Patient-Centered Home Hemodialysis: Approaches and Prescription

Writing a home hemodialysis (HD) prescription is a complex, multifactorial process that requires the incorporation of patient values, preferences, and lifestyle. Knowledge of the different options available for home HD modality (conventional, nocturnal, short daily, and alternate nightly) is also important when customizing a prescription. Finally, an understanding of the different home HD machines currently approved for use at home and their different attributes and limitations helps guide providers when formulating their prescriptions. In this review article, we set out to address these different aspects to help guide providers in providing a patient-centered home HD approach.

Age- and Race-Specific Changes in ESKD Incidence over Four Decades

SIGNIFICANCE STATEMENT

ESKD incidence has changed substantially in the past four decades, but differences by age and race have been unexplored. Using data from the United States Renal Data System, we found that ESKD incidence rose for Black and White teenagers, adults, and older adults for two decades beginning in 1980. Growth in incidence slowed for most groups by 1993, and by 2006, the annual percent change (APC) in ESKD incidence had declined for all groups, except White adults, for whom rates continued to rise. By 2019, ESKD incidence among Black and White adolescents nearly returned to 1980 levels, but no other group achieved that degree of improvement. Nonetheless, the ESKD incidence rate among Black American patients exceeds that of White patients in every age group. Distinct patterns in ESKD incidence among patients of different age, sex, and racial groups are shown. These findings could reflect changes in dialysis acceptance rates, access to preventive health care, incidence of diabetes mellitus, implementation of evidence-based guidelines for treatment of CKD, or other unrecognized factors. There may be population-specific opportunities to change the growth of the US ESKD population and address current racial disparities.

BACKGROUND

Substantial changes in ESKD incidence over four decades among Black and White Americans of different ages have been incompletely explored.

METHODS

We analyzed United States Renal Data System data from 1980 to 2019 to determine ESKD incidence trends among Black and White adolescent (13-17 years), adult (18-64 years), and older adult (≥65) populations. We used the National Cancer Institute Joinpoint Regression Program to estimate annual percent change (APC) in ESKD incidence and to define points in time where a statistically significant change in APC slope occurred for each group.

RESULTS

ESKD incidence rose after 1980 for all groups, although the trends differed ( P < 0.001). Growth in incidence slowed for most by 1993, and by 2006, the APC in ESKD incidence had declined for all groups, except White adults, for whom rates continued to rise ( P < 0.05). By 2019, ESKD incidence among Black and White adolescents nearly returned to 1980 levels, but no other group achieved that degree of improvement. Nonetheless, the ESKD incidence among Black American patients exceeds that of White patients in every age group.

CONCLUSIONS

Distinct patterns in ESKD incidence among patients of different age, sex, and racial groups are shown. These findings could reflect changes in dialysis acceptance rates, access to preventive health care, incidence of diabetes mellitus, implementation of evidence-based guidelines for treatment of CKD, or other unrecognized factors.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2024_03_13_ASN0000000000000310.mp3.

Trust, Multidimensional Health Literacy, and Medication Adherence among Patients Undergoing Long-Term Hemodialysis

BACKGROUND

Basic health literacy and trust in physicians can influence medication adherence in patients receiving dialysis. However, how high-order health literacy is associated with medication adherence and how trust in physicians mediates this association remain unclear. We assessed the inter-relationships between health literacy, trust in physicians, and medication adherence. We investigated the mediating role of trust in physicians in the relationship between health literacy and medication adherence.

METHODS

This multicenter cross-sectional study included Japanese adults receiving outpatient hemodialysis at six dialysis centers. Multidimensional health literacy was measured using the 14-item Functional, Communicative, and Critical Health Literacy scale. Trust in physicians was measured using the five-item Wake Forest Physician Trust scale. Medication adherence was measured using the 12-item Adherence Starts with Knowledge scale. A series of general linear models were created to analyze the associations between health literacy and Adherence Starts Knowledge scores with and without trust in physicians. Mediation analysis was performed to determine whether trust in physicians mediated this association.

RESULTS

In total, 455 patients were analyzed. Higher functional and communicative health literacies were associated with less adherence difficulties (per 1-point higher: -1.79 [95% confidence interval (CI): -2.59 to -0.99] and -2.21 [95% CI: -3.45 to -0.96], respectively), whereas higher critical health literacy was associated with greater adherence difficulties (per 1-point higher: 1.69 [95% CI: 0.44 to 2.94]). After controlling for trust in physicians, the magnitude of the association between health literacies and medication adherence decreased. Trust in physicians partially mediated the association between functional or communicative health literacy and medication adherence (especially beliefs) and completely mediated the association between critical health literacy and medication adherence (especially behaviors).

CONCLUSIONS

Functional and communicative health literacies were positively associated with medication adherence, whereas critical health literacy was negatively associated with it. Each association was mediated by trust in physicians.

Peritoneal Dialysis (PD) Patient and Nurse Preferences around Novel and Standard Automated PD Device Features

Key Points

Adoption and extended time on peritoneal dialysis require patient input across a spectrum of needs, including automated PD (APD) device usability features that are less intimidating to patients and enable lifestyle advantages. Analysis of APD features critical to patients align with patient priorities identified in Standardized Outcomes in NephroloGy-PD: shorter setup time, mobility within the home, near silent operation, and modified APD size/orientation.

Background

Despite offering greater lifestyle benefits to patients with ESKD, adoption of peritoneal dialysis (PD) remains low globally, particularly among minorities and the socioeconomically disadvantaged. While automated PD (APD) affords a high potential for reducing the burden of KRT, understanding patient preferences is critical to guiding development of new and improved APD devices to better accommodate use in their daily lives.

Methods

A quantitative cross-sectional survey study was performed using adaptive conjoint analysis to quantify APD feature preferences among patients on PD, PD Registered Nurses (RNs), and non-PD patients to ascertain the relative importance of eight specific cycler attributes, including portability, noise, setup time, device size, setup directions, battery power, consumables, and PD RN control (PD RNs only), each with 2–3 descriptive feature levels.

Results

Forty-two patients on PD, 24 non-PD patients, and 52 PD RNs were surveyed. Preference shares spanned nearly the entire range from 0% to 100%, indicating strong preference discrimination. For all groups, “Portability in the Home,” “Noise Level,” and “Setup Time” were the most important features. Patients on PD gave highest priority to these features compared with other study participants, plausibly as features enabling improved lifestyle. A simulated “coat rack” style cycler with extended battery power that was easy to move in the home, silent, required only 10-minute setup, and had a fully animated instruction screen was preferred by all groups >90% compared with features present in existing cyclers.

Conclusions

Addressing APD cycler technical and therapy-related issues to improve usability, comfort, and convenience within the home may affect PD uptake and retention. Attention and priority must be given to patient-centric APD cycler design directed at including features that improve quality of life for the device end user.

Delivering Person-Centered Peritoneal Dialysis

Peritoneal dialysis (PD) enables people to have a home-based therapy, permitting greater autonomy for individuals along with enhanced treatment satisfaction compared with in-center dialysis care. The burden of treatment on PD, however, remains considerable and underpins the need for person-centered care. This reflects the need to address the patient as a person with needs and preferences beyond just the medical perspective. Shared decision making is central to the recent International Society for Peritoneal Dialysis recommendations for prescribing PD, balancing the potential benefits of PD on patient well-being with the burden associated with treatment. This review considers the role of high-quality goal-directed prescribing, incremental dialysis, and remote patient monitoring in reducing the burden of dialysis, including an approach to implementing incremental PD. Although patient-related outcomes are important in assessing the response to treatment and, particularly life participation, the corollary of dialysis burden, there are no clear routes to the clinical implementation of patient-related outcome measures. Delivering person-centered care is dependent on treating people both as individuals and as equal partners in their care.

