Comparing Medicare Fee-for-Service Beneficiaries with ESKD who Switched to Medicare Advantage versus Remained in Traditional Medicare.

ABSTRACT: Patients choosing Medicare Advantage vs. Medicare fee-for-service (FFS) differ with respect to race, socioeconomic status, and burden of disease. However, it is unclear whether these differences also occur among patients with kidney failure, who were newly allowed to switch to Medicare Advantage after the 21st Century Cares Act. We used data from the United States Renal Data System (USRDS) to examine differences in characteristics of dialysis patients and kidney transplant recipients who switched from FFS to Medicare Advantage compared with those who stayed with FFS in 2021, the first year such switching was allowed. We used unadjusted and adjusted logistic regression to compare odds of switching among demographic and geographic subgroups. Among 411,513 patients with FFS coverage in 2020, 10.1% switched to Medicare Advantage in 2021. Switchers constituted 12% of the dialysis population and 5% of the kidney transplant population. In the dialysis population, patients of Black race and Hispanic ethnicity were more likely to switch than patients of White race (adjusted OR 1.69, 95% Confidence Interval [CI] 1.64, 1.73 and OR 1.42, 95% CI 1.40, 1.47, respectively), as were patients with dual eligibility for Medicaid (adjusted OR 1.12, 95% CI 1.09, 1.15). Patients living in the South were also more likely to switch to Medicare Advantage than those living in the West (adjusted OR 1.48, 95% CI 1.43, 1.52). Similar differences were observed among kidney transplant recipients. Patients who switched from FFS to Medicare Advantage were disproportionately from historically marginalized groups, including Black, Hispanic, and low income individuals. They were also more likely to live in the South. These differences may threaten the generalizability of USRDS data that relies on FFS insurance claims and suggest that comparisons of outcomes between FFS and MA beneficiaries with kidney failure should be adjusted for key patient characteristics.

A cohort study of sodium-glucose cotransporter-2 inhibitors after acute kidney injury among Veterans with diabetic kidney disease.

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) reduce the risk for several adverse outcomes among patients with diabetic kidney disease. Yet, optimal timing for SGLT2i after acute kidney injury (AKI) is uncertain, as are the providers responsible for post-AKI SGLT2i initiation. Using a retrospective cohort of United States Veterans with diabetes mellitus type 2 and proteinuria, we examined encounters by provider specialty before SGLT2i initiation and subsequent all-cause mortality after hospitalization with AKI, defined by a 50% or more rise in serum creatinine. Covariates included recovery, defined by return to a 110% or less of baseline creatinine, and time since AKI hospitalization. Among 21,330 eligible Veterans, 7,798 died (37%) and 6,562 received a SGLT2i (31%) over median follow-up of 2.1 years. Post-AKI SGLT2i use was associated with lower mortality risk [adjusted hazard ratio 0.63 (95% confidence interval 0.58-0.68)]. Compared with neither SGLT2i use nor recovery, mortality risk was similar with recovery without SGLT2i use [0.97 (0.91-1.02)] but was lower without recovery prior to SGLT2i use [0.62 (0.55-0.71)] and with SGLT2i use after recovery [0.60 (0.54-0.67)]. Finally, the effect of SGLT2i was stable over time (P for time-interaction 0.19). Thus, we observed reduced mortality with SGLT2i use after AKI among Veterans with diabetic kidney disease whether started earlier or later or before or after observed recovery. Hence, patients with diabetic kidney disease who receive a SGLT2i earlier after AKI experience no significant harm impacting mortality and experience a lower mortality risk than those who do not.

Plant-based diets in patients with chronic kidney disease.

Dietary protein restriction has been considered to be a nutritional-related strategy to reduce risk for end-stage kidney disease among patients with non-dialysis-dependent chronic kidney disease (CKD). However, there is insufficient evidence to recommend a particular type of protein to slow down the CKD progression. Recently, various plant-based diets could demonstrate some additional benefits such as a blood pressure-lowering effect, a reduction of metabolic acidosis as well as hyperphosphatemia, and gut-derived uremic toxins. Furthermore, the former concerns about the risk of undernutrition and hyperkalemia observed with plant-based diets may be inconsistent in real clinical practice. In this review, we summarize the current evidence of the proposed pleiotropic effects of plant-based diets and their associations with clinical outcomes among pre-dialysis CKD patients.

