a 24-h period, and again after 2 weeks and 14 weeks of follow-up. We further measured 24-h renal clearances of secreted solutes at baseline, 2 weeks, and 14 weeks. RESULTS: Plasma concentrations of secreted solutes varied over the 24-h baseline period. Diurnal variation was greatest for HA, followed by CMG, IS, and PCS. Plasma concentrations of HA (P = 0.002) and IS (P = 0.02), but not CMG and PCS, increased significantly following meals. Long-term intraindividual biological variation (CVI) in plasma concentrations of secreted solutes over 14 weeks varied from 21.8% for IS to 67.3% for PCS, and exceeded that for plasma creatinine (CVI, 7.1%). Variation in 24-h renal clearances was similar among the secreted solutes [intraindividual variation (CVA+I), 33.6%-47.3%] and was lower using pooled plasma samples from each study visit. CONCLUSIONS: Plasma concentrations of HA, CMG, IS, and PCS fluctuate within individuals throughout the day and over weeks. Renal clearances of these secreted solutes, which serve as estimates of renal proximal tubule secretion, are also subject to intraindividual biological variation that can be improved by additional plasma measurements.

Indication for Dialysis Initiation and Mortality in Patients With Chronic Kidney Failure: A Retrospective Cohort Study.

BACKGROUND: Initiation of maintenance dialysis therapy for patients with chronic kidney failure is a period of high risk for adverse patient outcomes. Whether indications for dialysis therapy initiation are associated with mortality in this population is unknown. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: 461 patients who initiated dialysis therapy (hemodialysis, 437; peritoneal dialysis, 24) from January 1, 2004, through December 31, 2012, and were treated in facilities operated by a single dialysis organization. Follow-up for the primary outcome was through December 31, 2013. PREDICTOR: Clinically documented primary indication for dialysis therapy initiation, as categorized into 4 groups: laboratory evidence of kidney function decline (reference category), uremic symptoms, volume overload or hypertension, and other/unknown. OUTCOMES: All-cause mortality. RESULTS: During a median follow-up of 2.4 years, 183 (40%) patients died. Crude mortality rates were 10.0 (95% CI, 6.8-14.7), 12.7 (95% CI, 10.2-15.7), 21.7 (95% CI, 16.4-28.6), and 12.2 (95% CI, 6.8-14.7) deaths/100 patient-years among patients initiating dialysis therapy primarily for laboratory evidence of kidney function decline, uremic symptoms, volume overload or hypertension, and other/unknown reason, respectively. Following adjustment for demographic variables, coexisting illnesses, and estimated glomerular filtration rate, initiation of dialysis therapy for uremic symptoms, volume overload or hypertension, or other/unknown reasons was associated with 1.12 (95% CI, 0.72-1.77), 1.69 (95% CI, 1.02-2.80), and 1.28 (95% CI, 0.73-2.26) times higher risk, respectively, for subsequent mortality compared to initiation for laboratory evidence of kidney function decline. LIMITATIONS: Possibility of residual confounding by unmeasured variables; reliance on clinical documentation to ascertain exposure. CONCLUSIONS: Patients initiating dialysis therapy due to volume overload may have increased risk for mortality compared with patients initiating dialysis due to laboratory evidence of kidney function decline. Further studies are needed to identify and test interventions that might reduce this risk.

Effect of Coenzyme Q10 on Biomarkers of Oxidative Stress and Cardiac Function in Hemodialysis Patients: The CoQ10 Biomarker Trial.