The Improved Kidney Risk Score in ANCA-Associated Vasculitis for Clinical Practice and Trials

SIGNIFICANCE STATEMENT

Reliable prediction tools are needed to personalize treatment in ANCA-associated GN. More than 1500 patients were collated in an international longitudinal study to revise the ANCA kidney risk score. The score showed satisfactory performance, mimicking the original study (Harrell's C=0.779). In the development cohort of 959 patients, no additional parameters aiding the tool were detected, but replacing the GFR with creatinine identified an additional cutoff. The parameter interstitial fibrosis and tubular atrophy was modified to allow wider access, risk points were reweighted, and a fourth risk group was created, improving predictive ability (C=0.831). In the validation, the new model performed similarly well with excellent calibration and discrimination ( n =480, C=0.821). The revised score optimizes prognostication for clinical practice and trials.

BACKGROUND

Reliable prediction tools are needed to personalize treatment in ANCA-associated GN. A retrospective international longitudinal cohort was collated to revise the ANCA renal risk score.

METHODS

The primary end point was ESKD with patients censored at last follow-up. Cox proportional hazards were used to reweight risk factors. Kaplan-Meier curves, Harrell's C statistic, receiver operating characteristics, and calibration plots were used to assess model performance.

RESULTS

Of 1591 patients, 1439 were included in the final analyses, 2:1 randomly allocated per center to development and validation cohorts (52% male, median age 64 years). In the development cohort ( n =959), the ANCA renal risk score was validated and calibrated, and parameters were reinvestigated modifying interstitial fibrosis and tubular atrophy allowing semiquantitative reporting. An additional cutoff for kidney function (K) was identified, and serum creatinine replaced GFR (K0: <250 µ mol/L=0, K1: 250-450 µ mol/L=4, K2: >450 µ mol/L=11 points). The risk points for the percentage of normal glomeruli (N) and interstitial fibrosis and tubular atrophy (T) were reweighted (N0: >25%=0, N1: 10%-25%=4, N2: <10%=7, T0: none/mild or <25%=0, T1: ≥ mild-moderate or ≥25%=3 points), and four risk groups created: low (0-4 points), moderate (5-11), high (12-18), and very high (21). Discrimination was C=0.831, and the 3-year kidney survival was 96%, 79%, 54%, and 19%, respectively. The revised score performed similarly well in the validation cohort with excellent calibration and discrimination ( n =480, C=0.821).

CONCLUSIONS

The updated score optimizes clinicopathologic prognostication for clinical practice and trials.

A National Survey of Conservative Kidney Management Practices for Patients Who Forgo RRT

Key Points

In the largest survey of US nephrology providers on conservative kidney management (CKM), most reported limited experience with CKM and varied approaches and local resources to provide CKM. There is need to enhance provider training and surveillance of CKM practices and to develop models of CKM that optimize care delivery and outcomes for these patients.

Background

Clinical practice guidelines advocate for conservative kidney management (CKM), a planned, holistic, patient-centered approach to caring for patients who forgo initiation of RRT. Little is known about the extent to which current care practices meet these expectations.

Methods

We conducted a cross-sectional survey of a national sample of nephrology providers recruited through US professional societies between March and July 2022 and inquired about their experiences with caring for patients who forgo RRT and their capacity to provide CKM.

Results

Overall, 203 nephrology providers (age 47±12 years, 53.2% White, 66.0% female), of which 49.8% were nephrologists and 50.2% advanced practice providers, completed the survey. Most (70.3%) reported that <10% of their practice comprised patients who had forgone RRT. Most indicated that they always or often provided symptom management (81.8%), multidisciplinary care (68.0%), tools to support shared decision making about treatment of advanced kidney disease (66.3%), and psychological support (52.2%) to patients who forgo RRT, while less than half reported that they always or often provided staff training on the care of these patients (47.8%) and spiritual support (41.4%). Most providers reported always or often working with primary care (72.9%), palliative medicine (68.8%), hospice (62.6%), social work (58.1%), and dietitian (50.7%) services to support these patients, while only a minority indicated that they always or often offered chaplaincy (23.2%), physical and/or occupational therapy (22.8%), psychology or psychiatry (31.5%), and geriatric medicine (28.1%).

Conclusions

Many nephrology providers have limited experience with caring for patients who forgo RRT. Our findings highlight opportunities to optimize comprehensive CKM care for these patients.

Strategies to Guide Preemptive Waitlisting and Equity in Waittime Accrual by Race/Ethnicity

BACKGROUND

Use of eGFR to determine preemptive waitlisting eligibility may contribute to racial/ethnic disparities in access to waitlisting, which can only occur when the eGFR falls to ≤20 ml/min per 1.73 m 2 . Use of an alternative risk-based strategy for waitlisting may reduce these inequities ( e.g. , a kidney failure risk equation [KFRE] estimated 2-year risk of kidney failure) rather than the standard eGFR threshold for determining waitlist eligibility. Our objective was to model the amount of preemptive waittime that could be accrued by race and ethnicity, applying two different strategies to determine waitlist eligibility.

METHODS

Using electronic health record data, linear mixed models were used to compare racial/ethnic differences in preemptive waittime that could be accrued using two strategies: estimating the time between an eGFR ≤20 and 5 ml/min per 1.73 m 2 versus time between a 25% 2-year predicted risk of kidney failure (using the KFRE, which incorporates age, sex, albuminuria, and eGFR to provide kidney failure risk estimation) and eGFR of 5 ml/min per 1.73 m 2 .

RESULTS

Among 1290 adults with CKD stages 4-5, using the Chronic Kidney Disease Epidemiology Collaboration equation yielded shorter preemptive waittime between an eGFR of 20 and 5 ml/min per 1.73 m 2 in Black (-6.8 months; 95% confidence interval [CI], -11.7 to -1.9), Hispanic (-10.2 months; -15.3 to -5.1), and Asian/Pacific Islander (-10.3 months; 95% CI, -15.3 to -5.4) patients compared with non-Hispanic White patients. Use of a KFRE threshold to determine waittime yielded smaller differences by race and ethnicity than observed when using a single eGFR threshold, with shorter time still noted for Black (-2.5 months; 95% CI, -7.8 to 2.7), Hispanic (-4.8 months; 95% CI, -10.3 to 0.6), and Asian/Pacific Islander (-5.4 months; -10.7 to -0.1) individuals compared with non-Hispanic White individuals, but findings only met statistical significance criteria in Asian/Pacific Islander individuals. When we compared potential waittime availability using a KFRE versus eGFR threshold, use of the KFRE yielded more equity in waittime for Black ( P = 0.02), Hispanic ( P = 0.002), and Asian/Pacific Islander ( P = 0.002) patients.

CONCLUSIONS

Use of a risk-based strategy was associated with greater racial equity in waittime accrual compared with use of a standard single eGFR threshold to determine eligibility for preemptive waitlisting.

International Variability in the Epidemiology, Management, and Outcomes of CKD and ESKD: A Systematic Review

Key Points

There is dramatic global variability in the prevalence of ESKD. Higher per capita health care spending in each country is associated with increased delivery of care for ESKD.

Background

Approaches to treating ESKD may vary internationally on the basis of the availability of care and other factors. We performed a systematic review to understand the international variability in ESKD epidemiology, management, and outcomes.

Methods

We systematically searched PubMed for population-based studies of CKD and ESKD epidemiology and management. Population-level data from 23 predesignated nations were eligible for inclusion if they pertained to people receiving dialysis or kidney transplant for ESKD. When available, government websites were used to identify and extract data from relevant kidney registries. Measures gathered included those related to the prevalence and mortality of ESKD; the availability of nephrologists; per capita health care expenditures; and use of erythropoietin-stimulating agents.

Results

We obtained data from the United States; seven nations in Eastern Europe; four each in Western Europe, Latin America, and Africa; and three in Asia. The documented prevalence of ESKD per million population varied from a high of 3600 (Malaysia) to a low of 67 (Senegal). The annual mortality associated with ESKD varied from 31% (Ethiopia and Senegal) to 10% (the United Kingdom). Nephrologist availability per million population varied from 40 (Japan) to <1 (South Africa) and was associated with per capita health care expenditures.

