Chronic kidney disease and the global public health agenda: an international consensus

Early detection is a key strategy to prevent kidney disease, its progression and related complications, but numerous studies show that awareness of kidney disease at the population level is low. Therefore, increasing knowledge and implementing sustainable solutions for early detection of kidney disease are public health priorities. Economic and epidemiological data underscore why kidney disease should be placed on the global public health agenda - kidney disease prevalence is increasing globally and it is now the seventh leading risk factor for mortality worldwide. Moreover, demographic trends, the obesity epidemic and the sequelae of climate change are all likely to increase kidney disease prevalence further, with serious implications for survival, quality of life and health care spending worldwide. Importantly, the burden of kidney disease is highest among historically disadvantaged populations that often have limited access to optimal kidney disease therapies, which greatly contributes to current socioeconomic disparities in health outcomes. This joint statement from the International Society of Nephrology, European Renal Association and American Society of Nephrology, supported by three other regional nephrology societies, advocates for the inclusion of kidney disease in the current WHO statement on major non-communicable disease drivers of premature mortality.

Modifiable kidney disease risk factors among nondiabetic adults with obesity from the Multi-Ethnic Study of Atherosclerosis

OBJECTIVE

It is unknown whether weight change or physical fitness is associated with chronic kidney disease (CKD) risk among nondiabetic adults with obesity.

METHODS

This was a prospective, longitudinal cohort study of adults with obesity without baseline CKD or diabetes enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA). Linear mixed-effects and multistate models were adjusted for demographics, time-varying covariates including blood pressure, and comorbidities these were used to examine associations of weight change and slow walking pace (<2 miles/h) with (i) rate of annual estimated glomerular filtration rate (eGFR) decline and (ii) incident CKD, defined as eGFRCr-Cys  < 60 mL/min/1.73 m2 , and tested for interaction by baseline hypertension status.

RESULTS

Among 1208 included MESA participants (median BMI 33.0 kg/m2 [interquartile range 31.2-35.9]), 15% developed CKD. Slow walking pace was associated with eGFR decline (-0.27 mL/min/1.73 m2 /year; 95% CI: -0.42 to -0.12) and CKD risk (adjusted hazard ratio 1.48; 95% CI: 1.08 to 2.01). Weight gain was associated with CKD risk (adjusted hazard ratio 1.34; 95% CI: 1.02 to 1.78 per 5 kg weight gain from baseline). There was no significant interaction by baseline hypertension status.

CONCLUSIONS

Slow walking pace and weight gain were associated with CKD risk among adults with obesity who did not have diabetes at baseline.

Obesity Weight Loss Phenotypes in CKD: Findings From the Chronic Renal Insufficiency Cohort Study

Introduction

Although people with chronic kidney disease (CKD) and obesity have important motivations to lose weight, weight loss is also associated with health risks. We examined whether patterns of change in systolic blood pressure (SBP), serum albumin level, and fat-free mass (FFM) can help to differentiate between healthy and high-risk weight loss in this population.

Methods

Using data from the Chronic Renal Insufficiency Cohort Study (CRIC), we estimated a joint multivariate latent class model with 6 classes to identify distinct trajectories of body mass index (BMI), albumin, and SBP among participants with obesity (BMI ≥30 kg/m2 at baseline), accounting for informative missingness from death. In a secondary analysis, we fit a 6-class model with BMI and FFM.

Results

Among 2831 participants (median baseline BMI 35.6, interquartile range [IQR] 32.4-40.0 kg/m2), median follow-up was 6.8 (IQR 4.8-12.9) years, median age was 61 (IQR 54-67) years, 53% were male, 50% were non-Hispanic Black, and 82% were trying to control or lose weight at baseline. Latent classes were associated with mortality risk (5-year cumulative incidence of mortality 6.8% and 1.5% in class 6 and 3, respectively). Class 6 had the highest mortality rate and was characterized by early, steep BMI loss, early serum albumin decline, and late SBP increase. In the secondary analysis, a class characterized by steep BMI and FFM loss was associated with the highest death risk.

Conclusions

Among adults with CKD and obesity, BMI loss with concomitant serum albumin or FFM loss was associated with a high risk of death.

Post-kidney transplant body mass index trajectories are associated with graft loss and mortality

BACKGROUND

Early post-kidney transplantation (KT) changes in physiology, medications, and health stressors likely impact body mass index (BMI) and likely impact all-cause graft loss and mortality.

METHODS

We estimated 5-year post-KT (n = 151 170; SRTR) BMI trajectories using an adjusted mixed effects model. We estimated long-term mortality and graft loss risks by 1-year BMI change quartile (decrease [1st quartile]: change < -.07 kg/m2 /month; stable [2nd quartile]: -.07 ≤ change ≤ .09 kg/m2 /month; increase [3rd, 4th quartile]: change > .09 kg/m2 /month) using adjusted Cox proportional hazards models.

RESULTS

BMI increased in the 3 years post-KT (.64 kg/m2 /year, 95% CI: .63, .64) and decreased in years 3-5 (-.24 kg/m2 /year, 95% CI: -.26, -.22). 1-year post-KT BMI decrease was associated with elevated risks of all-cause mortality (aHR = 1.13, 95% CI: 1.10-1.16), all-cause graft loss (aHR = 1.13, 95% CI: 1.10-1.15), death-censored graft loss (aHR = 1.15, 95% CI: 1.11-1.19), and mortality with functioning graft (aHR = 1.11, 95% CI: 1.08-1.14). Among recipients with obesity (pre-KT BMI≥30 kg/m2 ), BMI increase was associated with higher all-cause mortality (aHR = 1.09, 95% CI: 1.05-1.14), all-cause graft loss (aHR = 1.05, 95% CI: 1.01-1.09), and mortality with functioning graft (aHR = 1.10, 95% CI: 1.05-1.15) risks, but not death-censored graft loss risks, relative to stable weight. Among individuals without obesity, BMI increase was associated with lower all-cause graft loss (aHR = .97, 95% CI: .95-.99) and death-censored graft loss (aHR = .93, 95% CI: .90-.96) risks, but not all-cause mortality or mortality with functioning graft risks.

CONCLUSIONS

BMI increases in the 3 years post-KT, then decreases in years 3-5. BMI loss in all adult KT recipients and BMI gain in those with obesity should be carefully monitored post-KT.

Deceased-Donor Acute Kidney Injury and Acute Rejection in Kidney Transplant Recipients: A Multicenter Cohort

RATIONALE & OBJECTIVE

Donor acute kidney injury (AKI) activates innate immunity, enhances HLA expression in the kidney allograft, and provokes recipient alloimmune responses. We hypothesized that injury and inflammation that manifested in deceased-donor urine biomarkers would be associated with higher rates of biopsy-proven acute rejection (BPAR) and allograft failure after transplantation.

STUDY DESIGN

Prospective cohort.

SETTING & PARTICIPANTS

862 deceased donors for 1,137 kidney recipients at 13 centers.

EXPOSURES

We measured concentrations of interleukin 18 (IL-18), kidney injury molecule 1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) in deceased donor urine. We also used the Acute Kidney Injury Network (AKIN) criteria to assess donor clinical AKI.

OUTCOMES

The primary outcome was a composite of BPAR and graft failure (not from death). A secondary outcome was the composite of BPAR, graft failure, and/or de novo donor-specific antibody (DSA). Outcomes were ascertained in the first posttransplant year.

ANALYTICAL APPROACH

Multivariable Fine-Gray models with death as a competing risk.

RESULTS

Mean recipient age was 54 ± 13 (SD) years, and 82% received antithymocyte globulin. We found no significant associations between donor urinary IL-18, KIM-1, and NGAL and the primary outcome (subdistribution hazard ratio [HR] for highest vs lowest tertile of 0.76 [95% CI, 0.45-1.28], 1.20 [95% CI, 0.69-2.07], and 1.14 [95% CI, 0.71-1.84], respectively). In secondary analyses, we detected no significant associations between clinically defined AKI and the primary outcome or between donor biomarkers and the composite outcome of BPAR, graft failure, and/or de novo DSA.

LIMITATIONS

BPAR was ascertained through for-cause biopsies, not surveillance biopsies.

CONCLUSIONS

In a large cohort of kidney recipients who almost all received induction with thymoglobulin, donor injury biomarkers were associated with neither graft failure and rejection nor a secondary outcome that included de novo DSA. These findings provide some reassurance that centers can successfully manage immunological complications using deceased-donor kidneys with AKI.

Trends, Social Context, and Transplant Implications of Obesity Among Incident Dialysis Patients in the United States

BACKGROUND

Kidney transplant programs have variable thresholds to accept obese candidates. This study aimed to examine trends and the social context of obesity among United States dialysis patients and implications for kidney transplant access.

METHODS

We performed a retrospective cohort study of 1 084 816 adults who initiated dialysis between January 2007 and December 2016 using the United States Renal Data System data. We estimated national body mass index (BMI) trends and 1-y cumulative incidence of waitlisting and death without waitlisting by BMI category (<18.5 kg/m 2 , ≥18.5 and <25 kg/m 2 [normal weight], ≥25 and <30 kg/m 2 [overweight], ≥30 and <35 kg/m 2 [class 1 obesity], ≥35 and <40 kg/m 2 [class 2 obesity], and ≥40 kg/m 2 [class 3 obesity]). We then used Fine-Gray subdistribution hazard regression models to examine associations between BMI category and 1-y waitlisting with death as a competing risk and tested for effect modification by End Stage Renal Disease (ESRD) network, patient characteristics, and neighborhood social deprivation index.

