Sociodemographic Determinants of Waitlist and Posttransplant Survival Among End-Stage Liver Disease Patients.

While regional organ availability dominates discussions of distribution policy, community-level disparities remain poorly understood. We studied micro-geographic determinants of survival risk and their distribution across Donor Service Areas (DSAs). Scientific Registry of Transplant Recipients records for all adults waitlisted for liver transplantation 2002-2014 were reviewed. The primary exposure variables were county-level sociodemographic risk, as measured by the Community Health Score (CHS), a previously-validated composite index local health conditions, and distance to listing transplant center. Among 114 347 patients, the median CHS was 19.4 (range: 0-40). Compared the lowest risk counties (CHS 1-10), highest-risk counties (CHS 31-40) had more black (14.6% vs. 5.4%), publicly insured (44.9% vs. 33.0), and remote candidates (34.0% vs. 15.1% living >100 miles away). Higher-CHS candidates had greater waitlist mortality in Cox multivariable (HR 1.16 for CHS 31-40, 95% CI 1.11-1.21) and competing risks analysis (sHR 1.07, 95% CI 0.99-1.14). Post-transplant survival was similar across CHS quartiles. Living >25 miles from the transplant center conferred excess mortality risk (sHR 1.08, 95% CI 1.03-1.12). Proposed distribution changes would disproportionately impact DSAs with more high-CHS or distant candidates. Low-income, rural and minority patients experience excess mortality while awaiting transplant, and risk disproportionately worse outcomes with reduced organ availability under current proposals.

Belatacept Combined With Transient Calcineurin Inhibitor Therapy Prevents Rejection and Promotes Improved Long-Term Renal Allograft Function.

Belatacept, a T cell costimulation blocker, demonstrated superior renal function, lower cardiovascular risk, and improved graft and patient survival in renal transplant recipients. Despite the potential benefits, adoption of belatacept has been limited in part due to concerns regarding higher rates and grades of acute rejection in clinical trials. Since July 2011, we have utilized belatacept-based immunosuppression regimens in clinical practice. In this retrospective analysis of 745 patients undergoing renal transplantation at our center, we compared patients treated with belatacept (n = 535) with a historical cohort receiving a tacrolimus-based protocol (n = 205). Patient and graft survival were equivalent for all groups. An increased rate of acute rejection was observed in an initial cohort treated with a protocol similar to the low-intensity regimen from the BENEFIT trial versus the historical tacrolimus group (50.5% vs. 20.5%). The addition of a transient course of tacrolimus reduced rejection rates to acceptable levels (16%). Treatment with belatacept was associated with superior estimated GFR (belatacept 63.8 mL/min vs. tacrolimus 46.2 mL/min at 4 years, p < 0.0001). There were no differences in serious infections including rates of cytomegalovirus or BK viremia. We describe the development of a costimulatory blockade-based strategy that ultimately allows renal transplant recipients to achieve calcineurin inhibitor-free immunosuppression.

First-Year Waitlist Hospitalization and Subsequent Waitlist and Transplant Outcome.

Frailty is associated with inferior survival and increased resource requirements among kidney transplant candidates, but assessments are time-intensive and costly and require direct patient interaction. Waitlist hospitalization may be a proxy for patient fitness and could help those at risk of poor outcomes. We examined United States Renal Data System data from 51 111 adult end-stage renal disease patients with continuous Medicare coverage who were waitlisted for transplant from January 2000 to December 2011. Heavily admitted patients had higher subsequent resource requirements, increased waitlist mortality and decreased likelihood of transplant (death after listing: 1-7 days: hazard ratio [HR] 1.24, 95% confidence interval [CI] 1.20-1.28; 8-14 days: HR 1.49, 95% CI 1.42-1.56; ≥15 days: HR 2.07, 95% CI 1.99-2.15; vs. 0 days). Graft and recipient survival was inferior, with higher admissions, although survival benefit was preserved. A model including waitlist admissions alone performed better (C statistic 0.76, 95% CI 0.74-0.80) in predicting postlisting mortality than estimated posttransplant survival (C statistic 0.69, 95% CI 0.67-0.73). Although those with a heavy burden of admissions may still benefit from kidney transplant, less utility is derived from allografts placed in this population. Current kidney allocation policy, which is based in part on longevity matching, could be significantly improved by consideration of hospitalization records of transplant candidates.

One Size Does Not Fit All--Regional Variation in the Impact of the Share 35 Liver Allocation Policy.