Conclusions

The delivery of kidney care related to ESKD varies widely among countries. Higher per capita health care spending is associated with increased delivery of kidney care. However, in part because documentation of kidney disease varies widely, it is difficult to determine how outcomes related to ESKD may vary across nations.

The Clinical and Pathological Characteristics of Patients with Oxalate Nephropathy

Key Points

Oxalate nephropathy is an underrecognized cause of CKD and ESKD We present one of the largest native oxalate nephropathy cohorts to date from a tertiary care institution in the United States Oxalate nephropathy has multiple etiologies and given its clinical course and poor prognosis, attention must be paid to screening for risk factors to guide prompt diagnosis and management

Background

Oxalate nephropathy (ON) is characterized by deposition of calcium oxalate crystals in the kidney and is commonly under-recognized. Causes of ON include primary hyperoxaluria, enteric hyperoxaluria, and ingestion of excess oxalate or its precursors.

Methods

We report the clinical and pathological characteristics of one of the largest series of native kidney ON to date, from January 2015 to March 2023 at the Cleveland Clinic.

Results

We identified 60 native biopsies with oxalate deposits and excluded patients with clinically insignificant biopsies (n =12) or lack of data (n =17). Thirty-one patients with native ON were described. The mean age at diagnosis was 66.2 years (±12.1), and 58.1% were female. 87.1% had hypertension, 58.1% had diabetes, 42% had nephrolithiasis, and 77.4% had underlying CKD, with a mean baseline creatinine of 1.8 mg/dl ±1.3.

The mean creatinine at biopsy was 5.2 mg/dl ±1.7. Kidney biopsies showed abundant calcium oxalate crystal deposits, and 27 of 31 biopsies had additional diagnoses, the most common of which were acute tubular injury n =17 (54.8%) and diabetic glomerulosclerosis n =7 (22.6%). Severe and moderate interstitial fibrosis was present in 38.7% (n =12) and 51.6% (n =16) of biopsies, respectively. Ten had a single etiology of ON, ten had a multifactorial etiology (both enteric hyperoxaluria and high precursor intake), and 11 had an unclear etiology. Notably, only seven patients had a history of gastric bypass.

The mean duration of follow-up was 26.8 months, and 26 patients had follow-up data >1 year. Of these, 21 required dialysis, and five were dialysis-free at presentation. Five of the 26 were deceased at 1 year, with 12 patients (38.7%) deceased at last follow-up. Seventeen patients received targeted management, while nine patients did not receive targeted treatment, and all nine required hemodialysis. More patients (31.6%) had vitamin C intake after the coronavirus disease 2019 pandemic (2020–2023) versus 16.7% before 2020.

Conclusions

ON presents as AKI or acute on CKD. The prognosis is poor with most patients requiring dialysis at presentation with high morbidity and mortality. Clinicians need to be aware of the risk factors associated with ON to aid prompt diagnosis and management.

Podcast

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/K360/2024_01_26_KID0000000000000340.mp3

Transplantation, Waitlist Status, and County Indices of Economic Health in West Virginia

Key Points

Patients with ESKD coming from impoverished counties are less likely to be waitlisted or transplanted. Insurance status modified the relationship between county poverty rates and waitlisting/transplant.

Background

Kidney transplantation is the optimal treatment for patients with ESKD. Given lower rates of kidney transplant in West Virginia (WV), we searched for potential predictors, focusing on the indices of economic health.

Methods

Data on the initiation of RRT, being waitlisted for, and receiving a kidney transplant between 1965 and 2020 were collected from United States Renal Data System. Data on county poverty rate (PR) and economic distress were collected from the Appalachian Regional Commission.

Results

Of the 23,055 WV patients identified, 2999 (13%) were transplanted compared with 514,050 (15.3%) for the rest of the United States (P < 0.001). Patients who never received a kidney transplant were from counties with higher PRs (17.95%) compared with transplanted patients (17.44%; P < 0.001). Waitlisted patients (2,375) came from counties with lower PRs than those who were never waitlisted (17.48 versus 17.94%; P < 0.001). Waitlisted patients were less likely to be from distressed or at-risk counties (32 versus 34.3%; P = 0.05) than patients who were never waitlisted. In multivariable logistic regression, county PR remained an independent predictor of being transplanted (odds ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P = 0.008) or waitlisted (odds ratio, 0.9; 95% confidence interval, 0.84 to 0.96; P = 0.001) per 5% increase in PR after adjusting for age, sex, body mass index, alcohol use, functional status, and comorbid medical conditions. Group/employer health insurance seemed to modify the relationship between PR and waitlist, where PR remained an independent predictor of waitlisting among patients with insurance.

Conclusions

Waitlisted patients and transplant recipients from WV were more likely to hail from counties with lower PRs and those in better economic health.

Symptom Trajectories in the Electronic Health Record during the Transition to Maintenance Dialysis

How symptoms recorded in the electronic health record change during the transition to dialysis has not been fully explored. We used the Optum deidentified Integrated Claims-Clinical dataset to identify individuals with CKD stages 4 or 5 who transitioned to dialysis. We searched structured data elements from clinical notes, identified by natural language processing, for symptoms recorded across weekly intervals in the 6 months before and after dialysis initiation and estimated changes in the odds of a symptom being recorded with an interrupted time series analysis using segmented logistic regression. The cohort comprised 728 individuals (aged 68±13 years, 44% women, 56% White, 30% Black). Before dialysis initiation, 83% were recorded as having pain, 68% fatigue/weakness, 66% shortness of breath, 61% nausea/vomiting, and 37% difficulty concentrating. Before dialysis initiation, odds of pain being recorded increased (slope: odds ratio [OR] 1.02 per week, 95% confidence interval [CI], 1.01 to 1.03); initiation was associated with a decrease (intercept change: OR 0.70, 95% CI, 0.59 to 0.82). After initiation, odds of pain were unchanged (postdialysis slope: OR 1.00 per week, 95% CI, 0.99 to 1.01), although this represented an improved trajectory relative to the predialysis period (change in slope: OR 0.98 per week, 95% CI, 0.96 to 0.99). For fatigue/weakness, odds increased before initiation (OR 1.03 per week, 95% CI, 1.02 to 1.04) but decreased on initiation (OR 0.62, 95% CI, 0.51 to 0.75) and thereafter (OR 0.98 per week, 95% CI, 0.97 to 0.99), representing a reduction in slope (OR 0.95 per week, 95% CI, 0.94 to 0.97). Patterns for shortness of breath, nausea/vomiting, and difficulty concentrating were similar to those of pain. Thus, the odds of five key symptoms being recorded in the electronic health record increased over time in the 6 months before dialysis initiation, decreased immediately on initiation, and, generally, remained unchanged in the 6 months thereafter.

Self-Management Interventions for Facilitating Life Participation for Persons with Kidney Failure: A Systematic Review

BACKGROUND

For persons with kidney failure, life participation is a critically important outcome, strongly linked to quality of life and mortality. To support patients' self-management abilities, three domains are typically emphasized: medical management, emotional management, and management of everyday life ( i.e. , role management). Although role management is strongly linked to life participation, there is currently limited research on interventions designed to support it. We explored existing self-management interventions that aim to support everyday life functioning, rather than only medical management.

METHODS

In this systematic review and qualitative meta-synthesis, we searched MEDLINE, Embase, CINAHL, PsycINFO, Web of Science, and CENTRAL up to April 2022 for interventional studies involving self-management interventions designed, at least partly, to support management of everyday life. The guidelines by Sandelowski and Barosso were used to analyze and synthesize the results. A taxonomy of everyday self-management strategies was used to further explore intervention content. Study quality was assessed using the Cochrane Collaboration risk-of-bias tools. Evidence of effectiveness was summarized, and a meta-analysis of eligible outcomes was conducted.