RESULTS

The median age was 65 (interquartile range 54-75) y, 43% were female, and 27% were non-Hispanic Black. From 2007 to 2016, the adjusted prevalence of class 1 obesity or higher increased from 31.9% to 38.2%. Class 2 and 3 obesity but not class 1 obesity were associated with lower waitlisting rates relative to normal BMI, especially for younger individuals, women, those of Asian race, or those living in less disadvantaged neighborhoods ( pinteraction < 0.001 for all).

CONCLUSIONS

Obesity prevalence is rising among US incident dialysis patients. Relative to normal BMI, waitlisting rates with class 2 and 3 obesity were lower and varied substantially by region, patient characteristics, and socioeconomic context.

Clinically adjudicated deceased donor acute kidney injury and graft outcomes

BACKGROUND

Acute kidney injury (AKI) in deceased donors is not associated with graft failure (GF). We hypothesize that hemodynamic AKI (hAKI) comprises the majority of donor AKI and may explain this lack of association.

METHODS

In this ancillary analysis of the Deceased Donor Study, 428 donors with available charts were selected to identify those with and without AKI. AKI cases were classified as hAKI, intrinsic (iAKI), or mixed (mAKI) based on majority adjudication by three nephrologists. We evaluated the associations between AKI phenotypes and delayed graft function (DGF), 1-year eGFR and GF. We also evaluated differences in urine biomarkers among AKI phenotypes.

RESULTS

Of the 291 (68%) donors with AKI, 106 (36%) were adjudicated as hAKI, 84 (29%) as iAKI and 101 (35%) as mAKI. Of the 856 potential kidneys, 669 were transplanted with 32% developing DGF and 5% experiencing GF. Median 1-year eGFR was 53 (IQR: 41-70) ml/min/1.73m2. Compared to non-AKI, donors with iAKI had higher odds DGF [aOR (95%CI); 4.83 (2.29, 10.22)] and had lower 1-year eGFR [adjusted B coefficient (95% CI): -11 (-19, -3) mL/min/1.73 m2]. hAKI and mAKI were not associated with DGF or 1-year eGFR. Rates of GF were not different among AKI phenotypes and non-AKI. Urine biomarkers such as NGAL, LFABP, MCP-1, YKL-40, cystatin-C and albumin were higher in iAKI.

CONCLUSION

iAKI was associated with higher DGF and lower 1-year eGFR but not with GF. Clinically phenotyped donor AKI is biologically different based on biomarkers and may help inform decisions regarding organ utilization.

Assessment of cerebral oxygenation response to hemodialysis using near-infrared spectroscopy (NIRS): Challenges and solutions

To date, the clinical use of functional near-infrared spectroscopy (NIRS) to detect cerebral ischemia has been largely limited to surgical settings, where motion artifacts are minimal. In this study, we present novel techniques to address the challenges of using NIRS to monitor ambulatory patients with kidney disease during approximately eight hours of hemodialysis (HD) treatment. People with end-stage kidney disease who require HD are at higher risk for cognitive impairment and dementia than age-matched controls. Recent studies have suggested that HD-related declines in cerebral blood flow might explain some of the adverse outcomes of HD treatment. However, there are currently no established paradigms for monitoring cerebral perfusion in real-time during HD treatment. In this study, we used NIRS to assess cerebral hemodynamic responses among 95 prevalent HD patients during two consecutive HD treatments. We observed substantial signal attenuation in our predominantly Black patient cohort that required probe modifications. We also observed consistent motion artifacts that we addressed by developing a novel NIRS methodology, called the HD cerebral oxygen demand algorithm (HD-CODA), to identify episodes when cerebral oxygen demand might be outpacing supply during HD treatment. We then examined the association between a summary measure of time spent in cerebral deoxygenation, derived using the HD-CODA, and hemodynamic and treatment-related variables. We found that this summary measure was associated with intradialytic mean arterial pressure, heart rate, and volume removal. Future studies should use the HD-CODA to implement studies of real-time NIRS monitoring for incident dialysis patients, over longer time frames, and in other dialysis modalities.

Obesity Management in Kidney Transplant Candidates: Current Paradigms and Gaps in Knowledge

In this review, we discuss the increasing prevalence of obesity among people with chronic and end-stage kidney disease (ESKD) and implications for kidney transplant (KT) candidate selection and management. Although people with obesity and ESKD receive survival and quality-of-life benefits from KT, most KT programs maintain strict body mass index (BMI) cutoffs to determine transplant eligibility. However, BMI does not distinguish between visceral adiposity, which confers higher cardiovascular risks and risks of perioperative and adverse posttransplant outcomes, and muscle mass, which is protective in ESKD. Furthermore, requirements for patients with obesity to lose weight before KT should be balanced with the findings of numerous studies that show weight loss is a risk factor for death among patients with ESKD, independent of starting BMI. Data suggest that KT is associated with survival benefits relative to remaining on dialysis for candidates with obesity although recipients without obesity have higher delayed graft function rates and longer transplant hospitalization durations. Research is needed to determine the optimal body composition metrics for KT candidacy assessments and risk stratification. In addition, ESKD-specific obesity management guidelines are needed that will address the neurologic, behavioral, socioeconomic, and physical underpinnings of this increasingly common disease.

Operational challenges in the COVID era: Asymptomatic infections and vaccination timing

The coronavirus disease 2019 (COVID‐19) pandemic has created unprecedented challenges for solid organ transplant programs. While transplant activity has largely recovered, appropriate management of deceased donor candidates who are asymptomatic but have positive nucleic acid testing (NAT) for SARS‐CoV‐2 is unclear, as this result may reflect active infection or prolonged viral shedding. Furthermore, candidates who are unvaccinated or partially vaccinated continue to receive donor offers. In the absence of robust outcomes data, transplant professionals at US adult kidney transplant centers were surveyed (February 13, 2021 to April 29, 2021) to determine community practice (N: 92 centers, capturing 41% of centers and 57% of transplants performed). The majority (97%) of responding centers declined organs for asymptomatic NAT+ patients without documented prior infection. However, 32% of centers proceed with kidney transplant in NAT+ patients who were at least 30 days from initial diagnosis with negative chest imaging. Less than 7% of programs reported inactivating patients who were unvaccinated or partially vaccinated. In conclusion, despite national recommendations to wait for negative testing, many centers are proceeding with kidney transplant in patients with positive SARS‐CoV‐2 NAT results due to presumed viral shedding. Furthermore, few centers are requiring COVID‐19 vaccination prior to transplantation at this time.

Post-transplant Diabetes Mellitus in Kidney Transplant Recipients: A Multicenter Study

Background

De novo post-transplant diabetes mellitus (PTDM) is a common complication after kidney transplant (KT). Most recent studies are single center with various approaches to outcome ascertainment.

Methods

In a multicenter longitudinal cohort of 632 nondiabetic adult kidney recipients transplanted in 2010-2013, we ascertained outcomes through detailed chart review at 13 centers. We hypothesized that donor characteristics, such as sex, HCV infection, and kidney donor profile index (KDPI), and recipient characteristics, such as age, race, BMI, and increased HLA mismatches, would affect the development of PTDM among KT recipients. We defined PTDM as hemoglobin A1c ≥6.5%, pharmacological treatment for diabetes, or documentation of diabetes in electronic medical records. We assessed PTDM risk factors and evaluated for an independent time-updated association between PTDM and graft failure using regression.

Results

Mean recipient age was 52±14 years, 59% were male, 49% were Black. Cumulative PTDM incidence 5 years post-KT was 29% (186). Independent baseline PTDM risk factors included older recipient age (P<0.001) and higher BMI (P=0.006). PTDM was not associated with all-cause graft failure (adjusted hazard ratio (aHR), 1.10; 95% CI, 0.78 to 1.55), death-censored graft failure (aHR, 0.85; 95% CI, 0.53 to 1.37), or death (aHR, 1.31; 95% CI, 0.84 to 2.05) at median follow-up of 6 (interquartile range, 4.0-6.9) years post-KT. Induction and maintenance immunosuppression were not different between patients who did and did not develop PTDM.

Conclusions

PTDM occurred commonly, and higher baseline BMI was associated with PTDM. PTDM was not associated with graft failure or mortality during the 6-year follow-up, perhaps due to the short follow-up time.

Pre-Kidney Transplant Unintentional Weight Loss Leads to Worse Post-Kidney Transplant Outcomes

BACKGROUND

Weight loss before kidney transplant (KT) is a known risk factor for weight gain and mortality; however, whereas unintentional weight loss is a marker of vulnerability, intentional weight loss might improve health. We tested whether pre-KT unintentional and intentional weight loss have differing associations with post-KT weight gain, graft loss, and mortality.

METHODS

Among 919 KT recipients from a prospective cohort study, we used adjusted mixed effects models to estimate post-KT BMI trajectories, and Cox models to estimate death-uncensored graft loss, death-censored graft loss, and all-cause mortality by one-year pre-KT weight change category [stable weight (change≤5%), intentional weight loss (loss>5%), unintentional weight loss (loss>5%), and weight gain (gain>5%)].