Kidney Function and Physical Performance Decline: The Brain in Kidney Disease (BRINK) Cohort Study.

Rationale & Objective: Patients with kidney failure have poor physical performance, but its trajectory is less clear. We examined physical function over the course of kidney disease, including the transition to dialysis. Study Design: Observational cohort. Setting & Participants: Community-dwelling adults aged ≥45 years in the Brain in Kidney Disease (BRINK) cohort study. Predictors: Estimated glomerular filtration rate (eGFR) and urine albumin to creatinine ratio (UACR). Outcomes: Change in physical performance using the Short Physical Performance Battery (SPPB) (primary) and gait speed (secondary). Analytical Approach: Linear mixed effects regression models. Results: The analytical cohort included 562 participants with mean age of 69.3 (SD, 9.8) years followed for up to 63 months. In total, 49.8% were women. In addition, 79.9% self-identified as White, and 15.3% self-identified as Black. In total, 48.8% had diabetes. Mean eGFR at baseline was 48.1 (SD, 24.3) mL/min/1.73 m2. In unadjusted analysis, lower eGFR was associated with greater decline in SPPB score (P trend < 0.001). The decline in SPPB score was larger among participants with lower eGFR, with a gradient from -0.15 (95% CI, -0.23 to -0.07) points per year for participants with eGFR ≥60 mL/min/1.73 m2 to -0.56 (95% CI, -0.84 to -0.27) for participants with eGFR <15 mL/min/1.73 m2 and -0.61 (95% CI, -0.90 to -0.33) after dialysis initiation. In covariate-adjusted models, SPPB did not continue to decline after dialysis initiation. In secondary analyses evaluating change in gait speed, gait speed continued to decline after dialysis initiation. Higher UACR was also associated with a greater decline in SPPB score and gait speed in unadjusted and adjusted models. Limitations: Small number of participants started dialysis. Conclusions: We found a graded association of chronic kidney disease stage and albuminuria with decline in physical performance. The decline in SPPB was not accelerated after dialysis initiation in covariate-adjusted models, whereas gait speed continued to decline.

Physical function is an important patient-centered outcome in chronic kidney disease (CKD), but whether physical performance changes as kidney disease progresses or when patients start dialysis is not well understood. We found that measures of physical performance, like strength and walking speed, worsened as kidney disease worsened. However, 1 combination of physical performance tests appeared stable (rather than getting worse) after starting dialysis compared to those with very advanced CKD who had not yet started dialysis, while gait speed continued to get worse. This information may help counsel patients who are learning about CKD and considering treatment options. It may also help guide research on interventions to improve physical function in patients with CKD.

Geographic Dialysis Facility Density and Early Dialysis Initiation.