RESULTS

Of 22,667 records, 53 studies were included in the meta-synthesis. Most self-management interventions focused on medical management. Included interventions involved strategies to support eight domains: Activities of daily living, Work and school life, Meaningful occupations, Leisure activities, Mobility and travel, Interpersonal relationships, Role functioning, and Social participation. Major interventions focused on providing education, skill training, counseling, and cognitive behavioral therapy. Evidence of effectiveness was reported across a wide range of patient-reported outcomes, including (health-related) quality of life, depression, and self-efficacy. Studies were geographically concentrated and were of moderate to low quality.

CONCLUSIONS

Despite its well-recognized importance, research on interventions to improve life participation mostly consisted of pilot and feasibility studies and studies of low quality. Interventions were reported heterogeneously, limiting comparability, and were restricted to specific regions and cultures, limiting generalizability.

Gender Disparities in Nephrology Trials: A Meta-Analysis of Enrollment Trends between 2000 and 2021

Key Points

Women are under-represented in high-impact nephrology trials. Trends remain consistent over the past 20 years and on the basis of target condition. Addressing the imbalanced enrollment of women in trials could improve disparities in care and outcomes of kidney disease.

Background

Gender disparities in the incidence and complications of kidney diseases are well described. However, analysis to elucidate gender disparities in enrollment in nephrology randomized clinical trials (RCTs) has not been performed.

Methods

We performed a systematic review and meta-analysis of high-impact nephrology RCTs published between 2000 and 2021. We included RCTs enrolling participants aged 18 years and older in the following categories: (1 ) CKD, (2 ) AKI, (3 ) GN, (4 ) maintenance dialysis, and (5 ) kidney transplantation. We summarized trial characteristics according to reporting and enrollment of participants, enrollment site, publication year, trial category, and intervention type. Outcomes of interest include the proportion of enrolled male and female participants overall and according to trial category. In addition, we compared enrollment trends in the United States and globally to estimates of kidney disease prevalence.

Results

Most qualifying trials (373/380, 98%) reported the distribution of male and female participants. Enrollment was imbalanced overall with male participants accounting for 62% (n =215,850) of the enrolled participants and female participants for just 38% (n =133,082). Male participants formed most of trial cohorts in AKI (65%), CKD (62%), dialysis (55%), and transplant trials (65%), whereas women were majority enrollees in GN trials (61%). CKD trials under-represented women in both US trials and worldwide.

Conclusions

Women are under-represented in high-impact nephrology trials with the exception of GN trials. This imbalance may contribute to disparities in outcomes and gaps in the care of women with kidney disease.

Tenapanor Improves Long-Term Control of Hyperphosphatemia in Patients Receiving Maintenance Dialysis: the NORMALIZE Study

Key Points

Tenapanor is a first-in-class, minimally systemic sodium–hydrogen exchanger 3 inhibitor with a mechanism of action distinct from phosphate binders. Tenapanor alone or with phosphate binders led to 35%–49% of patients achieving serum phosphate ≤4.5 mg/dl over an 18-month period versus 22% at baseline. Tenapanor alone or with phosphate binders may help adults with CKD on maintenance dialysis achieve normal serum phosphate concentrations.

Background

Most patients with ESKD and hyperphosphatemia have difficulty controlling serum phosphate (sP) concentrations despite maintenance dialysis, dietary restriction, and phosphate binder treatment. NORMALIZE evaluated the efficacy and safety of tenapanor 30 mg twice daily alone or in combination with phosphate binders to achieve sP within the adult population reference range (2.5–4.5 mg/dl).

Methods

Patients who completed the Phase 3 PHREEDOM study could enroll in NORMALIZE. Patients enrolled in NORMALIZE who had received tenapanor during the PHREEDOM study (n =111) added sevelamer carbonate if sP was >4.5 mg/dl. Patients who had received sevelamer carbonate during the PHREEDOM study (n =61) added tenapanor and decreased sevelamer carbonate if sP was ≤4.5 mg/dl, per protocol titration schedule. Patients were followed in NORMALIZE for up to 18 months. We assessed efficacy in the full analysis set, defined as patients who received ≥1 dose of study drug and had ≥1 post-treatment sP measurement (n =171). We assessed safety in all patients who received ≥1 dose of study drug (n =172).

Results

At the end point visit, 57 of 171 patients (33%) in the full analysis set achieved sP between 2.5 and 4.5 mg/dl. Eight of 23 patients (35%) who were on tenapanor alone at the end point visit achieved sP between 2.5 and 4.5 mg/dl. The mean reduction from PHREEDOM baseline to end of NORMALIZE in sP was 2.0 mg/dl. Serum intact fibroblast growth factor-23 was significantly reduced; serum intact parathyroid hormone was significantly reduced among patients with intact parathyroid hormone ≥300 pg/ml at PHREEDOM baseline. The most commonly reported treatment-emergent adverse event was diarrhea in 38 of 172 patients (22%), which led to tenapanor discontinuation in four patients (2%).

Conclusions

Tenapanor alone or in combination with phosphate binders helped adult patients on maintenance dialysis achieve normal sP concentrations. Safety was consistent with previous studies of tenapanor.

Clinical trial registry name and registration number

A Long-Term Study to Evaluate the Ability of Tenapanor Alone or in Combination With Sevelamer to Treat to Goal Serum Phosphorus in Patients With ESKD on Dialysis (NORMALIZE), NCT03988920 .

Genetic Inhibition of APOL1 Pore-Forming Function Prevents APOL1-Mediated Kidney Disease

SIGNIFICANCE STATEMENT

African Americans are at increased risk of CKD in part due to high-risk (HR) variants in the apolipoprotein L1 ( APOL1 ) gene, termed G1/G2. A different APOL1 variant, p.N264K , reduced the risk of CKD and ESKD among carriers of APOL1 HR variants to levels comparable with individuals with APOL1 low-risk variants in an analysis of 121,492 participants of African ancestry from the Million Veteran Program (MVP). Functional genetic studies in cell models showed that APOL1 p.N264K blocked APOL1 pore-forming function and ion channel conduction and reduced toxicity of APOL1 HR mutations. Pharmacologic inhibitors that mimic this mutation blocking APOL1 -mediated pore formation may be able to prevent and/or treat APOL1 -associated kidney disease.

BACKGROUND

African Americans are at increased risk for nondiabetic CKD in part due to HR variants in the APOL1 gene.

METHODS

We tested whether a different APOL1 variant, p.N264K , modified the association between APOL1 HR genotypes (two copies of G1/G2) and CKD in a cross-sectional analysis of 121,492 participants of African ancestry from the MVP. We replicated our findings in the Vanderbilt University Biobank ( n =14,386) and National Institutes of Health All of Us ( n =14,704). Primary outcome was CKD and secondary outcome was ESKD among nondiabetic patients. Primary analysis compared APOL1 HR genotypes with and without p.N264K . Secondary analyses included APOL1 low-risk genotypes and tested for interaction. In MVP, we performed sequential logistic regression models adjusting for demographics, comorbidities, medications, and ten principal components of ancestry. Functional genomic studies expressed APOL1 HR variants with and without APOL1 p.N264K in cell models.

RESULTS

In the MVP cohort, 15,604 (12.8%) had two APOL1 HR variants, of which 582 (0.5%) also had APOL1 p.N264K . In MVP, 18,831 (15%) had CKD, 4177 (3%) had ESKD, and 34% had diabetes. MVP APOL1 HR, without p.N264K , was associated with increased odds of CKD (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.60 to 1.85) and ESKD (OR, 3.94; 95% CI, 3.52 to 4.41). In MVP, APOL1 p.N264K mitigated the renal risk of APOL1 HR, in CKD (OR, 0.43; 95% CI, 0.28 to 0.65) and ESKD (OR, 0.19; CI 0.07 to 0.51). In the replication cohorts meta-analysis, APOL1 p.N264K mitigated the renal risk of APOL1 HR in CKD (OR, 0.40; 95% CI, 0.18 to 0.92) and ESKD (OR, 0.19; 95% CI, 0.05 to 0.79). In the mechanistic studies, APOL1 p.N264K blocked APOL1 pore-forming function and ion channel conduction and reduced toxicity of APOL1 HR variants.