BACKGROUND: Oxidative stress is highly prevalent in patients with end-stage renal disease and is linked to excess cardiovascular risk. Identifying therapies that reduce oxidative stress has the potential to improve cardiovascular outcomes in patients undergoing maintenance dialysis. STUDY DESIGN: Placebo-controlled, 3-arm, double-blind, randomized, clinical trial. SETTING & PARTICIPANTS: 65 patients undergoing thrice-weekly maintenance hemodialysis. INTERVENTION: Patients were randomly assigned in a 1:1:1 ratio to receive once-daily coenzyme Q10 (CoQ10; 600 or 1,200mg) or matching placebo for 4 months. OUTCOMES: The primary outcome was plasma oxidative stress, defined as plasma concentration of F2-isoprotanes. Secondary outcomes included levels of plasma isofurans, levels of cardiac biomarkers, predialysis blood pressure, and safety/tolerability. MEASUREMENTS: F2-isoprostanes and isofurans were measured as plasma markers of oxidative stress, and N-terminal pro-brain natriuretic peptide and troponin T were measured as cardiac biomarkers at baseline and 1, 2, and 4 months. RESULTS: Of 80 randomly assigned patients, 15 were excluded due to not completing at least 1 postbaseline study visit and 65 were included in the primary intention-to-treat analysis. No treatment-related major adverse events occurred. Daily treatment with 1,200mg, but not 600mg, of CoQ10 significantly reduced plasma F2-isoprostanes concentrations at 4 months compared to placebo (adjusted mean changes of -10.7 [95% CI, -7.1 to -14.3] pg/mL [P<0.001] and -8.3 [95% CI, -5.5 to -11.0] pg/mL [P=0.1], respectively). There were no significant effects of CoQ10 treatment on levels of plasma isofurans, cardiac biomarkers, or predialysis blood pressures. LIMITATIONS: Study not powered to detect small treatment effects; difference in baseline characteristics among randomized groups. CONCLUSIONS: In patients undergoing maintenance hemodialysis, daily supplementation with 1,200mg of CoQ10 is safe and results in a reduction in plasma concentrations of F2-isoprostanes, a marker of oxidative stress. Future studies are needed to determine whether CoQ10 supplementation improves clinical outcomes for patients undergoing maintenance hemodialysis.

Association between Testosterone and Mortality Risk among U.S. Males Receiving Dialysis.

BACKGROUND: Among the general population, low circulating testosterone levels are associated with higher risk of cardiovascular disease and death. While testosterone deficiency is common in dialysis patients, studies of testosterone and mortality in this population are ambiguous and overlapping. We hypothesized that lower testosterone levels are associated with higher mortality in male dialysis patients. METHODS: We examined a nationally representative cohort of male dialysis patients from a large US dialysis organization who underwent one or more total testosterone measurements from 1/2007 to 12/2011. The association between total testosterone categorized as quartiles and all-cause mortality was studied using Cox models adjusted for expanded case-mix and laboratory covariates. We also examined total testosterone as a continuous predictor of all-cause mortality using restricted cubic splines. RESULTS: Among 624 male dialysis patients, 51% of patients demonstrated testosterone deficiency (total testosterone <300 ng/dL); median (IQR) total testosterone levels were 297 (190-424) ng/mL. In expanded case-mix + laboratory adjusted Cox analyses, we observed a graded association between lower testosterone levels and higher mortality risk (ref: quartile 3): adjusted hazard ratios (95% CI) 2.32 (1.33-4.06), 1.80 (0.99-3.28), and 0.68 (0.32-1.42) for Quartiles 1, 2, and 4, respectively. In adjusted spline analyses, the lower testosterone-higher mortality risk association declined with higher testosterone levels until the value reached a threshold of 400 ng/dL above which risk plateaued. CONCLUSION: Lower testosterone levels were independently associated with higher mortality risk in male dialysis patients. Further studies are needed to determine underlying mechanisms, and whether testosterone replacement ameliorates death risk in this population.

Racial and Ethnic Disparities in Use of and Outcomes with Home Dialysis in the United States.