RESULTS

Mean age was 53 years, 38% were Black, and 40% were female. In the pre-KT year, 62% of recipients had stable weight, 15% had weight gain, 14% had unintentional weight loss, and 10% had intentional weight loss. In the first three years post-KT, BMI increases were similar among those with pre-KT weight gain and intentional weight loss, and lower compared to those with unintentional weight loss (difference +0.79 kg/m2/year, 95% CI: 0.50-1.08 kg/m2/year, p < 0.001). Only unintentional weight loss was independently associated with higher death-uncensored graft loss (adjusted Hazard Ratio [aHR]=1.80, 95% CI:1.23-2.62), death-censored graft loss (aHR=1.91, 95% CI:1.12-3.26) and mortality (aHR=1.72, 95% CI:1.06-2.79) relative to stable pre-KT weight.

CONCLUSIONS

This study suggests that unintentional, but not intentional, pre-KT weight loss is an independent risk factor for adverse post-KT outcomes.

Living Organ Donor Perspectives and Sources of Hesitancy about COVID-19 Vaccines

BACKGROUND

Living organ donation declined substantially in the United States during the COVID-19 pandemic due to concerns about donor and transplant candidate safety. COVID-19 vaccines might increase confidence in the safety of living organ donation during the pandemic. We assessed informational preferences and perspectives about COVID-19 vaccines among US living organ donors and prospective donors.

METHODS

We conducted a national survey study of organ donors and prospective donors on social media platforms between 12/28/2020-2/23/2021. Survey items included multiple choice, visual analog scale, and open-ended responses. We examined associations between information preferences, history of COVID-19 infection, influenza vaccination history and COVID-19 vaccine acceptance using multivariable logistic regression and performed a thematic analysis of open-ended responses.

RESULTS

Among 342 respondents from 47 US states and the District of Columbia, 35% were between 51-70 years old, 90% were non-Hispanic white, 87% were women; 82% were living donors (94% kidney) and 18% in evaluation to donate (75% kidney).The majority planned to or had received COVID-19 vaccination (76%), whereas 11% did not plan to be receive a vaccine, and 12% were unsure. Adjusting for demographics and donor characteristics, respondents who receive yearly influenza vaccinations had higher COVID-19 vaccine acceptance than those who do not (adjusted Odds Ratio [aOR] 5.06, 95% Confidence Interval [CI] 2.68-9.53). Compared to respondents who prioritized medical information sources (e.g., personal physicians and transplant providers), those who prioritized news and social media had lower COVID-19 vaccine acceptance (aOR 0.34, 95% CI 0.15-0.73). Low perceived personal benefit from vaccination and uncertainty about long-term safety were common themes among those declining COVID-19 vaccines.

CONCLUSIONS

Donor informational source preferences were strongly associated with the likelihood of accepting a COVID-19 vaccine. Vaccine guidance for organ donors who are unsure about COVID-19 vaccines could incorporate messaging about safety and benefits of vaccination for healthy people.

Uromodulin to Osteopontin Ratio in Deceased Donor Urine Is Associated With Kidney Graft Outcomes

BACKGROUND

Deceased-donor kidneys experience extensive injury, activating adaptive and maladaptive pathways therefore impacting graft function. We evaluated urinary donor uromodulin (UMOD) and osteopontin (OPN) in recipient graft outcomes.

METHODS

Primary outcomes: all-cause graft failure (GF) and death-censored GF (dcGF). Secondary outcomes: delayed graft function (DGF) and 6-month estimated glomerular filtration rate (eGFR). We randomly divided our cohort of deceased donors and recipients into training and test datasets. We internally validated associations between donor urine UMOD and OPN at time of procurement, with our primary outcomes. The direction of association between biomarkers and GF contrasted. Subsequently, we evaluated UMOD:OPN ratio with all outcomes. To understand these mechanisms, we examined the effect of UMOD on expression of major histocompatibility complex II in mouse macrophages.

RESULTS

Doubling of UMOD increased dcGF risk (adjusted hazard ratio [aHR], 1.1; 95% confidence interval [CI], 1.02-1.2), whereas OPN decreased dcGF risk (aHR, 0.94; 95% CI, 0.88-1). UMOD:OPN ratio ≤3 strengthened the association, with reduced dcGF risk (aHR, 0.57; 0.41-0.80) with similar associations for GF, and in the test dataset. A ratio ≤3 was also associated with lower DGF (aOR, 0.73; 95% CI, 0.60-0.89) and higher 6-month eGFR (adjusted β coefficient, 3.19; 95% CI, 1.28-5.11). UMOD increased major histocompatibility complex II expression elucidating a possible mechanism behind UMOD's association with GF.

CONCLUSIONS

UMOD:OPN ratio ≤3 was protective, with lower risk of DGF, higher 6-month eGFR, and improved graft survival. This ratio may supplement existing strategies for evaluating kidney quality and allocation decisions regarding deceased-donor kidney transplantation.

Racial disparities in preemptive waitlisting and deceased donor kidney transplantation: Ethics and solutions

Kidney transplantation prior to dialysis, known as "preemptive transplant," enables patients to live longer and avoid the substantial quality of life burdens due to chronic dialysis. Deceased donor kidneys are a public resource that ought to provide health benefits equitably. Unfortunately, White, better educated, and privately insured patients enjoy disproportionate access to preemptive transplantation using deceased donor kidneys. This problem has persisted for decades and is exacerbated by the first-come, first-served approach to kidney allocation for predialysis patients. In this Personal Viewpoint, we describe the diverse barriers to preemptive waitlisting and kidney transplant. The analysis focuses on healthcare system features that particularly disadvantage Black patients, such as the waitlisting eligibility criterion of a single glomerular filtration rate or creatinine clearance ≤20 ml/min, and neglect of wide variation in the rate of progression to end-stage kidney disease (ESKD) in allocating preemptive transplants. We propose initiatives to improve equity including: (1) standardization of waitlisting eligibility criteria related to kidney function; (2) aggressive education for clinicians about early transplant referral; (3) innovations in electronic medical record capabilities; and (4) rapid status 7 listing by centers. If those initiatives fail, the transplant field should consider eliminating preemptive waitlisting and transplantation with deceased donor kidneys.

Contemporary incidence and risk factors of post transplant Erythrocytosis in deceased donor kidney transplantation

BACKGROUND

Post-Transplant erythrocytosis (PTE) has not been studied in large recent cohorts. In this study, we evaluated the incidence, risk factors, and outcome of PTE with current transplant practices using the present World Health Organization criteria to define erythrocytosis. We also tested the hypothesis that the risk of PTE is greater with higher-quality kidneys.

METHODS

We utilized the Deceased Donor Study which is an ongoing, multicenter, observational study of deceased donors and their kidney recipients that were transplanted between 2010 and 2013 across 13 centers. Eryrthocytosis is defined by hemoglobin> 16.5 g/dL in men and> 16 g/dL in women. Kidney quality is measured by Kidney Donor Profile Index (KDPI).

RESULTS

Of the 1123 recipients qualified to be in this study, PTE was observed at a median of 18 months in 75 (6.6%) recipients. Compared to recipients without PTE, those with PTE were younger [mean 48±11 vs 54±13 years, p < 0.001], more likely to have polycystic kidney disease [17% vs 6%, p < 0.001], have received kidneys from younger donors [36 ±13 vs 41±15 years], and be on RAAS inhibitors [35% vs 22%, p < 0.001]. Recipients with PTE were less likely to have received kidneys from donors with hypertension [16% vs 32%, p = 0.004], diabetes [1% vs 11%, p = 0.008], and cerebrovascular event (24% vs 36%, p = 0.036). Higher KDPI was associated with decreased PTE risk [HR 0.98 (95% CI: 0.97-0.99)]. Over 60 months of follow-up, only 17 (36%) recipients had sustained PTE. There was no association between PTE and graft failure or mortality, CONCLUSIONS: The incidence of PTE was low in our study and PTE resolved in majority of patients. Lower KDPI increases risk of PTE. The underutilization of RAAS inhibitors in PTE patients raises the possibility of under-recognition of this phenomenon and should be explored in future studies.

Neighborhood context and kidney disease in Philadelphia

Neighborhood context might influence the risk of chronic kidney disease (CKD), a condition that impacts approximately 10% of the United States population and is associated with significant morbidity, mortality, and costs. We included a sample of 23,692 individuals in Philadelphia, Pennsylvania, who were seen in a large academic primary care practice between January 1, 2016 and December 31, 2017. We used generalized linear equations to estimate the associations between indicators of neighborhood context (e.g., proximity to healthy foods stores, neighborhood walkability, social capital, crime rate, socioeconomic status) and CKD, adjusted for age, sex, race/ethnicity, and insurance coverage. Among those with CKD, secondary outcomes were poor glycemic control (hemoglobin A1c ≥ 6.5%) and uncontrolled blood pressure (systolic ≥ 140 mm Hg and/or diastolic ≥ 90 mm Hg). The cohort represented residents from 97% of Philadelphia census tracts. CKD prevalence was 10%. When all neighborhood context metrics were considered collectively, only lower neighborhood socioeconomic index (a composite assessment of neighborhood income, educational attainment, and occupation) was associated with a higher risk of CKD (lowest tertile vs. highest tertile: adjusted relative risk [aRR] 1.46 [1.25, 1.69]; mid-tertile vs. highest-tertile: aRR 1.35 [1.25, 1.52]). Among those with CKD, compared to residence in the most walkable neighborhoods (i.e., where most essential resources are accessible by foot), residence in neighborhoods with mid-level WalkScore® (i.e., where only some essential neighborhood resources are accessible by foot) was independently associated with poor glycemic control (aRR 1.20, 95% CI 1.01-1.42). These findings suggest a potential role for measures of neighborhood socioeconomic status in identifying communities that would benefit from screening and treatment for CKD. Studies are also needed to determine mechanisms to explain why residence in neighborhoods not easily navigated by foot or car might hinder glycemic control among people with CKD.