CONCLUSIONS

APOL1 p.N264K is associated with reduced risk of CKD and ESKD among carriers of APOL1 HR to levels comparable with individuals with APOL1 low-risk genotypes.

The Crosstalk between Nephropathy and Coagulation Disorder: Pathogenesis, Treatment, and Dilemmas

ABSTRACT

The interaction between the kidney and the coagulation system greatly affects each other because of the abundant vessel distribution and blood perfusion in the kidney. Clinically, the risks of complicated thrombosis and bleeding have become important concerns in the treatment of nephropathies, especially nephrotic syndrome, CKD, ESKD, and patients with nephropathy undergoing RRTs. Adverse effects of anticoagulant or procoagulant therapies in patients with nephropathy, especially anticoagulation-related nephropathy, heparin-induced thrombocytopenia, and bleeding, seriously worsen the prognosis of patients, which have become challenges for clinicians. Over the decades, the interaction between the kidney and the coagulation system has been widely studied. However, the effects of the kidney on the coagulation system have not been systematically investigated. Although some coagulation-related proteins and signaling pathways have been shown to improve coagulation abnormalities while avoiding additional kidney damage in certain kidney diseases, their potential as anticoagulation targets in nephropathy requires further investigation. Here, we review the progression of research on the crosstalk between the coagulation system and kidney diseases and systematically analyze the significance and shortcomings of previous studies to provide new sight into future research. In addition, we highlight the status of clinical treatment for coagulation disorder and nephropathy caused by each other, indicating guidance for the formulation of therapeutic strategies or drug development.

Outcomes of Hospital-Acquired Hypernatremia

BACKGROUND

Hospital-acquired hypernatremia is highly prevalent, overlooked, and associated with unfavorable consequences. There are limited studies examining the outcomes and discharge dispositions of various levels of hospital-acquired hypernatremia in patients with or without CKD.

METHODS

We conducted an observational retrospective cohort study, and we analyzed the data of 1,728,141 patients extracted from the Cerner Health Facts database (January 1, 2000, to June 30, 2018). In this report, we investigated the association between hospital-acquired hypernatremia (serum sodium [Na] levels >145 mEq/L) and in-hospital mortality or discharge dispositions with kidney function status at admission using adjusted multinomial regression models.

RESULTS

Of all hospitalized patients, 6% developed hypernatremia after hospital admission. The incidence of in-hospital mortality was 12% and 1% in patients with hypernatremia and normonatremia, respectively. The risk of all outcomes was significantly greater for serum Na >145 mEq/L compared with the reference interval (serum Na, 135-145 mEq/L). In patients with hypernatremia, odds ratios (95% confidence interval) for in-hospital mortality, discharge to hospice, and discharge to nursing facilities were 14.04 (13.71 to 14.38), 4.35 (4.14 to 4.57), and 3.88 (3.82 to 3.94), respectively ( P < 0.001, for all). Patients with eGFR (Chronic Kidney Disease Epidemiology Collaboration) 60-89 ml/min per 1.73 m 2 and normonatremia had the lowest odds ratio for in-hospital mortality (1.60 [1.52 to 1.70]).

CONCLUSIONS

Hospital-acquired hypernatremia is associated with in-hospital mortality and discharge to hospice or to nursing facilities in all stages of CKD.

Taurolidine/Heparin Lock Solution and Catheter-Related Bloodstream Infection in Hemodialysis: A Randomized, Double-Blind, Active-Control, Phase 3 Study

BACKGROUND

Catheter-related bloodstream infections (CRBSIs) are one of the most prevalent, fatal, and costly complications of hemodialysis with a central venous catheter (CVC). The LOCK IT-100 trial compared the efficacy and safety of a taurolidine/heparin catheter lock solution that combines taurolidine 13.5 mg/ml and heparin (1000 units/ml) versus heparin in preventing CRBSIs in participants receiving hemodialysis via CVC.

METHODS

LOCK IT-100 was a randomized, double-blind, active-control, multicenter, phase 3 study that enrolled adults with kidney failure undergoing maintenance hemodialysis via CVC from 70 US sites. Participants were randomized 1:1 to taurolidine/heparin catheter lock solution or heparin control catheter lock solution (1000 units/ml). The primary end point was time to CRBSI as assessed by a blinded Clinical Adjudication Committee. Secondary end points were catheter removal for any reason and loss of catheter patency. On the basis of a prespecified interim analysis, the Data and Safety Monitoring Board recommended terminating the trial early for efficacy with no safety concerns.

RESULTS

In the full analysis population ( N =795), nine participants in the taurolidine/heparin arm ( n =397; 2%) and 32 participants in the heparin arm ( n =398; 8%) had a CRBSI. Event rates per 1000 catheter days were 0.13 and 0.46, respectively, with the difference in time to CRBSI being statistically significant, favoring taurolidine/heparin ( P < 0.001). The hazard ratio was 0.29 (95% confidence interval, 0.14 to 0.62), corresponding to a 71% reduction in risk of CRBSIs with taurolidine/heparin versus heparin. There were no significant differences between study arms in time to catheter removal for any reason or loss of catheter patency. The safety of taurolidine/heparin was comparable with that of heparin, and most treatment-emergent adverse events were mild or moderate.

CONCLUSIONS

Taurolidine/heparin reduced the risk of developing a CRBSI in study participants receiving hemodialysis via CVC compared with heparin with a comparable safety profile.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Study Assessing Safety & Effectiveness of a Catheter Lock Solution in Dialysis Patients to Prevent Bloodstream Infection, NCT02651428 .

Molecular Phenotyping and Mechanisms of Myocardial Fibrosis in Advanced Chronic Kidney Disease

Key Points

Myocardial fibrosis in hearts from patients with CKD is characterized by increased trimeric tensile collagen type I and decreased elastic collagen type III compared with hearts from hypertensive or healthy donors, suggesting a unique fibrotic phenotype. Myocardial fibrosis in CKD is driven by alterations in extracellular matrix proteostasis, including dysregulation of metalloproteinases and cross-linking enzymes. CKD-associated mineral stressors uniquely induce a fibronectin-independent mechanism of fibrillogenesis characterized by formation of trimeric collagen compared with proinflammatory/fibrotic cytokines.

Background

Myocardial fibrosis is a major life-limiting problem in CKD. Despite this, the molecular phenotype and metabolism of collagen fibrillogenesis in fibrotic hearts of patients with advanced CKD have been largely unstudied.

Methods

We analyzed explanted human left ventricular (LV) heart tissues in a three-arm cross-sectional cohort study of deceased donor patients on hemodialysis (HD, n =18), hypertension with preserved renal function (HTN, n =8), and healthy controls (CON, n =17), ex vivo . RNA-seq and protein analysis was performed on human donor hearts and cardiac fibroblasts treated with mineral stressors (high phosphate and high calcium). Further mechanistic studies were performed using primary cardiac fibroblasts, in vitro treated with mineral stressors, proinflammatory and profibrotic cytokines.