Home dialysis, which comprises peritoneal dialysis (PD) or home hemodialysis (home HD), offers patients with ESRD greater flexibility and independence. Although ESRD disproportionately affects racial/ethnic minorities, data on disparities in use and outcomes with home dialysis are sparse. We analyzed data of patients who initiated maintenance dialysis between 2007 and 2011 and were admitted to any of 2217 dialysis facilities in 43 states operated by a single large dialysis organization, with follow-up through December 31, 2011 (n =: 162,050, of which 17,791 underwent PD and 2536 underwent home HD for ≥91 days). Every racial/ethnic minority group was significantly less likely to be treated with home dialysis than whites. Among individuals treated with in-center HD or PD, racial/ethnic minorities had a lower risk for death than whites; among individuals undergoing home HD, only blacks had a significantly lower death risk than whites. Blacks undergoing PD or home HD had a higher risk for transfer to in-center HD than their white counterparts, whereas Asians or others undergoing PD had a lower risk than whites undergoing PD. Blacks irrespective of dialysis modality, Hispanics undergoing PD or in-center HD, and Asians and other racial groups undergoing in-center HD were significantly less likely than white counterparts to receive a kidney transplant. In conclusion, there are racial/ethnic disparities in use of and outcomes with home dialysis in the United States. Disparities in kidney transplantation evident for blacks and Hispanics undergoing home dialysis are similar to those with in-center HD. Future studies should identify modifiable causes for these disparities.

Extended-hours hemodialysis is associated with lower mortality risk in patients with end-stage renal disease.

Extended-hours hemodialysis offers substantially longer treatment time compared to conventional hemodialysis schedules and is associated with improved fluid and electrolyte control and favorable cardiac remodeling. However, whether extended-hours hemodialysis improves survival remains unclear. Therefore, we determined the association between extended-hours compared to conventional hemodialysis and the risk of all-cause mortality in a nationally representative cohort of patients initiating maintenance dialysis in the United States from 2007 to 2011. Survival analyses using causal inference modeling with marginal structural models were performed to compare mortality risk among 1206 individuals undergoing thrice weekly extended-hours hemodialysis or 111,707 patients receiving conventional hemodialysis treatments. The average treatment time per session for extended-hours hemodialysis was 399 minutes compared to 211 minutes for conventional therapy. The crude mortality rate with extended-hours hemodialysis was 6.4 deaths per 100 patient-years compared with 14.7 deaths per 100 patient-years for conventional hemodialysis. In the primary analysis, patients treated with extended-hours hemodialysis had a 33% lower adjusted risk of death compared to those who were treated with a conventional regimen (95% confidence interval: 7% to 51%). Additional analyses accounting for analytical assumptions regarding exposure and outcome, facility-level confounders, and prior modality history were similar. Thus, in this large nationally representative cohort, treatment with extended-hours hemodialysis was associated with a lower risk for mortality compared to treatment with conventional in-center therapy. Adequately powered randomized clinical trials comparing extended-hours to conventional hemodialysis are required to confirm these findings.

Serum Magnesium Levels and Hospitalization and Mortality in Incident Peritoneal Dialysis Patients: A Cohort Study.

BACKGROUND: Prior studies have shown the association of low serum magnesium levels with adverse health outcomes in patients undergoing hemodialysis. There is a paucity of such studies in patients undergoing peritoneal dialysis (PD). STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: 10,692 patients treated with PD from January 1, 2007, through December 31, 2011, in facilities operated by a single large dialysis organization in the United States. PREDICTOR: Baseline serum magnesium levels, examined as 5 categories (<1.8, 1.8-<2.0, 2.0-<2.2 [reference], 2.2-<2.4, and ≥2.4mg/dL). OUTCOMES: Time to first hospitalization and time to death using competing-risks regression models. RESULTS: The distribution of baseline serum magnesium levels in the cohort was <1.8mg/dL, 1,928 (18%); 1.8 to <2.0mg/dL, 2,204 (21%); 2.0 to <2.2mg/dL, 2,765 (26%); 2.2 to <2.4mg/dL, 1,765 (16%); and ≥2.4mg/dL, 2,030 (19%). Of 10,692 patients, 6,465 (60%) were hospitalized at least once and 1,392 (13%) died during follow-up (median, 13; IQR, 7-23 months). Baseline serum magnesium level < 1.8mg/dL was associated with higher risk for hospitalization and all-cause mortality after adjustment for demographic and clinical characteristics (adjusted HRs of 1.23 [95% CI, 1.14-1.33] and 1.21 [95% CI, 1.03-1.42], respectively). The higher risk for hospitalization persisted upon adjustment for laboratory variables, whereas that for all-cause mortality was attenuated to a nonsignificant level. The greatest risk for hospitalization was in patients with low serum albumin levels (<3.5g/dL; P for interaction < 0.001). LIMITATIONS: Possibility of residual confounding by unmeasured variables cannot be excluded. CONCLUSIONS: Lower serum magnesium levels may be associated with higher risk for hospitalization in incident PD patients, particularly those with hypoalbuminemia. Additional studies are needed to confirm these findings and investigate whether correction of hypomagnesemia reduces these risks.