An overview of frailty in kidney transplantation: measurement, management and future considerations

The construct of frailty was first developed in gerontology to help identify older adults with increased vulnerability when confronted with a health stressor. This article is a review of studies in which frailty has been applied to pre- and post-kidney transplantation (KT) populations. Although KT is the optimal treatment for end-stage kidney disease (ESKD), KT candidates often must overcome numerous health challenges associated with ESKD before receiving KT. After KT, the impacts of surgery and immunosuppression represent additional health stressors that disproportionately impact individuals with frailty. Frailty metrics could improve the ability to identify KT candidates and recipients at risk for adverse health outcomes and those who could potentially benefit from interventions to improve their frail status. The Physical Frailty Phenotype (PFP) is the most commonly used frailty metric in ESKD research, and KT recipients who are frail at KT (~20% of recipients) are twice as likely to die as nonfrail recipients. In addition to the PFP, many other metrics are currently used to assess pre- and post-KT vulnerability in research and clinical practice, underscoring the need for a disease-specific frailty metric that can be used to monitor KT candidates and recipients. Although frailty is an independent risk factor for post-transplant adverse outcomes, it is not factored into the current transplant program risk-adjustment equations. Future studies are needed to explore pre- and post-KT interventions to improve or prevent frailty.

Survey of US Living Kidney Donation and Transplantation Practices in the COVID-19 Era

INTRODUCTION

The scope of the impact of the coronavirus disease 2019 (COVID-19) pandemic on living donor kidney transplantation (LDKT) practices is not well defined.

METHODS

We surveyed US transplant programs to assess practices, strategies, and barriers to living LDKT during the COVID-19 pandemic. After institutional review board approval, the survey was distributed from 9 May 2020 to 30 May 2020 by e-mail and postings to professional society list-servs. Responses were stratified based on state COVID-19 cumulative incidence levels.

RESULTS

Staff at 118 unique centers responded, representing 61% of US living donor recovery programs and 75% of LKDT volume in the prepandemic year. Overall, 66% reported that LDKT surgery was on hold (81% in "high" vs. 49% in "low" COVID-19 cumulative incidence states). A total of 36% reported that evaluation of new donor candidates had paused, 27% reported that evaluations were very much decreased (>0% to <25% typical), and 23% reported that evaluations were moderately decreased (25% to <50% typical). Barriers to LDKT surgery included program concerns for donor (85%) and recipient (75%) safety, patient concerns (56%), elective case restrictions (47%), and hospital administrative restrictions (48%). Programs with higher local COVID-19 cumulative incidence reported more barriers related to staff and resource diversion. Most centers continuing donor evaluations used remote strategies (video, 82%; telephone, 43%). As LDKT resumes, all programs will screen for COVID-19, although timeframe and modalities will vary. Recommendations for presurgical self-quarantine are also variable.

CONCLUSION

The COVID-19 pandemic has had broad impacts on LDKT practice. Ongoing research and consensus building are needed to reduce barriers, to guide optimal practices, and to support safe restoration of LDKT across centers.

Approaches to Obesity Management in Dialysis Settings: Renal Dietitian Perspectives

OBJECTIVES

Over 40% of individuals in the United States with end-stage kidney disease have obesity. Little is known about renal dietitian perspectives on obesity management in the setting of dialysis dependence.

DESIGN AND METHODS

An online 21-item survey was distributed to 118 renal dietitians via individual outreach and a professional organization e-mail listserv. Four themes were explored: the burden of obesity among dialysis patients, concepts of healthy weight loss, weight loss approaches, and challenges of obesity management in dialysis settings. Respondents were asked to rank approaches and biomarkers for obesity management from 0 (least important or not used) to 100 (most important). Free text fields were provided in each category for additional comments.

RESULTS

Thirty-one renal dietitians responded to the survey (26% response rate). The majority of respondents (90%) indicated that access to kidney transplantation was the main reason that dialysis patients with obesity desired weight loss. Calorie restriction was rated as the most common weight loss approach, and dry weight as the most important weight loss biomarker. Nearly 40% of respondents do not alter their nutritional approach when dialysis patients with obesity are losing weight, and 42% of respondents do not monitor changes in waist circumference. Exercise, diet counseling, and stress management were variably prioritized as weight loss management strategies. Barriers to obesity management in dialysis settings included lack of time, lack of training in weight loss counseling, and gaps in current renal nutritional guidelines.

CONCLUSION

Despite the high prevalence of obesity among individuals with end-stage kidney disease, the results of this survey suggest that current approaches to obesity management in dialysis settings are highly variable. Many renal dietitians lack time to counsel patients on healthy weight loss strategies. Nutritional guidelines are also needed to support people with dialysis dependence and obesity who desire or require weight loss.

Barriers to kidney transplant evaluation in HIV-positive patients with advanced kidney disease: A single-center study

BACKGROUND

HIV-positive kidney transplant (KT) recipients have similar outcomes to HIV-negative recipients. However, HIV-positive patients with advanced kidney disease might face additional barriers to initiating the KT evaluation process. We sought to characterize comorbidities, viral control and management, viral resistance, and KT evaluation appointment rates in a cohort of KT evaluation-eligible HIV-positive patients.

METHODS

We included patients seen between January 1, 2008, and December 31, 2015, at a primary care HIV clinic who met KT evaluation eligibility by an estimated glomerular filtration rate ≤20 mL/min/1.73 meters² or dialysis dependence. The primary outcome was a documented appointment for KT evaluation.

RESULTS

Of 3735 patients evaluated at the HIV primary clinic during the study period, 42 (1.6%) were KT evaluation-eligible patients. The median age was 47 years, 77% were male, and 95%, black. Median CD4 count was 328 cells/mm³ (IQR 175-461). Among the 63% percent with antiretroviral therapy (ART) prescription, 40% had viral loads >200 copies. Among patients with HIV resistance profiles (50%, n = 21), 52% had resistance to at least one class of ART. A majority (60%, n = 25) were scheduled for KT evaluation appointment, but of those, only 8% (n = 2) had evidence of appointments before dialysis dependence. Those without appointments had more schizophrenia (29% vs 4%, P = .02), resistance (78% vs 33%, P = .04), ART prescription (76% vs 48%, P = .04), and more kidney disease of unknown etiology (53% vs 8%, P = .02).

CONCLUSION

Kidney transplant evaluation-eligible HIV-positive patients had a high rate of evaluation appointments, but a low rate of preemptive evaluation appointments. Schizophrenia and viral resistance disproportionally affected patients without evaluation appointments. These data precede the recommendation for universal ART for all HIV+ patients, regardless of CD4 count and viral load, and must be interpreted in the context of this limitation.

Perceptions and Practices Regarding Frailty in Kidney Transplantation: Results of a National Survey

BACKGROUND

Given the potential utility of frailty, a clinical phenotype of decreased physiologic reserve and resistance to stressors, to predict postkidney transplant (KT) outcomes, we sought to understand the perceptions and practices regarding frailty measurement in US KT programs.

METHODS

Surveys were emailed to American Society of Transplantation Kidney/Pancreas Community of Practice members and 202 US transplant programs (November 2017 to April 2018). Program characteristics were gleaned from Scientific Registry of Transplant Recipients.

RESULTS

The 133 responding programs (response rate = 66%) represented 77% of adult KTs and 79% of adult KT candidates in the United States. Respondents considered frailty to be a useful concept in evaluating candidacy (99%) and endorsed a need to develop a frailty measurement specific to KT (92%). Frailty measurement was more common during candidacy evaluation (69%) than during KT admission (28%). Of the 202 programs, 38% performed frailty assessments in all candidates while 23% performed assessments only for older candidates. There was heterogeneity in the frailty assessment method; 18 different tools were utilized to measure frailty. The most common tool was a timed walk test (19%); 67% reported performing >1 tool. Among programs that measure frailty, 53% reported being less likely to list frail patients for KT.

CONCLUSIONS

Among US KT programs, frailty is recognized as a clinically relevant construct and is commonly measured at evaluation. However, there is considerable heterogeneity in the tools used to measure frailty. Efforts to identify optimal measurement of frailty using either an existing or a novel tool and subsequent standardization of its measurement and application across KT programs should be considered.

Safety and Efficacy of Universal Postoperative Decolonization for Kidney Transplant Recipients

OBJECTIVES

Infection is a common cause of morbidity and mortality after kidney transplant. Based on the well-documented successes of reducing infections with decolonization of patients in intensive care units, we began a universal immediate posttransplant decolonization program for all kidney transplant recipients. Herein, we report safety and efficacy of this decolonization program.