Results

Of the 43 donor participants, there was no difference in age (P > 0.2), sex (P > 0.8), or body mass index (P > 0.1) between the groups. Hearts from the HD group had extensive fibrosis (P < 0.01). All LV tissues expressed only the trimeric form of collagen type I. HD hearts expressed increased collagen type I (P < 0.03), elevated collagen type I:III ratio (P < 0.05), and decreased MMP1 (P < 0.05) and MMP2 (P < 0.05). RNA-seq revealed no significant differential gene expression of extracellular matrix proteins of interest in HD hearts, but there was significant upregulation of LH2, periostin, α -SMA, and TGF-β 1 gene expression in mineral stressor–treated cardiac fibroblasts. Both mineral stressors (P < 0.009) and cytokines (P < 0.03) increased collagen type I:III ratio. Mineral stressors induced trimeric collagen type I, but cytokine treatment induced only dimeric collagen type I in cardiac fibroblasts. Mineral stressors downregulated fibronectin (P < 0.03) and MMP2 zymogen (P < 0.01) but did not significantly affect expression of periostin, MMP1, or cross-linking enzymes. TGF-β upregulated fibronectin (P < 0.01) and periostin (P < 0.02) only.

Conclusions

Myocardial fibrosis in advanced CKD hearts is characterized by increased trimeric collagen type I and dysregulated collagen metabolism, and is differentially regulated by components of uremia.

Patient Preference Trade-offs for Next-Generation Kidney Replacement Therapies

BACKGROUND

Next-generation implantable and wearable KRTs may revolutionize the lives of patients undergoing dialysis by providing more frequent and/or prolonged therapy along with greater mobility compared with in-center hemodialysis. Medical device innovators would benefit from patient input to inform product design and development. Our objective was to determine key risk/benefit considerations for patients with kidney failure and test how these trade-offs could drive patient treatment choices.

METHODS

We developed a choice-based conjoint discrete choice instrument and surveyed 498 patients with kidney failure. The choice-based conjoint instrument consisted of nine attributes of risk and benefit pertinent across KRT modalities. Attributes were derived from literature reviews, patient/clinician interviews, and pilot testing. The risk attributes were serious infection, death within 5 years, permanent device failure, surgical requirements, and follow-up requirements. The benefit attributes were fewer diet restrictions, improved mobility, pill burden, and fatigue. We created a random, full-profile, balanced overlap design with 14 choice pairs plus five fixed tasks to test validity. We used a mixed-effects regression model with attribute levels as independent predictor variables and choice decisions as dependent variables.

RESULTS

All variables were significantly important to patient choice preferences, except follow-up requirements. For each 1% higher risk of death within 5 years, preference utility was lower by 2.22 ( β =-2.22; 95% confidence interval [CI], -2.52 to -1.91), while for each 1% higher risk of serious infection, utility was lower by 1.38 ( β =-1.46; 95% CI, -1.77 to -1.00) according to comparisons of the β coefficients. Patients were willing to trade a 1% infection risk and 0.5% risk of death to gain complete mobility and freedom from in-center hemodialysis ( β =1.46; 95% CI, 1.27 to 1.64).

CONCLUSIONS

Despite an aversion to even a 1% higher risk of death within 5 years, serious infection, and permanent device rejection, patients with kidney failure suggested that they would trade these risks for the benefit of complete mobility.

The Complex Patchwork of Transportation for In-Center Hemodialysis

Reliable transportation is an important determinant of access to health care and health outcomes that carries particular significance for people with ESKD. In the United States, there are almost half a million patients receiving treatment with in-center dialysis, translating into more than 70 million roundtrips to dialysis centers annually. Difficulty with transportation can interfere with patients' quality of life and contribute to missed or shortened dialysis treatments, increasing their risk for hospitalization. Medicare, the principal payer for dialysis in this country, has not traditionally provided coverage for nonemergency medical transportation, placing the burden of traveling to and from the dialysis center on patients and families and a range of other private and public entities that were not designed and are poorly equipped for this purpose. Here, we review the relationship between access to reliable transportation and health outcomes such as missed and shortened dialysis treatments, hospitalizations, and quality of life. We also describe current approaches to the delivery of transportation for patients receiving in-center hemodialysis, highlighting potential opportunities for improvement.

Performance Characteristics of Candidate Criteria for Hemodialysis Arteriovenous Fistula Maturation

BACKGROUND

Twenty to 60% of newly created hemodialysis arteriovenous fistulas do not mature adequately for use. One barrier to developing interventions to improve fistula outcomes is a lack of standardized criteria for maturation.

METHODS

Using data from the multicenter, prospective Hemodialysis Fistula Maturation (HFM) Study, we determined sensitivities, specificities, and positive and negative predictive values of multiple candidate maturation criteria using the HFM Study maturation criteria as the reference. We also compared, across the maturation criteria, relationships between maturation and fistula survival using Cox proportional hazards models.

RESULTS

We included 535 of the 602 HFM Study participants. The median (interquartile range) age was 57 (47-65) years, 70% were men, and 45% were Black participants. Depending on the criterion and time frame for ascertainment (3, 4, 5, 6, or 9 months), sensitivities ranged from 57% to 100%, specificities ranged from 85% to 100%, positive predictive values ranged from 88% to 100%, and negative predictive values ranged from 65% to 100%. For all criteria, areas under the curve for the 6-month (0.90-0.97 for unassisted maturation and 0.89-0.95 for overall maturation) and 9-month time frames were similar. Attainment of unassisted maturation was associated with lower risks of fistula abandonment, with hazard ratios ranging from 0.10 to 0.40 depending on the criterion and time frame. Eliminating dialysis adequacy indicators, or simplifying the criteria in other ways, had little effect on performance characteristics.

CONCLUSIONS

High performance characteristics are maintained with maturation criteria that are simpler and less burdensome to ascertain than the HFM Study outcome measure.

Automated Digital Counseling Program (ODYSSEE-Kidney Health): A Pilot Study on Health-Related Quality of Life

Key Points

Feasibility of implementing an automated, scalable, digital self-care program for patients with CKD was established. The primary outcome of improvement in health-related quality of life improved with the ODYSSEE-Kidney Health program. A dose relationship was shown between program engagement tertile and improvement in 4-month outcomes.

Background

In-person counseling programs promote self-care behavior and health-related quality of life (HRQoL). ODYSSEE-Kidney Health (prO moting health with D igitallY based counS eling for S elf-care bE havior and quality of lifE ; ODYSSEE-KH) is an automated, scalable, digital counseling program for patients with CKD. This open-label, single-arm pilot study tested the efficacy potential of the ODYSSEE-KH program to improve HRQoL in patients with CKD.

Methods

Adults with categories G3b to 5d CKD were recruited from nephrology clinics in Toronto, Canada. Patients (N =29) received access to the ODYSSEE-KH program in conjunction with usual care. Generalized linear models and pairwise comparisons of mean change scores were conducted to assess the primary outcome: Mental Component Score (MCS) of the Kidney Disease Quality of Life–Short Form instrument. Secondary outcomes included the MCS Mental Health Scale, 36-Item Kidney Disease Quality of Life–Short Form, Generalized Anxiety Disorder Scale, Patient Health Questionnaire for depression, Enhancing Recovery in Coronary Heart Disease Social Support Instrument, and 3-Item Revised University of California, Los Angeles (UCLA) Loneliness Scale.

Results

The mean age of the patients was 53.5 years (SD=18.3); 35% were women; 56% were White; 93% had completed ≥postsecondary education; patients came from the Multi-Care Kidney Clinic (n =9), Home Peritoneal Dialysis Unit (n =12), and Home Hemodialysis Unit (n =8); and 24 participants completed the 4-month end-of-study questionnaires. Outcomes were assessed according to tertiles of program log-on minutes: median (range)=67 (62–108), 212 (119–355), and 500 (359–1573) minutes, respectively. Patients in the highest tertile of engagement showed significant improvements on the MCS versus the moderate tertile group (P = 0.01). Significant dose-response associations were observed for the MCS Mental Health Scale (P < 0.05), KDQoL Burden on Kidney Disease (P < 0.01), KDQoL Effect of Kidney Disease on Everyday Life (P < 0.01), aggregated KDQoL Summary Scale (P < 0.05), Generalized Anxiety Disorder Scale (P < 0.01), Patient Health Questionnaire for Depression (P < 0.05), Enhancing Recovery in Coronary Heart Disease Social Support Instrument (P < 0.01), and 3-Item Revised UCLA Loneliness Scale (P < 0.01).