Uncorrected and Albumin-Corrected Calcium, Phosphorus, and Mortality in Patients Undergoing Maintenance Dialysis.

Uncorrected serum calcium concentration is the first mineral metabolism metric planned for use as a quality measure in the United States ESRD population. Few studies in patients undergoing either peritoneal dialysis (PD) or hemodialysis (HD) have assessed the association of uncorrected serum calcium concentration with clinical outcomes. We obtained data from 129,076 patients on dialysis (PD, 10,066; HD, 119,010) treated in DaVita, Inc. facilities between July 1, 2001, and June 30, 2006. After adjustment for potential confounders, uncorrected serum calcium <8.5 and ≥10.2 mg/dl were associated with excess mortality in patients on PD or HD (comparison group uncorrected calcium 9.0 to <9.5 mg/dl). Additional adjustment for serum albumin concentration substantially attenuated the all-cause mortality hazard ratios (HRs) associated with uncorrected calcium <8.5 mg/dl (HR, 1.29; 95% confidence interval [95% CI], 1.16 to 1.44 for PD; HR, 1.17; 95% CI, 1.13 to 1.20 for HD) and amplified the HRs associated with calcium ≥10.2 mg/dl (HR, 1.65; 95% CI, 1.42 to 1.91 for PD; HR, 1.59; 95% CI, 1.53 to 1.65 for HD). Albumin-corrected calcium ≥10.2 mg/dl and serum phosphorus ≥6.4 mg/dl were also associated with increased risk for death, irrespective of dialysis modality. In summary, in a large nationally representative cohort of patients on dialysis, abnormalities in markers of mineral metabolism, particularly high concentrations of serum calcium and phosphorus, were associated with increased mortality risk. Additional studies are needed to investigate whether control of hypercalcemia and hyperphosphatemia in patients undergoing dialysis results in improved clinical outcomes.

Association of plasma F2-isoprostanes and isofurans concentrations with erythropoiesis-stimulating agent resistance in maintenance hemodialysis patients.

BACKGROUND: In patients undergoing maintenance hemodialysis (HD), hyporesponsiveness to erythropoiesis stimulating agents (ESAs) is associated with adverse clinical outcomes. Systemic inflammation is highly prevalent in HD patients and is associated with ESA hyporesponsiveness. Oxidative stress is also highly prevalent in HD patients, but no previous study has determined its association with ESA response. This study assessed the association of plasma markers of oxidative stress and inflammation with ESA resistance in patients undergoing maintenance HD. METHODS: We analyzed data from 165 patients enrolled in the Provision of Antioxidant Therapy in Hemodialysis study, a randomized controlled trial evaluating antioxidant therapy in prevalent HD patients. Linear and mixed-effects regression were used to assess the association of baseline and time-averaged high sensitivity F2-isoprostanes, isofurans, C-reactive protein (hsCRP), and interleukin-6 (IL-6) with ESA resistance index (ERI), defined as the weekly weight-adjusted ESA dose divided by blood hemoglobin level. Unadjusted models as well as models adjusted for potential confounders were examined. Predicted changes in ERI per month over study follow-up among baseline biomarker quartiles were also assessed. RESULTS: Patients with time-averaged isofurans in the highest quartile had higher adjusted mean ERI compared with patients in the lowest quartile (ß = 14.9 ng/ml; 95% CI 7.70, 22.2; reference group <0.26 ng/ml). The highest quartiles of hsCRP and IL-6 were also associated with higher adjusted mean ERI (ß = 10.8 mg/l; 95% CI 3.52, 18.1 for hsCRP; ß = 10.2 pg/ml; 95% CI 2.98, 17.5 for IL-6). No significant association of F2-isoprostanes concentrations with ERI was observed. Analyses restricted to baseline exposures and ERI showed similar results. Baseline hsCRP, IL-6, and isofurans concentrations in the highest quartiles were associated with greater predicted change in ERI over study follow-up compared to the lowest quartiles (P = 0.008, P = 0.004, and P = 0.04, respectively). There was no association between baseline F2-isoprostanes quartile and change in ERI. CONCLUSIONS: In conclusion, higher concentrations of isofurans, hsCRP and IL-6, but not F2-isoprostanes, were associated with greater resistance to ESAs in prevalent HD patients. Further research is needed to test whether interventions that successfully decrease oxidative stress and inflammation in patients undergoing maintenance HD improve ESA responsiveness.