MATERIALS AND METHODS

We compared a consecutive cohort of kidney transplant recipients who underwent universal decolonization (intervention group) with a cohort of transplant patients from an era immediately prior to this practice (control group). Universal decolonization included daily chlorhexidine body wash and nasal mupirocin ointment.

RESULTS

Seventy-eight patients who underwent universal decolonization were compared with 43 patients in the control group. Ten microbiologically proven infections (8.3%) occurred in the 30 days after discharge: 7 (9%) in the intervention group and 3 (7%) in the control group. Forty-five transplant recipients (37.2%) were readmitted in the 30 days after discharge: 31 (39.7%) in the intervention group and 14 (32.6%) in the control group. No patients in the intervention group had adverse drug events from mupirocin and chlorhexidine use.

CONCLUSIONS

A universal decolonization protocol was successfully implemented and was well tolerated by all patients. Despite successful implementation, we did not observe any significant differences in infection rates between treated patients and historical controls.

Report from the American Society of Transplantation on frailty in solid organ transplantation

A consensus conference on frailty in kidney, liver, heart, and lung transplantation sponsored by the American Society of Transplantation (AST) and endorsed by the American Society of Nephrology (ASN), the American Society of Transplant Surgeons (ASTS), and the Canadian Society of Transplantation (CST) took place on February 11, 2018 in Phoenix, Arizona. Input from the transplant community through scheduled conference calls enabled wide discussion of current concepts in frailty, exploration of best practices for frailty risk assessment of transplant candidates and for management after transplant, and development of ideas for future research. A current understanding of frailty was compiled by each of the solid organ groups and is presented in this paper. Frailty is a common entity in patients with end-stage organ disease who are awaiting organ transplantation, and affects mortality on the waitlist and in the posttransplant period. The optimal methods by which frailty should be measured in each organ group are yet to be determined, but studies are underway. Interventions to reverse frailty vary among organ groups and appear promising. This conference achieved its intent to highlight the importance of frailty in organ transplantation and to plant the seeds for further discussion and research in this field.

The Value of Anthropometric Measures in Nutrition and Metabolism: Comment on Anthropometrically Predicted Visceral Adipose Tissue and Blood-Based Biomarkers: A Cross-Sectional Analysis

Visceral adipose tissue (VAT)—fat stored deep in the abdominal cavity that surrounds vital organs—is associated with a variety of chronic health conditions. Computed tomography and magnetic resonance imaging are the gold standards to quantify VAT. However, the high cost, limited accessibility, and potential exposure to radiation limit the use of these imaging modalities. In this commentary, we review the application of a previously validated regression equation that estimates anthropometrically predicted VAT (apVAT) to explain variance in blood-based biomarkers and predict mortality in a large sample of adults. In our first study (Brown et al. 2018 Eur J Nutr; doi:10.1007/s00394-016-1308-8), apVAT accounted for more variance in biomarkers of glucose homeostasis, inflammation, and lipid metabolism, than body mass index (BMI), waist circumference (WC), or the combination of BMI + WC. In our second study (Brown et al. 2017 Am J Hum Biol; doi:10.1002/ajhb.22898), compared with BMI, WC, and BMI + WC, apVAT more accurately predicted mortality from all causes, cardiovascular disease, and cancer. These studies demonstrate that apVAT can be used in clinical practice and in clinical nutrition and metabolism research when imaging modalities to quantify VAT may not be feasible.

Epidemiology of prediabetes and diabetes in Namibia, Africa: A multilevel analysis

BACKGROUND

Diabetes is a leading cause of progressive morbidity and early mortality worldwide. Little is known about the burden of diabetes and prediabetes in Namibia, a Sub-Saharan African (SSA) country that is undergoing a demographic transition.

METHODS

We estimated the prevalence and correlates of diabetes (defined as fasting [capillary] blood glucose [FBG] ≥126 mg/dL) and prediabetes (defined by World Health Organization [WHO] and American Diabetes Association [ADA] criteria as FBG 110-125 and 100-125 mg/dL, respectively) in a random sample of 3278 participants aged 35-64 years from the 2013 Namibia Demographic and Health Survey.

RESULTS

The prevalence of diabetes was 5.1% (95% confidence interval [CI]: 4.2-6.2), with no evidence of gender differences (P = 0.45). The prevalence of prediabetes was 6.8% (95% CI 5.8-8.0) using WHO criteria and 20.1% (95% CI 18.4-21.9) using ADA criteria. Male sex, older age, higher body mass index (BMI), and occupation independently increased the odds of diabetes in Namibia, whereas higher BMI was associated with a higher odds of prediabetes, and residing in a household categorized as "middle wealth index" was associated with a lower odds of prediabetes (adjusted odds ratio 0.71; 95% credible interval 0.46-0.99). There was significant clustering of prediabetes and diabetes at the community level.

CONCLUSIONS

One in five adult Namibians has prediabetes based on ADA criteria. Resources should be invested at the community level to promote efforts to prevent the progression of this disease and its complications.

Deceased-donor acute kidney injury is not associated with kidney allograft failure

Deceased-donor acute kidney injury (AKI) is associated with organ discard and delayed graft function, but data on longer-term allograft survival are limited. We performed a multicenter study to determine associations between donor AKI (from none to severe based on AKI Network stages) and all-cause graft failure, adjusting for donor, transplant, and recipient factors. We examined whether any of the following factors modified the relationship between donor AKI and graft survival: kidney donor profile index, cold ischemia time, donation after cardiac death, expanded-criteria donation, kidney machine perfusion, donor-recipient gender combinations, or delayed graft function. We also evaluated the association between donor AKI and a 3-year composite outcome of all-cause graft failure or estimated glomerular filtration rate ≤ 20 mL/min/1.73 m² in a subcohort of 30% of recipients. Among 2,430 kidneys transplanted from 1,298 deceased donors, 585 (24%) were from donors with AKI. Over a median follow-up of 4.0 years, there were no significant differences in graft survival by donor AKI stage. We found no evidence that pre-specified variables modified the effect of donor AKI on graft survival. In the subcohort, donor AKI was not associated with the 3-year composite outcome. Donor AKI was not associated with graft failure in this well-phenotyped cohort. Given the organ shortage, the transplant community should consider measures to increase utilization of kidneys from deceased donors with AKI.

Association of the kidney allocation system with dialysis exposure before deceased donor kidney transplantation by preemptive wait-listing status

BACKGROUND

It is unknown whether the new kidney transplant allocation system (KAS) has attenuated the advantages of preemptive wait-listing as a strategy to minimize pretransplant dialysis exposure.

METHODS

We performed a retrospective study of adult US deceased donor kidney transplant (DDKT) recipients between December 4, 2011-December 3, 2014 (pre-KAS) and December 4, 2014-December 3, 2017 (post-KAS). We estimated pretransplant dialysis durations by preemptive listing status in the pre- and post-KAS periods using multivariable gamma regression models.

RESULTS

Among 65 385 DDKT recipients, preemptively listed recipients (21%, n = 13 696) were more likely to be white (59% vs 34%, P < 0.001) and have private insurance (64% vs 30%, P < 0.001). In the pre- and post-KAS periods, average adjusted pretransplant dialysis durations for preemptively listed recipients were <2 years in all racial groups. Compared to recipients who were listed after starting dialysis, preemptively listed recipients experienced 3.85 (95% Confidence Interval [CI] 3.71-3.99) and 4.53 (95% CI 4.32-4.74) fewer average years of pretransplant dialysis in the pre- and post-KAS periods, respectively (P < 0.001 for all comparisons).

CONCLUSIONS

Preemptively wait-listed DDKT recipients continue to experience substantially fewer years of pretransplant dialysis than recipients listed after dialysis onset. Efforts are needed to improve both socioeconomic and racial disparities in preemptive wait-listing.

Self-reported major mobility disability and mortality among cancer survivors

OBJECTIVE

To quantify the prevalence of self-reported major mobility disability (SR-MMD) and its association with mortality in a nationally-representative sample of cancer survivors.

MATERIALS AND METHODS

This study included patients with a history of cancer who participated in the National Health and Nutrition Examination Survey 19992010. SR-MMD was defined as self-reported difficulty or inability to walk a quarter of a mile. Vital status through December 15, 2011 was ascertained from the United States National Center for Health Statistics. Multivariable-adjusted Cox regression models were used to quantify the hazard ratio (HR) and 95% confidence interval (CI) between SR-MMD and mortality.

RESULTS

The study included 1458 cancer survivors who averaged 67.1 years of age. At baseline, 201 (13.7%) participants had SR-MMD. During a median follow-up of 4.7 years, 434 (29.8%) participants died. SR-MMD was independently associated with a higher risk of all-cause mortality [HR: 2.15 (95% CI: 1.56-2.97); P < 0.001] and cancer-specific mortality [HR: 2.49 (95% CI: 1.53-4.07); P < 0.001]. The association between SR-MMD and all-cause mortality was not modified by age, sex, time since cancer diagnosis, body mass index, or comorbid health conditions.

CONCLUSION

SR-MMD is an easily ascertainable metric of physical function that is associated with a higher risk of mortality among cancer survivors. Integrating measures of physical function may help to guide clinical decision-making and improve long-term prognostication in this population. Interventions that prevent the development of SR-MDD, such as physical activity, should be evaluated in this population.