Importance: The decision of when to start maintenance hemodialysis may be affected by health system-level support for high-intensity care as manifested by area dialysis facility density. Yet an association between early hemodialysis initiation and higher area density of dialysis facilities has not been shown. Objective: To examine whether there is an association between area dialysis facility density and earlier dialysis initiation. Design, Setting, and Participants: Cross-sectional analysis was conducted of publicly reported claims and geographic-based population data collected in the Medical Evidence files of the US Renal Data System (USRDS), a comprehensive registry of all patients initiating hemodialysis in the US, from calendar years 2011 through 2019. Data were linked to the American Community Survey, using residential zip codes, and then to health service area (HSA) primary care and hospitalization benchmarks, using the Dartmouth Atlas crosswalk. Data were analyzed from November 1, 2021, to August 31, 2023. Exposure: Dialysis facility density at the level of HSA (number of dialysis facilities per 100 000 HSA residents) split into 5 categories. Main Outcomes and Measures: The odds of hemodialysis initiation at an estimated glomerular filtration rate (eGFR) greater than 10 mL/min/1.73 m2 vs less than or equal to 10 mL/min/1.73 m2. Results: Hemodialysis was initiated in a total of 844 466 individuals at 3397 HSAs at a mean (SD) eGFR of 8.9 (3.8) mL/min/1.73 m2. Their mean (SD) age was 63.5 (14.7) years, and 484 346 participants (57.4%) were men. In the HSA category with the highest facility density, individuals were younger (63.3 vs 65.2 years in least-dense HSAs), poorer (mean percent of households living in poverty, 10.4% vs 8.4%), and more commonly had a higher percentage of Black individuals (40.6% vs 11.3%). More individuals in the dialysis-dense HSAs than least-dense HSAs had diabetes (60.1% vs 58.5%) and fewer had access to predialysis nephrology care (60.8% vs 64.1%); the rates of heart failure and immobility varied, but not in a consistent pattern, by HSA dialysis density. The mean (SD) facility density was 4.1 (1.89) centers per 100 000 population in the most dialysis-dense HSAs. Compared with patients in HSAs with a mean of 1.0 per 100 000 population, the odds of hemodialysis initiation at eGFR greater than 10 mL/min/1.73 m2 were 1.07 (95% CI, 1.03-1.11) for patients in the densest HSAs, and compared with HSAs with 0 facilities, the odds of early hemodialysis initiation were 1.06 (95% CI, 1.02-1.10) for patients in the densest HSAs. Conclusions and Relevance: In this cross-sectional study of USRDS- and HSA-level data, HSA dialysis density was associated with early hemodialysis initiation.

Comparison of outcomes on hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) in anaemia associated with chronic kidney disease: network meta-analyses in dialysis and non-dialysis dependent populations.

Background: Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are oral alternatives to current standard-of-care treatments for anaemia in chronic kidney disease (CKD). We conducted network meta-analyses to indirectly compare clinical outcomes for three HIF-PHIs in dialysis and non-dialysis populations with anaemia in CKD. Methods: The evidence base comprised phase III, randomised, controlled trials evaluating daprodustat, roxadustat, or vadadustat. Three outcomes were evaluated: efficacy [change from baseline in haemoglobin (Hgb)], cardiovascular safety [time to first major adverse cardiovascular event (MACE)] and quality of life [change from baseline in 36-Item Short Form Health Survey (SF-36) Vitality score]. Analyses were performed separately for all patients and for erythropoiesis-stimulating agent (ESA) non-users at baseline (non-dialysis population) or prevalent dialysis patients (dialysis population). Bayesian Markov Chain Monte Carlo methods with non-informative priors were used to estimate the posterior probability distribution and generate pairwise treatment comparisons. Point estimates (medians of posterior distributions) and 95% credible intervals (CrI) were calculated. Results: Seventeen trials were included. In non-dialysis patients, there were no clinically meaningful differences between the three HIF-PHIs with respect to Hgb change from baseline [all patients analysis (total n = 7907): daprodustat vs. roxadustat, 0.09 g/dL (95% CrI -0.14, 0.31); daprodustat vs. vadadustat, 0.09 g/dL (-0.04, 0.21); roxadustat vs. vadadustat, 0.00 g/dL (-0.22, 0.22)] or risk of MACE [all patients analysis (total n = 7959): daprodustat vs. roxadustat, hazard ratio (HR) 1.16 (95% CrI 0.76, 1.77); daprodustat vs. vadadustat, 0.88 (0.71, 1.09); roxadustat vs. vadadustat, 0.76 (0.50, 1.16)]. Daprodustat showed a greater increase in SF-36 Vitality compared with roxadustat [total n = 4880; treatment difference 4.70 points (95% CrI 0.08, 9.31)]. In dialysis patients, Hgb change from baseline was higher with daprodustat and roxadustat compared with vadadustat [all patients analysis (total n = 11 124): daprodustat, 0.34 g/dL (0.22, 0.45); roxadustat, 0.38 g/dL (0.27, 0.49)], while there were no clinically meaningful differences in the risk of MACE between the HIF-PHIs [all patients analysis (total n = 12 320): daprodustat vs. roxadustat, HR 0.89 (0.73, 1.08); daprodustat vs. vadadustat, HR 0.99 (0.82, 1.21); roxadustat vs. vadadustat, HR 1.12 (0.92, 1.37)]. Results were similar in analyses of ESA non-users and prevalent dialysis patients. Conclusions: In the setting of anaemia in CKD, indirect treatment comparisons suggest that daprodustat, roxadustat, and vadadustat are broadly clinically comparable in terms of efficacy and cardiovascular safety (precision was low for the latter), while daprodustat may be associated with reduction in fatigue to a greater extent than roxadustat.