A pilot randomized crossover trial assessing the safety and short-term effects of pomegranate supplementation in hemodialysis patients.

OBJECTIVE: Oxidative stress and systemic inflammation are highly prevalent in patients undergoing maintenance hemodialysis (MHD) and are linked to excess cardiovascular risk. This study examined whether short-term supplementation with pomegranate juice and extract is safe and well tolerated by MHD patients. The secondary aim was to assess the effect of pomegranate supplementation on oxidative stress, systemic inflammation, monocyte function, and blood pressure. DESIGN: Prospective, randomized, crossover, pilot clinical trial (NCT01562340). SETTING: The study was conducted from March to October 2012 in outpatient dialysis facilities in the Seattle metropolitan area. SUBJECTS: Twenty-four patients undergoing MHD (men, 64%; mean age, 61 ± 14 years) were randomly assigned to receive pomegranate juice or extract during a 4-week intervention period. After a washout period, all patients received the alternative treatment during a second 4-week intervention period. INTERVENTION: Patients assigned to receive pomegranate juice received 100 mL of juice before each dialysis session. Patients assigned to receive pomegranate extract were given 1,050 mg of extract daily. MAIN OUTCOME MEASURES: The main outcome measures were safety and tolerability of pomegranate juice and extract. Additional secondary outcomes assessed included serum lipids, laboratory biomarkers of inflammation (C-reactive protein and interleukin 6) and oxidative stress (plasma F2 isoprostanes and isofurans), monocyte cytokine production, and predialysis blood pressure. RESULTS: Both pomegranate juice and extract were safe and well tolerated by study participants. Over the study period, neither treatment had a significant effect on lipid profiles, plasma C-reactive protein, interleukin 6, F2-isoprostane or isofuran concentrations, predialysis systolic or diastolic blood pressure nor changed the levels of monocyte cytokine production. CONCLUSIONS: Both pomegranate juice and extract are safe and well tolerated by patients undergoing MHD but do not influence markers of inflammation or oxidative stress nor affect predialysis blood pressure.

The changing landscape of home dialysis in the United States.

PURPOSE OF REVIEW: To discuss the changing landscape of home dialysis in the United States over the past decade, including recent research on clinical outcomes in patient undergoing peritoneal dialysis and home hemodialysis, and to describe the impact of recent payment reforms for patients with end-stage renal disease. RECENT FINDINGS: Accumulating evidence supports the conclusion that clinical outcomes for patients treated with peritoneal dialysis or home hemodialysis are as good as or better than for patients treated with conventional in-center hemodialysis. The recent implementation of the Medicare-expanded prospective payment system for the care of end-stage renal disease patients has resulted in substantial growth in the utilization of peritoneal dialysis in the United States. Utilization of home hemodialysis has also grown, but the contribution of the expanded prospective payment system to this growth is less certain. SUMMARY: Home dialysis, including peritoneal dialysis and home hemodialysis, represents an important alternative to in-center hemodialysis that is effective and patient-centered. Over the coming decade, the growth in the number of end-stage renal disease patient treated with home dialysis modalities should prompt further comparative and cost-effectiveness research, increased attention to racial and ethnic disparities, and investments in home dialysis education for both patients and providers. VIDEO ABSTRACT: http://links.lww.com/CONH/A13.