Conclusion

The ODYSSEE-KH program demonstrated feasibility as an automated, scalable, digital self-care program for patients with CKD. There is evidence of its efficacy potential to improve HRQoL. Further evaluation with a larger sample is warranted.

Impact of Diabetic Lesions on Pathology, Treatment, and Outcomes of Glomerular Diseases

Key Points

People with glomerular disease (GD) and comorbid diabetes have similar baseline characteristics irrespective of superimposed diabetic lesions. Immunosuppression for GD with comorbid diabetes is the same regardless of superimposed diabetic glomerular lesions. ESKD or death is more rapid in GD and comorbid diabetes only in the presence of moderate-severe diabetic glomerular lesions.

Background

We aimed to evaluate whether concomitant diabetic glomerulosclerosis (DGS) and its severity affect the treatment and outcomes of primary glomerular diseases (GDs) with comorbid diabetes.

Methods

We conducted a retrospective review of people with diabetes and GD. We searched the GD Collaborative Network for biopsies from 2008 to 2015 among persons with diabetes and any of the following diagnoses: FSGS, IgA nephropathy, minimal change disease, membranous nephropathy, or antineutrophil cytoplasmic autoantibody GN. Data were abstracted from health records and histologic diabetic glomerular class scored. The primary composite end point was ESKD or death. Multivariable Cox regression models tested whether any or the severity of diabetes histopathology affected the primary end point.

Results

Data from 134 cases were available for analysis (78 DGS+GD and 56 GD alone). Diabetes duration and glycemic control were similar between the two groups (P = 0.2; P = 0.09, respectively). Use of immunosuppression did not differ between the two groups (P = 0.3). The composite end point was significantly higher in DGS+GD (22.5 cases per 100 person-years [95% confidence interval (CI), 16.6 to 30.5]) versus GD alone (10.2 cases per 100 person-years [95% CI, 6.4 to 16.2]). Regression analyses demonstrated that compared with the GD-alone group, the risk for the composite end point was similar in the group with mild DGS+GD (DGS class 1, 2a) (hazard ratio, 1.15 [95% CI, 0.54 to 2.43]) while the group with severe DGS+GD (DGS class 2b, 3, 4) had a greater risk (hazard ratio, 3.60 [1.79 to 7.22]).

Conclusions

Among people with diabetes and GD, mild diabetic glomerular lesions on biopsy do not affect outcomes, but moderate-severe lesions increase the risk for ESKD and death. Whether use of immunosuppression, particularly glucocorticoids, is less successful in inducing GD remission in people with moderate-severe diabetic lesions will be a focus of future study in a larger population.

Dysfunctional Coupling of Cerebral Blood Flow and Susceptibility Value in the Bilateral Hippocampus is Associated with Cognitive Decline in Nondialysis Patients with CKD

SIGNIFICANCE STATEMENT

Patients with end stage CKD often develop cognitive decline, but whether this is related to the underlying disease or to hemodialysis remains unclear. We performed three-dimensional pseudocontinuous arterial spin labeling and quantitative susceptibility mapping prospectively in 40 patients with stage 1-4 CKD, 47 nondialysis patients with stage 5 CKD, and 44 healthy controls. Our magnetic resonance imaging data demonstrate that changes in cerebral blood flow-susceptibility coupling might underlie this cognitive decline, perhaps in the hippocampus and thalamus. These results suggest that magnetic resonance imaging parameters are potential biomarkers of cognitive decline in patients with CKD. Moreover, our findings may lead to discovery of novel therapeutic targets to prevent cognitive decline in patients with CKD.

BACKGROUND

Cerebral blood flow (CBF) and susceptibility values reflect vascular and iron metabolism, providing mechanistic insights into conditions of health and disease. Nondialysis patients with CKD show a cognitive decline, but the pathophysiological mechanisms underlying this remain unclear.

METHODS

Three-dimensional pseudocontinuous arterial spin labeling and quantitative susceptibility mapping were prospectively performed in 40 patients with stage 1-4 CKD (CKD 1-4), 47 nondialysis patients with stage 5 CKD (CKD 5ND), and 44 healthy controls (HCs). Voxel-based global and regional analyses of CBF, susceptibility values, and vascular-susceptibility coupling were performed. Furthermore, the association between clinical performance and cerebral perfusion and iron deposition was analyzed.

RESULTS

For CBF, patients with CKD 5ND had higher normalized CBF in the hippocampus and thalamus than HCs. Patients with CKD 5ND had higher normalized CBF in the hippocampus and thalamus than those with CKD 1-4. The susceptibility values in the hippocampus and thalamus were lower in patients with CKD 5ND than in HCs. Patients with CKD 5ND had higher susceptibility value in the caudate nucleus than those with CKD 1-4. More importantly, patients with CKD 5ND had lower CBF-susceptibility coupling than HCs. In addition, CBF and susceptibility values were significantly associated with clinical performance.

CONCLUSIONS

Our findings demonstrate a new neuropathological mechanism in patients with CKD, which leads to regional changes in CBF-susceptibility coupling. These changes are related to cognitive decline, providing potential imaging markers for assessing clinical disability and cognitive decline in these patients.

Needs and Considerations for Standardization of Kidney Disease Education in Patients with Advanced CKD

Kidney health advocacy organizations and leaders in the nephrology community have repeatedly emphasized the need to increase home dialysis utilization in the United States. Limited awareness and understanding of options for the management of kidney failure among patients living with advanced CKD is a significant barrier to increasing the selection and use of home dialysis. Studies have shown that providing targeted comprehensive patient education before the onset of kidney failure can improve patients' awareness of kidney disease and substantially increase the informed utilization of home dialysis. Unfortunately, in the absence of validated evidence-based education protocols, outcomes associated with home dialysis use vary widely among published studies, potentially affecting the routine implementation and reporting of these services among patients with advanced CKD. This review provides pragmatic guidance on establishing effective patient-centered education programs to empower patients to make informed decisions about their KRT and, in turn, increase home dialysis use.

Management of Patients with Gout and Kidney Disease: A Review of Available Therapies and Common Missteps

Gout, a common form of inflammatory arthritis, is characterized by deposition of monosodium urate crystals in articular and periarticular tissues. Repeated flares of gout cause joint damage as well as significant health care utilization and decreased quality of life. Patients with CKD have a higher prevalence of gout. Treating Patients with CKD and gout is challenging because of the lack of quality data to guide management in this specific population. This often leads to suboptimal treatment of patients with gout and impaired renal function because concerns regarding the efficacy and safety of available gout therapies in this population often result in significant interphysician variability in treatment regimens and dosages. Acute gout flares are treated with various agents, including nonsteroidal anti-inflammatory drugs, colchicine, glucocorticoids, and-more recently-IL-1 inhibitors. These medications can also be used as prophylaxis if urate-lowering therapy (ULT) is initiated. While these drugs can be used in patients with gout and CKD, there are often factors that complicate treatment, such as the numerous medication interactions involving colchicine and the effect of glucocorticoids on common comorbidities, such as diabetes and hypertension. ULT is recommended to treat recurrent flares, tophaceous deposits, and patients with moderate-to-severe CKD with a serum urate goal of <6 mg/dl recommended to prevent flares. While many misconceptions exist around the risks of using urate-lowering agents in patients with CKD, there is some evidence that these medications can be used safely in Patients with renal impairment. Additional questions exist as to whether gout treatment is indicated for Patients on RRT. Furthermore, there are conflicting data on whether ULT can affect renal function and cardiovascular disease in patients. All of these factors contribute to the unique challenges physicians face when treating patients with gout and CKD.