Peritoneal Dialysis Catheter Complications after Insertion by Surgeons, Radiologists, or Nephrologists.

SIGNIFICANCE STATEMENT: The Advancing American Kidney Health Initiative aims to increase rates of utilization of peritoneal dialysis (PD) in the United States. One of the first steps to PD is successful catheter placement, which can be performed by surgeons, interventional radiologists, or nephrologists. We examined the association between operator subspecialty and risk of needing a follow-up procedure in the first 90 days after initial PD catheter implantation. Overall, we found that 15.5% of catheters required revision, removal, or a second catheter placement within 90 days. The odds of requiring a follow-up procedure was 36% higher for interventional radiologists and 86% higher for interventional nephrologists compared with general surgeons. Further research is needed to understand how to optimize the function of catheters across different operator types. BACKGROUND: The US government has implemented incentives to increase the use of PD. Successful placement of PD catheters is an important step to increasing PD utilization rates. Our objective was to compare initial outcomes after PD catheter placement by different types of operators. METHODS: We included PD-naïve patients insured by Medicare who had a PD catheter inserted between 2010 and 2019. We examined the association between specialty of the operator (general surgeon, vascular surgeon, interventional radiologist, or interventional nephrologist) and odds of needing a follow-up procedure, which we defined as catheter removal, replacement, or revision within 90 days of the initial procedure. Mixed logistic regression models clustered by operator were used to examine the association between operator type and outcomes. RESULTS: We included 46,973 patients treated by 5205 operators (71.1% general surgeons, 17.2% vascular surgeons, 9.7% interventional radiologists, 2.0% interventional nephrologists). 15.5% of patients required a follow-up procedure within 90 days of the initial insertion, of whom 2.9% had a second PD catheter implanted, 6.6% underwent PD catheter removal, and 5.9% had a PD catheter revision within 90 days of the initial insertion. In models adjusted for patient and operator characteristics, the odds of requiring a follow-up procedure within 90 days were highest for interventional nephrologists (HR, 1.86; 95% confidence interval [CI], 1.56 to 2.22) and interventional radiologists (odds ratio, 1.36; 95% CI, 1.17 to 1.58) followed by vascular surgeons (odds ratio, 1.06; 95% CI, 0.97 to 1.14) compared with general surgeons. CONCLUSIONS: The probability of needing a follow-up procedure after initial PD catheter placement varied by operator specialty and was higher for interventionalists and lowest for general surgeons.

Muscle Mass and Serum Creatinine Concentration by Race and Ethnicity among Hemodialysis Patients.