Association between Medicaid Expansion under the Affordable Care Act and Preemptive Listings for Kidney Transplantation

BACKGROUND AND OBJECTIVES

Before 2014, low-income individuals in the United States with non-dialysis-dependent CKD had fewer options to attain health insurance, limiting their opportunities to be preemptively wait-listed for kidney transplantation. We examined whether expanding Medicaid under the Affordable Care Act was associated with differences in the number of individuals who were pre-emptively wait-listed with Medicaid coverage.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using the United Network of Organ Sharing database, we performed a retrospective observational study of adults (age≥18 years) listed for kidney transplantation before dialysis dependence between January 1, 2011-December 31, 2013 (pre-Medicaid expansion) and January 1, 2014-December 31, 2016 (post-Medicaid expansion). In multinomial logistic regression models, we compared trends in insurance types used for pre-emptive wait-listing in states that did and did not expand Medicaid with a difference-in-differences approach.

RESULTS

States that fully implemented Medicaid expansion on January 1, 2014 ("expansion states," n=24 and the District of Columbia) had a 59% relative increase in Medicaid-covered pre-emptive listings from the pre-expansion to postexpansion period (from 1094 to 1737 listings), compared with an 8.8% relative increase (from 330 to 359 listings) among 19 Medicaid nonexpansion states (P<0.001). From the pre- to postexpansion period, the adjusted proportion of listings with Medicaid coverage decreased by 0.3 percentage points among nonexpansion states (from 4.0% to 3.7%, P=0.09), and increased by 3.0 percentage points among expansion states (from 7.0% to 10.0%, P<0.001). Medicaid expansion was associated with absolute increases in Medicaid coverage by 1.4 percentage points among white listings, 4.0 percentage points among black listings, 5.9 percentage points among Hispanic listings, and 5.3 percentage points among other listings (P<0.001 for all comparisons).

CONCLUSIONS

Medicaid expansion was associated with an increase in the proportion of new pre-emptive listings for kidney transplantation with Medicaid coverage, with larger increases in Medicaid coverage among racial and ethnic minority listings than among white listings.

Cognitive Impairment in Non-Dialysis-Dependent CKD and the Transition to Dialysis: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

BACKGROUND

Advanced chronic kidney disease is associated with elevated risk for cognitive impairment. However, it is not known whether and how cognitive impairment is associated with planning and preparation for end-stage renal disease.

STUDY DESIGN

Retrospective observational study.

SETTING & PARTICIPANTS

630 adults participating in the CRIC (Chronic Renal Insufficiency Cohort) Study who had cognitive assessments in late-stage CKD, defined as estimated glome-rular filtration rate ≤ 20mL/min/1.73m², and subsequently initiated maintenance dialysis therapy.

PREDICTOR

Predialysis cognitive impairment, defined as a score on the Modified Mini-Mental State Examination lower than previously derived age-based threshold scores. Covariates included age, race/ethnicity, educational attainment, comorbid conditions, and health literacy.

OUTCOMES

Peritoneal dialysis (PD) as first dialysis modality, preemptive permanent access placement, venous catheter avoidance at dialysis therapy initiation, and preemptive wait-listing for a kidney transplant.

MEASUREMENTS

Multivariable-adjusted logistic regression.

RESULTS

Predialysis cognitive impairment was present in 117 (19%) participants. PD was the first dialysis modality among 16% of participants (n=100), 75% had preemptive access placed (n=473), 45% avoided using a venous catheter at dialysis therapy initiation (n=279), and 20% were preemptively wait-listed (n=126). Predialysis cognitive impairment was independently associated with 78% lower odds of PD as the first dialysis modality (adjusted OR [aOR], 0.22; 95% CI, 0.06-0.74; P=0.02) and 42% lower odds of venous catheter avoidance at dialysis therapy initiation (aOR, 0.58; 95% CI, 0.34-0.98; P=0.04). Predialysis cognitive impairment was not independently associated with preemptive permanent access placement or wait-listing.

LIMITATIONS

Potential unmeasured confounders; single measure of cognitive function.

CONCLUSIONS

Predialysis cognitive impairment is associated with a lower likelihood of PD as a first dialysis modality and of venous catheter avoidance at dialysis therapy initiation. Future studies may consider addressing cognitive function when testing strategies to improve patient transitions to dialysis therapy.

Kidney Transplantation in HIV-Positive Patients: A Single-Center, 16-Year Experience

Hahnemann University Hospital has performed 120 kidney transplantations in human immunodeficiency virus (HIV)-positive individuals during the last 16 years. Our patient population represents ∼10% of the entire US population of HIV-positive kidney recipients. In our earlier years of HIV transplantation, we noted increased rejection rates, often leading to graft failure. We have established a multidisciplinary team and over the years have made substantial protocol modifications based on lessons learned. These modifications affected our approach to candidate evaluation, donor selection, perioperative immunosuppression, and posttransplantation monitoring and resulted in excellent posttransplantation outcomes, including 100% patient and graft survival at 1 year and patient and graft survival at 3 years of 100% and 96%, respectively. We present key clinical data, including a granular patient-level analysis of the associations of antiretroviral therapy regimens with long-term survival, cellular and antibody-mediated rejection rates, and the causes of allograft failures. In summary, we provide details on the evolution of our approach to HIV transplantation during the last 16 years, including strategies that may improve outcomes among HIV-positive kidney transplantation candidates throughout the United States.

Barriers to listing for HIV-infected patients being evaluated for kidney transplantation

Human immunodeficiency virus (HIV)-infected patients have excellent outcomes following kidney transplantation (KT) but still might face barriers in the evaluation and listing process. The aim of this study was to characterize the patient population, referral patterns, and outcomes of HIV-infected patients who present for KT evaluation. We performed a single-center retrospective cohort study of HIV-infected patients who were evaluated for KT. The primary outcome was time to determination of eligibility for KT. Between 2011 and 2015, 105 HIV-infected patients were evaluated for KT. Of the 105 patients, 73 were listed for transplantation by the end of the study period. For those who were deemed ineligible, the most common reasons cited were active substance abuse (n = 7, 22%) and failure to complete the full transplant evaluation (n = 7, 22%). Our cohort demonstrated a higher proportion of HIV-infected patients eligible for KT than in previous studies, likely secondary to advances in HIV management. Among those who were denied access to transplantation, we identified that many were unable to complete the evaluation process, and that active substance abuse was common. Future prospective studies should examine reasons and potential interventions for the lack of follow-through and drug use we observed in this population.

Association of tenofovir disoproxil fumarate with primary allograft survival in HIV-positive kidney transplant recipients

BACKGROUND

Tenofovir disoproxil fumarate (TDF) is an antiretroviral agent frequently used to treat human immunodeficiency virus (HIV). There are concerns regarding its potential to cause acute kidney injury, chronic kidney disease, and proximal tubulopathy. Although TDF can effectively suppress HIV after kidney transplantation, it is unknown whether use of TDF-based antiretroviral therapy (ART) after kidney transplantation adversely affects allograft survival.

METHODS

We examined 104 HIV+ kidney transplant (KT) recipients at our center between 2001 and 2014. We generated a propensity score for TDF treatment using recipient and donor characteristics. We then fit Cox proportional hazards models to investigate the association between TDF treatment and 3-year, death-censored primary allograft failure, adjusting for the propensity score and delayed graft function (DGF).

RESULTS

Of the 104 HIV+ KT candidates who underwent transplantation during the study period, 23 (22%) were maintained on TDF-based ART at the time of transplantation, and 81 (78%) were on non-TDF-based ART. Median age of the cohort was 48 years; 87% were male; 88% were black; and median CD4 count at transplantation was 450 cells/mm³ . Median kidney donor risk index was 1.2. At 3 years post transplantation, primary allograft failure occurred in 26% of patients on TDF-based ART and in 28% of patients on non-TDF-based ART (P=.5). TDF treatment was not associated with primary allograft failure at 3 years post transplant after adjusting for DGF and a propensity score for TDF use (hazard ratio 2.12, 95% confidence interval 0.41-10.9).

CONCLUSIONS

In a large single-center experience of HIV+ kidney transplantation, TDF use following kidney transplantation was not significantly associated with primary allograft failure. These results may help inform management for HIV+ KT recipients in need of TDF therapy for adequate viral suppression.

Nonalcoholic fatty liver disease and mortality among cancer survivors

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) may foster a tumor microenvironment that promotes cancer recurrence and progression. We examined the relationship between NAFLD and mortality among a sample of cancer survivors.

METHODS

Ultrasonography was used to assess hepatic steatosis, and standardized algorithms were used to define NAFLD. Study endpoints included all-cause, cancer-specific, and cardiovascular-specific mortality.

RESULTS

Among 387 cancer survivors, 17.6% had NAFLD. During a median of 17.9 years of follow up, we observed 196 deaths from all causes. In multivariable-adjusted regression models, NAFLD was associated with an increased risk of all-cause mortality [HR: 2.52, 95% CI: 1.47-4.34; P=0.001]. We observed 86 cancer-specific deaths. In multivariable-adjusted regression models, NAFLD was associated with an increased risk of cancer-specific mortality [HR: 3.21, 95% CI: 1.46-7.07; P=0.004]. We observed 46 cardiovascular-specific deaths. In multivariable-adjusted regression models, NAFLD was not associated with an increased risk of cardiovascular-specific mortality [HR: 1.04, 95% CI: 0.30-3.64, P=0.951].