From Home to Wearable Hemodialysis: Barriers, Progress, and Opportunities.

Although the past two decades have seen substantial proportional growth of home hemodialysis in the United States, the absolute number of patients treated with home hemodialysis remains small. Currently available stationary hemodialysis devices for use in the home have inherent limitations that represent barriers for more widespread adoption by a larger proportion of individuals with kidney failure. These limitations include device weight and bulk, ergonomics considerations, technical complexity, vascular access challenges, and limited remote patient monitoring. Recent years have witnessed a resurgence in research and development of prototype wearable kidney replacement devices incorporating innovations in miniaturization, new biomaterials, and new methods for toxin clearance and dialysate regeneration. Recent work has built on five decades of incremental innovation in wearable dialysis concepts and prototypes, starting from the work by Kolff in the 1970s. Wearable dialysis devices that successfully overcome key persistent barriers to successful development and adoption of these technologies will radically reshape the landscape of kidney replacement therapies and have the potential to dramatically improve the lives of individuals living with kidney failure.

Evaluation and Measurement Properties of a Patient-Reported Experience Measure for Home Dialysis.

BACKGROUND: No previously validated patient-reported experience measures exist for use among patients undergoing home dialysis. We tested the Home Dialysis Care Experience survey, a newly developed 26-item experience measure, among patients from 30 dialysis facilities in the United States. METHODS: Using mail and telephone survey modalities, we approached 1372 patients treated with peritoneal dialysis or home hemodialysis for participation. Using the results from completed surveys, we evaluated item calibration by assessing item floor and ceiling effects. We tested three sets of composite scores and used factor analysis to assess model fit for each. We evaluated associations of composite scores with global ratings and separately with patient and dialysis facility characteristics. Finally, we measured test-retest reliability in patients who completed the survey at two separate time points. RESULTS: Overall, 495 eligible patients completed at least one survey (response rate 36%). Of these, 49 completed the survey in Spanish and 61 completed a second survey within 30 days. We did not detect significant floor or ceiling effects, except for one item that demonstrated >90% responses at the top response option. Analyses supported one 12-item composite scale with high internal consistency reliability: Quality of Home Dialysis Care and Operations (Cronbach alpha=0.85). This scale strongly correlated with overall staff rating ( r =0.73) and overall center rating ( r =0.70). Patient demographic and dialysis facility characteristics were not consistently associated with composite scale scores or overall staff or center ratings. Intraclass correlation coefficients in the test-retest population were 0.74 for the Quality scale, 0.88 for overall staff rating, and 0.90 for overall center rating. CONCLUSIONS: The Home Dialysis Care Experience survey is a 26-item measure that includes one composite scale and two global rating scores and is an informative tool to evaluate patient experience of care for home dialysis.

Gout Prevalence, Practice Patterns, and Associations with Outcomes in North American Dialysis Patients.

INTRODUCTION: Gout occurs frequently in patients with kidney disease and can lead to a significant burden on quality of life. Gout prevalence, and its association with outcomes in hemodialysis (HD) and peritoneal dialysis (PD) populations located in North America, is unknown. METHODS: We used data from North America cohorts of 70,297 HD patients (DOPPS, 2012-2020) and 5117 PD patients (PDOPPS, 2014-2020). We used three definitions of gout for this analysis: (1) having an active prescription for colchicine or febuxostat; (2) having an active prescription for colchicine, febuxostat, or allopurinol; or (3) having an active prescription for colchicine, febuxostat, or allopurinol, or prior diagnosis of gout. Propensity score matching was used to compare outcomes among patients with versus without gout. Outcomes included erythropoietin resistance index (ERI=erythropoiesis stimulating agent dose per week/(hemoglobin×weight)), all-cause mortality, hospitalization, and patient-reported outcomes (PROs). RESULTS: The gout prevalence was 13% in HD and 21% in PD; it was highest among incident dialysis patients. Description of previous history of gout was rare, and identification of gout defined by colchicine (2%-3%) or febuxostat (1%) prescription was less frequent than by allopurinol (9%-12%). Both HD and PD patients with gout (versus no gout) were older, were more likely male, had higher body mass index, and had higher prevalence of cardiovascular comorbidities. About half of patients with a gout history were prescribed urate-lowering therapy. After propensity score matching, mean ERI was 3%-6% higher for gout versus non-gout patients while there was minimal evidence of association with clinical outcomes or PROs. CONCLUSION: In a large cohort of PD and HD patients in North America, we found that gout occurs frequently and is likely under-reported. Gout was not associated with adverse clinical or PROs.