SIGNIFICANCE STATEMENT: Serum creatinine is a product of skeletal muscle metabolism. Differences in serum creatinine concentration between Black and non-Black individuals have been attributed to differences in muscle mass but have not been thoroughly examined. Furthermore, other race and ethnic groups have not been considered. If differences in body composition explain differences in serum concentration by race or ethnicity, then estimates of body composition could be used in eGFR equations rather than race. Adjustment for intracellular water (ICW) as a proxy of muscle mass among patients with kidney failure in whom creatinine clearance should minimally influence serum concentration does not explain race- and ethnicity-dependent differences. BACKGROUND: Differences in serum creatinine concentration among groups defined by race and ethnicity have been ascribed to differences in muscle mass. We examined differences in serum creatinine by race and ethnicity in a cohort of patients receiving hemodialysis in whom creatinine elimination by the kidney should have little or no effect on serum creatinine concentration and considered whether these differences persisted after adjustment for proxies of muscle mass. METHODS: We analyzed data from 501 participants in the A Cohort Study to Investigate the Value of Exercise in ESKD/Analyses Designed to Investigate the Paradox of Obesity and Survival in ESKD study who had been receiving hemodialysis for >1 year. We examined the independent associations among race and ethnicity (Black, Asian, non-Hispanic White, and Hispanic), serum creatinine, and ICW (L/m 2 ), a proxy for muscle mass, derived by whole-body multifrequency bioimpedance spectroscopy, using multivariable linear regression with adjustment for several demographic, clinical, and laboratory characteristics. We examined the association of race and ethnicity with serum creatinine concentration with and without adjustment for ICW. RESULTS: Black, Asian, and Hispanic patients had higher serum creatinine concentrations (+1.68 mg/dl [95% confidence interval (CI), 1.09 to 2.27], +1.61 mg/dl [95% CI, 0.90 to 2.32], and +0.83 [95% CI, 0.08 to 1.57], respectively) than non-Hispanic White patients. Overall, ICW was associated with serum creatinine concentration (0.26 mg/dl per L/m 2 ICW; 95% CI, 0.006 to 0.51) but was not statistically significantly different by race and ethnicity. Black, Asian, and Hispanic race and ethnicity remained significantly associated with serum creatinine concentration after adjustment for ICW. CONCLUSION: Among patients receiving dialysis, serum creatinine was higher in Black, Asian, and Hispanic patients than in non-Hispanic White patients. Differences in ICW did not explain the differences in serum creatinine concentration across race groups.

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.

The design and baseline characteristics for the HOPE Consortium Trial to reduce pain and opioid use in hemodialysis.

The HOPE Consortium Trial to Reduce Pain and Opioid Use in Hemodialysis (HOPE Trial) is a multicenter randomized trial addressing chronic pain among patients receiving maintenance hemodialysis for end-stage kidney disease. The trial uses a sequential, multiple assignment design with a randomized component for all participants (Phase 1) and a non-randomized component for a subset of participants (Phase 2). During Phase 1, participants are randomized to Pain Coping Skills Training (PCST), an intervention designed to increase self-efficacy for managing pain, or Usual Care. PCST consists of weekly, live, coach-led cognitive behavioral therapy sessions delivered by video- or tele-conferencing for 12 weeks followed by daily interactive voice response sessions delivered by telephone for an additional 12 weeks. At 24 weeks (Phase 2), participants in both the PCST and Usual Care groups taking prescription opioid medications at an average dose of ≥20 morphine milligram equivalents per day are offered buprenorphine, a partial opioid agonist with a more favorable safety profile than full-agonist opioids. All participants are followed for 36 weeks. The primary outcome is pain interference ascertained, for the primary analysis, at 12 weeks. Secondary outcomes include additional patient-reported measures and clinical outcomes including falls, hospitalizations, and death. Exploratory outcomes include acceptability, tolerability, and efficacy of buprenorphine. The enrollment target of 640 participants was met 27 months after trial initiation. The findings of the trial will inform the management of chronic pain, a common and challenging issue for patients treated with maintenance hemodialysis. NCT04571619.

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.

Associations between abrupt transition, dialysis-requiring AKI, and early mortality in ESKD among U.S. veterans.