CONCLUSION

NAFLD is associated with an increased risk of all-cause and cancer-specific mortality among cancer survivors. This novel observation warrants replication. Evaluating the efficacy of interventions, such as lifestyle modification through weight loss and exercise, to improve NAFLD in this population may be considered.

Identification of Risk Factors Associated With Clostridium difficile Infection in Liver Transplantation Recipients: A Single-Center Analysis

Clostridium difficile remains the leading cause of health care-associated infectious diarrhea, and its incidence and severity are increasing in liver transplant recipients. Several known risk factors for C difficile infection (CDI) are inherently associated with liver transplantation, such as severe underlying illness, immunosuppression, abdominal surgery, and broad-spectrum antibiotic use. We conducted a single-center retrospective case control study to characterize risk factors for CDI among patients who received a liver transplant from January 2008 to December 2012. We also examined the associations of post-transplantation CDI with transplant outcomes. Cases were defined as having diarrhea with a positive test for C difficile by either toxin A/B enzyme immunoassay (EIA) or glutamate dehydrogenase EIA and polymerase chain reaction within 1 year after transplantation. Sixty-five consecutive patients were evaluated, of which 15 (23%) developed CDI. The median time from transplantation to CDI diagnosis was 65 days (interquartile range [IQR] 13-208) and more than one-half (53%) had severe infection. Risk factors that were associated with CDI among liver transplant recipients included: (1) previous history of CDI (20% vs 0%; P = .001); (2) exposure to proton-pump inhibitor therapy (93% vs 60%; P = .015); (3) antimicrobial therapy before transplantation (47% vs 18%; P = .039); (4) a prolonged length of stay before transplantation (1 day [IQR, 1-19] vs 1 day [IQR, 0-1]; P = .028); and (5) chronic kidney disease (53% vs 20%; P = .011). There was no significant differences in patient survivals at 6 months (93% vs 96%; P = .67) and 12 months (87% vs 94%; P = .35) among CDI case and control subjects, respectively.

Physical activity, diet quality, and mortality among sarcopenic older adults

BACKGROUND

It is unknown if physical activity and good diet quality modify the risk of poor outcomes, such as mortality, among older adults with sarcopenia.

AIM

To examine if physical activity and good diet quality modify the risk of poor outcomes, such as mortality, among older adults with sarcopenia.

METHODS

A population-based cohort study among 1618 older adults with sarcopenia from the Third National Health and Nutrition Survey (NHANES III; 1988-1994). Sarcopenia was defined by the European Working Group on Sarcopenia in Older People. Physical activity was self-reported, and classified as sedentary (0 bouts per week), physically inactive (1-4 bouts per week), and physically active (≥5 bouts per week). Diet quality was assessed with the healthy eating index (a scale of 0-100 representing adherence to federal dietary recommendations), and classified as poor (<51), fair (51-80), and good (>80) diet quality.

RESULTS

Compared to participants who were sedentary, those who were physically inactive were 16 % less likely to die [HR 0.84 (95 % CI 0.64-1.09)], and those who were physically active were 25 % less likely to die [HR 0.75 (95 % CI 0.59-0.97); P _trend = 0.026]. Compared to participants with poor diet quality, those with fair diet quality were 37 % less likely to die [HR 0.63 (95 % CI 0.47-0.86)], and those with good diet quality were 45 % less likely to die [HR 0.55 (95 % CI 0.37-0.80); P _trend = 0.002].

CONCLUSIONS

Participation in physical activity and consumption of a healthy diet correspond with a lower risk of mortality among older adults with sarcopenia. Randomized trials are needed in this population.

Appendicular Lean Mass and Mortality among Prefrail and Frail Older Adults

OBJECTIVE

Prefrail and frail older adults are a heterogeneous population. The measurement of appendicular lean mass (ALM) may distinguish those at higher versus lower risk of poor outcomes. We examined the relationship between ALM and mortality among prefrail and frail older adults.

DESIGN

This was a population-based cohort study.

SETTING

The Third National Health and Nutrition Survey (NHANES III; 1988-1994).

PARTICIPANTS

Older adults (age ≥65 years) with pre-frailty or frailty defined using the Fried criteria.

MEASUREMENTS

ALM was quantified using bioimpedance analysis. Multivariable-adjusted Cox regression analysis examined the relationship between ALM and mortality. Logistic regression analysis was used to determine if ALM added to age and sex improved the predictive discrimination of five-year and ten-year mortality.

RESULTS

At baseline, the average age was 74.9 years, 66.7% were female, 86.3% and 13.7% were prefrail and frail, respectively. The mean ALM was 18.9 kg [standard deviation (SD): 5.5]. During a median 8.9 years of follow-up, 1,307 of 1,487 study participants died (87.9%). Higher ALM was associated with a lower risk of mortality. In a multivariable-adjusted regression model that accounted for demographic, behavioral, clinical, physical function, and frailty characteristics, each SD increase in ALM was associated with an 50% lower risk of mortality [Hazard Ratio: 0.50 (95% CI: 0.27-0.92); P=0.026]. The addition of ALM to age and sex improved the predictive discrimination of five-year (P=0.027) and ten-year (P=0.016) mortality.

CONCLUSION

ALM distinguishes the risk of mortality among prefrail and frail older adults. Additional research examining ALM as a therapeutic target is warranted.

Physical Activity, Diet Quality, and Mortality among Community-Dwelling Prefrail and Frail Older Adults

It is unknown if physical activity and diet quality are associated with the risk of poor outcomes, such as mortality, among prefrail and frail older adults. This was a population-based cohort study among 1487 prefrail and frail older-adults from the Third National Health and Nutrition Survey. Compared to participants who were sedentary (0 bouts of physical activity per week), those who were physically inactive (1-4 bouts of physical activity per week) were 24% less likely to die [HR: 0.76 (95% CI: 0.58-0.98)], and those who were physically active (≥5 bouts of physical activity per week) were 34% less likely to die [HR: 0.66 (95% CI: 0.51-0.86); Ptrend = 0.002]. Compared to participants with poor diet quality, those with fair diet quality were 26% less likely to die [HR: 0.74 (95% CI: 0.52-0.98)], and those with good diet quality were 33% less likely to die [HR: 0.67 (95% CI: 0.55-1.00); Ptrend = 0.050]. There was a synergistic interaction between physical activity and diet quality on the risk of mortality (Pinteraction = 0.058). Participation in physical activity and consumption of a healthy diet is associated with a lower risk of mortality among prefrail and frail older adults.

The muscle quality index and mortality among males and females

PURPOSE

The muscle quality index (MQI) was proposed as a measure to quantify age-related alterations in muscle function. It is unknown if the MQI predicts mortality.

METHODS

This was a population-based cohort study from the Third National Health and Nutrition Survey (NHANES III; 1988-1994). The MQI was quantified using a timed sit-to-stand test, body mass, and leg length. Vital status was obtained through the National Center for Health Statistics. We fit multivariable-adjusted regression models to estimate the hazard ratio (HR) and 95% confidence interval (CI) between the MQI and mortality.

RESULTS

During 14.6 years of follow-up, 3299 (73.1%) of 4510 study participants died. Lower MQI was associated with a higher risk of mortality (Ptrend <.001). The multivariable-adjusted HR for mortality was 1.50 (95% CI, 1.15-1.96) for those in the lowest quintile of MQI compared to the highest quintile. The association between MQI and mortality was stronger among males (highest vs. lowest quintile of MQI, HR = 1.37 [95% CI, 1.00-1.87]; Ptrend = .001) compared to females (highest vs. lowest quintile of MQI, HR = 1.27 (95% CI, 0.89-1.83); Ptrend = .044; Pinteraction = .005].

CONCLUSIONS

The MQI predicts mortality and may differ between males and females. Additional research examining the MQI is warranted.

Anthropometrically-predicted visceral adipose tissue and mortality among men and women in the third national health and nutrition examination survey (NHANES III)

OBJECTIVE

This study seeks to quantify the relationship between anthropometrically-predicted visceral adipose tissue (apVAT) and all-cause and cause-specific mortality among individuals of European descent in a population-based prospective cohort study of 10,624 participants.

METHODS

The apVAT with a validated regression equation that included age, body mass index, and waist and thigh circumferences were predicted.

RESULTS

During a median of 18.8 years, 3531 participants died with 1153 and 741 deaths attributable to cardiovascular disease and cancer, respectively. In multivariable-adjusted analyses that accounted for demographic, clinical, and behavioral characteristics, higher apVAT was associated with an increased risk of all-cause (P_trend  < .001), cardiovascular-specific (P_trend  < .001), and cancer-specific mortality (P_trend  = .007). Excluding participants with a history of cancer, myocardial infarction, heart failure, or diabetes at baseline did not substantively alter effect estimates. apVAT more accurately predicted all-cause, cardiovascular-specific, and cancer-specific mortality than body mass index (P < .001), waist circumference (P < .001), or the combination of body mass index and waist circumference (P < .001).

CONCLUSIONS

These data provide evidence that apVAT is associated with all-cause and cause-specific mortality in a large population-based sample of men and women of European descent. These results support the use of apVAT to risk-stratify individuals for premature mortality when imaging data are not available such as in routine clinical practice or in large clinical trials.