Immunosuppression versus Supportive Care on Kidney Outcomes in IgA Nephropathy in the Real-World Setting

BACKGROUND

The efficacy of immunosuppression in the management of immunoglobulin A (IgA) nephropathy remains highly controversial. The study was conducted to assess the effect of immunosuppression, compared with supportive care, in the real-world setting of IgA nephropathy.

METHODS

A cohort of 3946 patients with IgA nephropathy, including 1973 new users of immunosuppressive agents and 1973 propensity score-matched recipients of supportive care, in a nationwide register data from January 2019 to May 2022 in China was analyzed. The primary outcome was a composite of 40% eGFR decrease of the baseline, kidney failure, and all-cause mortality. A Cox proportional hazard model was used to estimate the effects of immunosuppression on the composite outcomes and its components in the propensity score-matched cohort.

RESULTS

Among 3946 individuals (mean [SD] age 36 [10] years, mean [SD] eGFR 85 [28] ml/min per 1.73 m 2 , and mean [SD] proteinuria 1.4 [1.7] g/24 hours), 396 primary composite outcome events were observed, of which 156 (8%) were in the immunosuppression group and 240 (12%) in the supportive care group. Compared with supportive care, immunosuppression treatment was associated with 40% lower risk of the primary outcome events (adjusted hazard ratio, 0.60; 95% confidence interval, 0.48 to 0.75). Comparable effect size was observed for glucocorticoid monotherapy and mycophenolate mofetil alone. In the prespecified subgroup analysis, the treatment effects of immunosuppression were consistent across ages, sexes, levels of proteinuria, and values of eGFR at baseline. Serious adverse events were more frequent in the immunosuppression group compared with the supportive care group.

CONCLUSIONS

Immunosuppressive therapy, compared with supportive care, was associated with a 40% lower risk of clinically important kidney outcomes in patients with IgA nephropathy.

Structural Racism, Historical Redlining, and Incidence of Kidney Failure in US Cities, 2012-2019

SIGNIFICANCE STATEMENT

Residing in neighborhoods designated as grade D (hazardous) by the Home Owners' Loan Corporation (HOLC) under historical redlining-a discriminatory housing policy beginning in the 1930s-has been associated with present-day adverse health outcomes such as diabetes mortality. Historical redlining might underlie conditions in present-day neighborhoods that contribute to inequitable rates of kidney failure incidence, particularly for Black individuals, but its association with kidney disease is unknown. The authors found that among adults with incident kidney failure living in 141 metropolitan areas, residence in a historically redlined neighborhood rated grade D was associated with significantly higher kidney failure incidence rates compared with residence in a redlined grade A (best) neighborhood. These findings suggest that historical racist policies continue to affect current-day racial inequities in kidney health.

BACKGROUND

Historical redlining was a 1930s federally sponsored housing policy that permitted the Home Owners' Loan Corporation (HOLC) to develop color-coded maps and grade neighborhoods' mortgage lending risk on the basis of characteristics that included racial makeup. This practice has been associated with present-day health disparities. Racial inequities in kidney disease-particularly for Black individuals-have been linked to residential segregation and other structural inequities.

METHODS

Using a registry of people with incident kidney failure and digitized HOLC maps, we examined the association between residence in a historically redlined US census tract (CT) with a historical HOLC grade of D or hazardous) and present-day annual CT-level incidence of kidney failure incidence among adults in 141 US metropolitan areas, in 2012 through 2019.

RESULTS

Age-adjusted and sex-adjusted kidney failure incidence rates were significantly higher in CTs with a historical HOLC grade D compared with CTs with a historical HOLC grade of A or best (mean, 740.7 per million versus 326.5 per million, respectively, a difference of 414.1 per million). Compared with national averages of all adults in our sample, rates of kidney failure incidence were higher for Black adults in our study sample, irrespective of CT HOLC grade. Age-adjusted and sex-adjusted incidence rates for Black persons in CTs with a HOLC grade D were significantly higher than for Black persons residing in HOLC grade A CTs (mean, 1227.1 per million versus 1030.5 per million, respectively [a difference of 196.6 per million]).

CONCLUSIONS

Historical redlining is associated with present-day disparities in kidney failure incidence, demonstrating the legacy of historical racist policies on contemporary racial inequities in kidney health.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2023_08_24_JASN0000000000000165.mp3.

Risk of Death among Dialysis Patients Treated at Hospital-Affiliated versus Free-Standing Facilities in the United States

Receipt of dialysis at hospital-affiliated facilities was associated with a higher risk of mortality compared with treatment at free-standing dialysis facilities. The differential mortality risk in free-standing versus hospital-affiliated facilities was more pronounced in non-Hispanic Black and Asian patients compared with other racial/ethnic groups.

Timing of Kidney Replacement Therapy among Children and Young Adults

BACKGROUND

No randomized trials exist to guide the timing of the initiation of KRT in children. We sought to define trends and predictors of the eGFR at initiation of KRT, center-related clinical practice variation, and any association with patient survival.

METHODS

Children and young adults (1-25 years) commencing KRT (dialysis or kidney transplantation) between 1995 and 2018 were included using data from the Australia and New Zealand Dialysis and Transplant Registry. The associations between eGFR on commencing KRT and covariates were estimated using quantile regression. Cox regression was used to estimate the association between eGFR and patient survival. Logistic regression, categorizing eGFR about a value of 10 ml/min per 1.73 m 2 , was used in conjunction with a random effect by center to quantify clinical practice variation.

RESULTS

Overall, 2274 participants were included. The median eGFR at KRT initiation increased from 7 to 9 ml/min per 1.73 m 2 over the study period and the 90th centile from 11 to 17 ml/min per 1.73 m 2 . The effect of era on median eGFR was modified by modality, with a greater increase among those receiving a preemptive kidney transplant (1.0 ml/min per 1.73 m 2 per 5 years; 95% confidence interval [CI], 0.6 to 1.5) or peritoneal dialysis (0.7 ml/min per 1.73 m 2 per 5 years; 95% CI, 0.4 to 0.9) compared with hemodialysis (0.1 ml/min per 1.73 m 2 per 5 years; 95% CI, -0.1 to 0.3). There were 252 deaths (median follow-up 8.5 years, interquartile range 3.7-14.2) and no association between eGFR and survival (hazard ratio, 1.01 per ml/min per 1.73 m 2 ; 95% CI, 0.98 to 1.04). Center variation explained 6% of the total variance in the odds of initiating KRT earlier. This rose to over 10% when comparing pediatric centers alone.

CONCLUSIONS

Children and young adults progressively commenced KRT earlier. This change was more pronounced for children starting peritoneal dialysis or receiving a preemptive kidney transplant. Earlier initiation of KRT was not associated with any difference in patient survival. A substantial proportion of clinical practice variation was due to center variation alone.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_08_08_CJN0000000000000204.mp3.

Overcoming Barriers to Drug Development in Children with CKD

Like all sick children, children with CKD need access to safe and effective medicines that have been formulated and examined specifically for them. Despite legislation in the United States and the European Union that either mandates or incentivizes programs for children, conducting trials to advance the treatment of children continues to prove to be a challenge for drug developers. This is also the case for drug development in children with CKD, where trials face challenges in recruitment and completion and where there remains a substantial time lag between initial approval of a medicinal product for use in adults and completion of studies that result in the addition of pediatric-specific labeling for the same indication. The Kidney Health Initiative commissioned a workgroup of diverse stakeholders ( https://khi.asn-online.org/projects/project.aspx?ID=61 ), including participants from the Food and Drug Administration and the European Medicines Agency, to think carefully through the challenges in drug development for children with CKD and how to overcome them. This article provides an overview of the regulatory frameworks in the United States and the European Union that govern pediatric drug development, the current landscape of drug development and approval for children with CKD, the challenges in conduct and execution of these drug trials, and the progress that has been made to facilitate drug development for children with CKD.