BACKGROUND: Mortality is high within the first few months of starting chronic dialysis. Pre-ESKD trajectory of kidney function has been shown to be predictive of early death after dialysis initiation. We aim to better understand how two key aspects of pre-dialysis kidney function-an abrupt transition pattern and an episode of dialysis-requiring AKI (AKI-D) leading directly to ESKD-are associated with early mortality after dialysis initiation. METHODS: We extracted national data from U.S. Veterans Health Administration cross-linked with the United States Renal Data System (USRDS) to identify patients who initiated hemodialysis during 2009-2013. We defined abrupt transition as having a mean outpatient eGFR ≥ 30 ml/min/1.73m2 within 1 year prior to ESKD. AKI-D was identified using inpatient serum creatinine measurements (serum Cr increase by at least 50% from baseline) along with billing codes for inpatient receipt of dialysis for AKI within 30 days prior to the ESKD start date. We used multivariable proportional hazards models to examine the association between patterns of kidney function prior to ESKD and all-cause mortality within 90 days after ESKD. RESULTS: Twenty-two thousand eight hundred fifteen patients were identified in the final analytic cohort of Veterans who initiated hemodialysis and entered the USRDS. We defined five patterns of kidney function decline. Most (68%) patients (N = 15,484) did not have abrupt transition and did not suffer an episode of AKI-D prior to ESKD (reference group). The remaining groups had abrupt transition, AKI-D, or both. Patients who had an abrupt transition with (N = 503) or without (N = 3611) AKI-D had the highest risk of early mortality after ESKD onset after adjustment for demographics and comorbidities (adjusted HR 2.10, 95% CI 1.66-2.65 for abrupt transition with AKI-D; adjusted HR 2.10, 95% CI 1.90-2.33 for abrupt transition without AKI-D). In contrast, patients who experienced AKI-D without an abrupt transition pattern (N = 2141 had only a modestly higher risk of early death (adjusted HR 1.19, 95% CI 1.01-1.40). CONCLUSIONS: An abrupt decline in kidney function within 1 year prior to ESKD occurred in nearly 1 in 5 incident hemodialysis patients (18%) in this national cohort of Veterans and was strongly associated with higher early mortality after ESKD onset.

Unstable Housing and Mortality Among US Veterans Receiving Dialysis.

Importance: Housing status is an important health determinant, yet little is known about unstable housing among individuals receiving dialysis. Objective: To determine factors associated with unstable housing among US veterans receiving dialysis and to estimate the association of unstable housing with risk of death. Design, Setting, and Participants: This retrospective cohort study used data from the US Veterans Health Administration (VHA) and the US Renal Data System for patients who initiated dialysis between October 1, 2012, and December 31, 2018. Veterans were included if they used VHA outpatient services and completed 1 or more unstable housing screenings within a 3-year period before starting dialysis. Data analysis was conducted from January 24 to June 16, 2023. Exposures: Unstable housing was defined as self-report of not having stable housing within the past 2 months or having concerns about stable housing in the next 2 months. Main Outcomes and Measures: The main outcome was all-cause mortality. Characteristics associated with unstable housing at the time of dialysis initiation were examined. The multivariate Fine and Gray cumulative incidence model was used, treating transplant as a competing risk and age as an effect modifier, to examine the risk of death associated with unstable housing. Results: This study included 25 689 veterans, with a median age of 68 (IQR, 62-74) years. Most participants were men (98%), and more than half (52%) were White. There were 771 veterans (3%) with a positive screen for unstable housing within a 3-year period before starting dialysis. Compared with veterans with stable housing, those with unstable housing were younger (mean [SD] age, 61 [8] vs 68 [10] years), were more likely to be Black (45% vs 32%) or Hispanic (9% vs 7%), and were more likely to start dialysis with a central venous catheter (77% vs 66%), receive in-center hemodialysis (96% vs 91%), and have non-Medicare insurance (53% vs 28%). Factors associated with unstable housing included Hispanic ethnicity, non-arteriovenous fistula vascular access, lack of predialysis nephrology care, and non-Medicare insurance. Veterans with unstable housing had higher all-cause mortality (adjusted hazard ratio [AHR], 1.20 [95% CI, 1.04 to 1.37] for a median age of 68 years), and risks increased with age (P = .01 for interaction). In age-stratified analyses, unstable housing was associated with higher mortality among veterans aged 75 to 85 years (AHR, 1.64 [95% CI, 1.18 to 2.28]), but associations were not observed for other age groups. Conclusions and Relevance: In this cohort study of veterans receiving dialysis, unstable housing experienced before starting dialysis was associated with increased risk of all-cause mortality, and risks increased with age. Further efforts are needed to understand the experiences of older adults with unstable housing and to estimate the scope of unstable housing among all individuals receiving dialysis.

Renin-Angiotensin-Aldosterone System Blockade after AKI with or without Recovery among US Veterans with Diabetic Kidney Disease.