Serum creatinine elevation after switch to dolutegravir in a human immunodeficiency virus-positive kidney transplant recipient

Dolutegravir is a preferred antiretroviral drug for human immunodeficiency virus (HIV)-infected patients following solid organ transplantation. It has potent antiretroviral activity and does not interact with calcineurin inhibitors. We describe a case of an HIV-infected kidney transplant patient, who was noted to have a rising serum creatinine following initiation of dolutegravir. At first, an acute rejection episode was suspected, but this finding was later attributed to inhibition of creatinine secretion by dolutegravir. We suggest that an awareness of this potential effect of dolutegravir is important for providers who take care of HIV-positive kidney transplant recipients, in order to prevent potentially unnecessary testing.

Measures of Global Health Status on Dialysis Signal Early Rehospitalization Risk after Kidney Transplantation

BACKGROUND

Early rehospitalization (<30 days) after discharge from kidney transplantation (KT) is associated with poor outcomes. We explored summary metrics of pre-transplant health status that may improve the identification of KT recipients at risk for early rehospitalization and mortality after transplant.

MATERIALS AND METHODS

We performed a retrospective cohort study of 8,870 adult (≥ 18 years) patients on hemodialysis who received KT between 2000 and 2010 at United States transplant centers. We linked Medicare data to United Network for Organ Sharing data and data from a national dialysis provider to examine pre-KT (1) Elixhauser Comorbidity Index, (2) physical function (PF) measured by the Short Form 36 Health Survey, and (3) the number of hospitalizations during the 12 months before KT as potential predictors of early rehospitalization after KT. We also explored whether these metrics are confounders of the known association between early rehospitalization and post-transplant mortality.

RESULTS

The median age was 52 years (interquartile range [IQR] 41, 60) and 63% were male. 29% were rehospitalized in <30 days, and 20% died during a median follow-up time of five years (IQR 3.6-6.5). In a multivariable logistic model, kidney recipients with more pre-KT Elixhauser comorbidities (adjusted odds ratio [aOR] 1.09 per comorbidity, 95% Confidence Interval [CI] 1.07-1.11), the poorest pre-KT PF (aOR 1.24, 95% CI 1.08-1.43), or >1 pre-KT hospitalizations (aOR 1.32, 95% CI 1.17-1.49) were more likely to be rehospitalized. All three health status metrics and early rehospitalization were independently associated with post-KT mortality in a multivariable Cox model (adjusted hazard ratio for rehospitalization: 1.41, 95% CI 1.28-1.56).

CONCLUSIONS

Pre-transplant metrics of health status, measured by dialysis providers or administrative data, are independently associated with early rehospitalization and mortality risk after KT. Transplant providers may consider utilizing metrics of pre-KT global health status as early signals of vulnerability when transitioning care after KT.

Sarcopenia and mortality among a population-based sample of community-dwelling older adults

BACKGROUND

Sarcopenia is a risk-factor for all-cause mortality among older adults, but it is unknown if sarcopenia predisposes older adults to specific causes of death. Further, it is unknown if the prognostic role of sarcopenia differs between males and females, and obese and non-obese individuals.

METHODS

A population-based cohort study among 4425 older adults from the Third National Health and Nutrition Survey (1988-1994). Muscle mass was quantified using bioimpedance analysis, and muscle function was quantified using gait speed. Multivariable-adjusted Cox regression analysis examined the relationship between sarcopenia and mortality outcomes.

RESULTS

The mean age of study participants was 70.1 years. The prevalence of sarcopenia was 36.5%. Sarcopenia associated with an increased risk of all-cause mortality [hazard ratio (HR): 1.29 (95% confidence interval (95% CI): 1.13-1.47); P < 0.001] among males and females. Sarcopenia associated with an increased risk of cardiovascular-specific mortality among females [HR: 1.61 (95% CI: 1.22-2.12); P = 0.001], but not among males [HR: 1.07 (95% CI: 0.81-1.40; P = .643); P interaction = 0.079]. Sarcopenia was not associated with cancer-specific mortality among males and females [HR: 1.07 (95% CI: 0.78-1.89); P = 0.672]. Sarcopenia associated with an increased risk of mortality from other causes (i.e. non-cardiovascular and non-cancer) among males and females [HR: 1.32 (95% CI: 1.07-1.62); P = 0.008]. Obesity, defined using body mass index (P interaction = 0.817) or waist circumference (P interaction = 0.219) did not modify the relationship between sarcopenia and all-cause mortality.

CONCLUSIONS

Sarcopenia is a prevalent syndrome that is associated with premature mortality among community-dwelling older adults. The prognostic value of sarcopenia may vary by cause-specific mortality and differ between males and females.

Patient-reported versus objectively-measured physical function and mortality risk among cancer survivors

OBJECTIVE

This study aimed to characterize the relationship of patient-reported functional limitations, gait speed, and mortality risk among cancer survivors.

MATERIALS AND METHODS

This study included cancer survivors from the Third National Health and Nutrition Survey. Patient-reported functional limitations were quantified by asking participants to assess their ability to complete five tasks: (1) walking 1/4 mi, (2) walking up 10 steps, (3) stooping, crouching, or kneeling, (4) lifting or carrying an object of 10 lb, and (5) standing up from an armless chair. Gait speed was quantified using a 2.4-meter walk. Vital status was obtained through the United States National Center for Health Statistics.

RESULTS

The study sample included 428 cancer survivors who averaged 72.1 years of age. The average number of patient-reported functional limitations was 1.8 (out of 5) and 66% of participants reported ≥1 functional limitation. Patient-reported functional limitations and gait speed were related, such that each functional limitation associated with a -0.08m/s slower gait speed (95% confidence interval: -0.10 to -0.06; P<0.001). During a median follow-up of 11years, 329 (77%) participants died. In multivariable-adjusted analysis, patient-reported functional limitations and survival were related, such that each additional reported functional limitation was associated with a 19% increase in the risk of death (95% confidence interval: 9% to 29%; P<0.001).

CONCLUSION

Patient-reported functional limitations are prevalent among cancer survivors, and associate with slower gait speeds and shorter survival. These data may provide increased insight on long-term prognosis and inform clinical decision-making by identifying subgroups of cancer survivors who may benefit from rehabilitative intervention.

Altitude and regional gradients in chronic kidney disease prevalence in Costa Rica: Data from the Costa Rican Longevity and Healthy Aging Study

OBJECTIVES

Recent studies in Central America indicate that mortality attributable to chronic kidney disease (CKD) is rising rapidly. We sought to determine the prevalence and regional variation of CKD and the relationship of biologic and socio-economic factors to CKD risk in the older-adult population of Costa Rica.

METHODS

We used data from the Costa Rican Longevity and Health Aging Study (CRELES). The cohort was comprised of 2657 adults born before 1946 in Costa Rica, chosen through a sampling algorithm to represent the national population of Costa Ricans >60 years of age. Participants answered questionnaire data and completed laboratory testing. The primary outcome of this study was CKD, defined as an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2 .

RESULTS

The estimated prevalence of CKD for older Costa Ricans was 20% (95% CI 18.5-21.9%). In multivariable logistic regression, older age (adjusted odds ratio [aOR] 1.08 per year, 95% CI 1.07-1.10, P < 0.001) was independently associated with CKD. For every 200 m above sea level of residence, subjects' odds of CKD increased 26% (aOR 1.26 95% CI 1.15-1.38, P < 0.001). There was large regional variation in adjusted CKD prevalence, highest in Limon (40%, 95% CI 30-50%) and Guanacaste (36%, 95% CI 26-46%) provinces. Regional and altitude effects remained robust after adjustment for socio-economic status.

CONCLUSIONS

We observed large regional and altitude-related variations in CKD prevalence in Costa Rica, not explained by the distribution of traditional CKD risk factors. More studies are needed to explore the potential association of geographic and environmental exposures with the risk of CKD.

The Prognostic Importance of Frailty in Cancer Survivors

OBJECTIVES

To quantify the prognostic importance of prefrailty and frailty in a population-based sample of cancer survivors.

DESIGN

The Third National Health and Nutrition Examination Survey mortality-linked prospective cohort study.

SETTING

Eighty-nine survey locations across the United States.

PARTICIPANTS

Population-based sample of older adults (average age 72.2) with a self-reported diagnosis of non-skin-related cancer (N = 416).

MEASUREMENTS

The primary outcome was all-cause mortality. Frailty components included low weight for height, slow walking, weakness, exhaustion, and low physical activity. Participants with none of the five criteria were classified as nonfrail, those with one or two as prefrail, and those with three or more as frail.

RESULTS

The prevalence of prefrailty was 37.3% and of frailty was 9.1%. During a median follow-up of 11.2 years, 319 (76.7%) participants died. Median survival was 13.9 years for participants classified as nonfrail, 9.5 years for those classified as prefrail, and 2.5 years for those classified as frail. Cancer survivors classified as prefrail (hazard ratio (HR) = 1.84, 95% confidence interval (CI) = 1.28-2.65, P = .001) or frail (HR = 2.79, 95% CI = 1.34-5.81, P = .006) had a higher risk of premature mortality than those classified as nonfrail.

CONCLUSION

Prefrailty and frailty are prevalent clinical syndromes that may confer greater risk of premature mortality in older adult cancer survivors. Identifying frail cancer survivors and targeting interventions for them may be a strategy to improve survival after cancer.