Patient-reported outcomes in hemodialysis vascular access: A call to action.

While access-related dysfunction is a clear driver of clinical outcomes and costs, the full impact of vascular access dysfunction on patient experience and quality of life is not fully characterized in the literature. One way to more comprehensively characterize the patient experience from the patient perspective is through patient reported outcomes (PROs). However, the limited implementation of PROs in clinical trials, patient registries, quality measurement, and other research settings has significantly constrained the patient voice in evaluation of vascular access outcomes and vascular access decision-making. To address these issues, the Kidney Health Initiative, a public-private partnership between the American Society of Nephrology and the U.S. Food and Drug Administration, assembled an interdisciplinary workgroup to enhance uptake of access-related PROs with the aims of: (1) reviewing the domains of HRQOL that are affected by vascular access, collect information on existing instruments that measure access-specific HRQOL in hemodialysis, and identify gaps in existing measures; (2) identifying and critically assessing barriers to widespread use of access-specific PRO measures; and (3) defining initiatives to overcome barriers and make recommendations for strategies to improve the use and utility of access-specific PRO measures. A consensus group process identified potential barriers to use of PRO measures in six categories: (1) PRO misperceptions, (2) patient factors, (3) regulators and payers, (4) instrument factors, (5) study design, and (6) physicians. The workgroup provided recommendations for actions to promote the widespread utilization of vascular access-related PRO measures in five categories: (1) development of vascular access-specific PRO measures, (2) ensuring comprehensive assessment when using vascular access PRO measures, (3) ensuring accessibility and applicability of vascular access PRO measures to all end stage kidney disease populations, (4) establishing universal guidelines and accepted vascular access PRO measures, and (5) engaging stakeholders across all facets.

Development and Content Validity of a Patient-Reported Experience Measure for Home Dialysis.

BACKGROUND AND OBJECTIVES: The population of patients with kidney failure in the United States using home dialysis modalities is growing rapidly. Unlike for in-center hemodialysis, there is no patient-reported experience measure for assessment of patient experience of care for peritoneal dialysis or home hemodialysis. We sought to develop and establish content validity of a patient-reported experience measure for patients undergoing home dialysis using a mixed methods multiple stakeholder approach. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a structured literature review, followed by concept elicitation focus groups and interviews among 65 participants, including 21 patients on home dialysis, 33 home dialysis nurses, three patient care partners, and eight nephrologists. We generated a list of candidate items for possible measure inclusion and conducted a national prioritization exercise among 91 patients on home dialysis and 39 providers using a web-based platform. We drafted the Home Dialysis Care Experience instrument and conducted cognitive debriefing interviews to evaluate item interpretability, order, and structure. We iteratively refined the measure on the basis of interview findings. RESULTS: The literature review and concept elicitation phases supported 15 domains of home dialysis care experience in six areas: communication and education of patients, concern and helpfulness of the care team, proficiency of the care team, patient-centered care, care coordination, and amenities and environment. Focus groups results showed that domains of highest importance for measure inclusion were patient education and communication, care coordination, and personalization of care. Prioritization exercise results confirmed focus group findings. Cognitive debriefing indicated that the final measure was easily understood and supported content validity. CONCLUSIONS: The Home Dialysis Care Experience instrument is a 26-item patient-reported experience measure for use in peritoneal dialysis and home hemodialysis. The Home Dialysis Care Experience instrument represents the first rigorously developed and content-valid English-language instrument for assessment of patient-reported experience of care in home dialysis.