SIGNIFICANCE STATEMENT: Among patients with CKD, optimal use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers after AKI is uncertain. Despite these medications' ability to reduce risk of mortality and other adverse outcomes, there is concern that ACEi/ARB use may delay recovery of kidney function or precipitate recurrent AKI. Prior studies have provided conflicting data regarding the optimal timing of these medications after AKI and have not addressed the role of kidney recovery in determining appropriate timing. This study in US Veterans with diabetes mellitus and proteinuria demonstrated an association between ACEi/ARB use and lower mortality. This association was more pronounced with earlier post-AKI ACEi/ARB use and was not meaningfully affected by initiating ACEis/ARBs before versus after recovery from AKI. BACKGROUND: Optimal use of angiotensin-converting enzyme inhibitors (ACEis) or angiotensin II receptor blockers (ARBs) after AKI is uncertain. METHODS: Using data derived from electronic medical records, we sought to estimate the association between ACEi/ARB use after AKI and mortality in US military Veterans with indications for such treatment (diabetes and proteinuria) while accounting for AKI recovery. We used ACEi/ARB treatment after hospitalization with AKI (defined as serum creatinine ≥50% above baseline concentration) as a time-varying exposure in Cox models. The outcome was all-cause mortality. Recovery was defined as return to ≤110% of baseline creatinine. A secondary analysis focused on ACEi/ARB use relative to AKI recovery (before versus after). RESULTS: Among 54,735 Veterans with AKI, 31,146 deaths occurred over a median follow-up period of 2.3 years. Approximately 57% received an ACEi/ARB <3 months after hospitalization. In multivariate analysis with time-varying recovery, post-AKI ACEi/ARB use was associated with lower risk of mortality (adjusted hazard ratio [aHR], 0.74; 95% confidence interval [CI], 0.72 to 0.77). The association between ACEi/ARB use and mortality varied over time, with lower mortality risk associated with earlier initiation ( P for interaction with time <0.001). In secondary analysis, compared with those with neither recovery nor ACEi/ARB use, risk of mortality was lower in those with recovery without ACEi/ARB use (aHR, 0.90; 95% CI, 0.87 to 0.94), those without recovery with ACEi/ARB use (aHR, 0.69; 95% CI, 0.66 to 0.72), and those with ACEi/ARB use after recovery (aHR, 0.70; 95% CI, 0.67 to 0.73). CONCLUSIONS: This study demonstrated lower mortality associated with ACEi/ARB use in Veterans with diabetes, proteinuria, and AKI, regardless of recovery. Results favored earlier ACEi/ARB initiation.

Increased Access, Persistent Disparities: Trends in Disparities in Peritoneal Dialysis (PD) Use, 2009-2019.

Peritoneal dialysis (PD) use has increased in the United States since 2009, but how this has affected disparities in PD use is unclear. We used data from the United States Renal Data System to identify a cohort of incident dialysis patients from 2009 to 2019. We used logistic regression models to examine how odds of PD use changed by demographic characteristics. The incident PD population increased by 203% from 2009 to 2019, and the odds of PD use increased in every subgroup. PD use increased more among older people because the odds for those aged 75 years or older increased 15% more per 5-year period compared with individuals aged 18-44 years (odds ratio [OR] 1.68, 95% confidence interval [CI], 1.64 to 1.73 versus OR 1.46, 95% CI, 1.42 to 1.50). The odds of PD use increased 5% more per 5-year period among Hispanic people compared with White people (OR 1.58, 95% CI, 1.53 to 1.63 versus OR 1.51, 95% CI, 1.48 to 1.53). There was no difference in odds of PD initiation among people who were Black, Asian, or of another race. The odds of PD use increased 5% more for people living in urban areas compared with people living in nonurban areas (5-year OR 1.54, 95% CI, 1.52 to 1.56 versus 5-year OR 1.46, 95% CI, 1.42 to 1.50). The odds of PD use increased 7% more for people living in socioeconomically advantaged areas compared with people living in more deprived areas (5-year OR 1.60, 95% CI, 1.56 to 1.63 for neighborhoods with lowest Social Deprivation Index versus 5-year OR 1.50, 95% CI, 1.48 to 1.53 in the most deprived areas). Expansion of PD use led to a reduction in disparities for older people and for Hispanic people. Although PD use increased across all strata of socioeconomic deprivation, the gap in PD use between people living in the least deprived areas and those living in the most deprived areas widened.