Allocation policies for liver transplantation underwent significant changes in June 2013 with the introduction of Share 35. We aimed to examine the effect of Share 35 on regional variation in posttransplant outcomes. We examined two patient groups from the United Network for Organ Sharing dataset; a pre-Share 35 group composed of patients transplanted between June 17, 2012, and June 17, 2013 (n = 5523), and a post-Share group composed of patients transplanted between June 18, 2013, and June 18, 2014 (n = 5815). We used Kaplan-Meier and Cox multivariable analyses to compare survival. There were significant increases in allocation Model for End-stage Liver Disease (MELD) scores, laboratory MELD scores, and proportions of patients in the intensive care unit and on mechanical, ventilated, or organ-perfusion support at transplant post-Share 35. We also observed a significant increase in donor risk index in this group. We found no difference on a national level in survival between patients transplanted pre-Share 35 and post-Share 35 (p = 0.987). Regionally, however, posttransplantation survival was significantly worse in the post-Share 35 patients in regions 4 and 10 (p = 0.008 and p = 0.04), with no significant differences in the remaining regions. These results suggest that Share 35 has been associated with transplanting "sicker patients" with higher MELD scores, and although no difference in survival is observed on a national level, outcomes appear to be concerning in some regions.

Decreasing Estimated Glomerular Filtration Rate Is Associated With Increased Risk of Hospitalization After Kidney Transplantation.

INTRODUCTION: Following renal transplantation, decreased renal function is associated with increased risk of cardiovascular disease, graft loss and mortality. We investigated whether declining renal function was associated with hospitalization post-transplant. METHODS: Adult, first-time, kidney transplant recipients between 2004 and 2006 from the United Network for Organ Sharing database and hospitalizations one year after the 6-month post-transplant follow-up visit were examined. Generalized linear models explored the relationship between estimated glomerular filtration rate (eGFR) measured at 6 months and the number of hospitalizations in the following year. RESULTS: Of 15,778 kidney transplant recipients, 19.1% were admitted in the year after the 6-month follow-up visit. Among those hospitalized, the mean number of hospitalizations was 1.71 and increased with decreasing eGFR. In multivariable models, a decrease in eGFR was significantly associated with increased hospitalizations: for every 10 ml/min/1.73m2 decrease in eGFR, there was an 11% increase in hospitalization rate (p <0.001). Lower eGFR after the first 6 months following transplantation was associated with an increase in late hospitalizations among adult kidney transplant recipients. DISCUSSION: Identifying patients with declining eGFR and other risk factors may help prevent morbidity and mortality associated with hospitalization post-transplantation.

Kidney transplant access in the Southeast: view from the bottom.

The Southeastern region of the United States has the highest burden of end-stage renal disease (ESRD) but the lowest rates of kidney transplantation in the nation. There are many patient-, dialysis facility-, ESRD Network- and health system-level barriers that contribute to this regional disparity. Compared to the rest of the nation, the Southeast has a larger population of African-Americans and higher poverty, as well as more prevalent ESRD risk factors including hypertension, obesity and diabetes. Dialysis facilities--where ESRD patients receive the majority of their healthcare--play an important role in transplant access. Identifying characteristics of individual dialysis units with low rates of kidney transplantation, such as understaffing or for-profit status, can help identify targets for quality improvement initiatives. Geographic differences across the country can identify opportunities to increase funding for healthcare resources in proportion to patient and disease burden. Focusing interventions among dialysis facilities with the lowest transplant rates within the Southeast, such as provider and patient education, has the potential to increase referrals for kidney transplantation, leading to higher rates of kidney transplants in this region. Referral for transplantation should be measured on a national level to monitor disparities in early access to transplantation. Transplant centers have an obligation to assist underserved populations in ensuring equity in access to services. Policies that improve access to care for patients, such as the Affordable Care Act and Medicaid expansion, are particularly important for Southern states and may alleviate geographic disparities.

Dialysis facility and network factors associated with low kidney transplantation rates among United States dialysis facilities.

Variability in transplant rates between different dialysis units has been noted, yet little is known about facility-level factors associated with low standardized transplant ratios (STRs) across the United States End-stage Renal Disease (ESRD) Network regions. We analyzed Centers for Medicare & Medicaid Services Dialysis Facility Report data from 2007 to 2010 to examine facility-level factors associated with low STRs using multivariable mixed models. Among 4098 dialysis facilities treating 305 698 patients, there was wide variability in facility-level STRs across the 18 ESRD Networks. Four-year average STRs ranged from 0.69 (95% confidence interval [CI]: 0.64-0.73) in Network 6 (Southeastern Kidney Council) to 1.61 (95% CI: 1.47-1.76) in Network 1 (New England). Factors significantly associated with a lower STR (p < 0.0001) included for-profit status, facilities with higher percentage black patients, patients with no health insurance and patients with diabetes. A greater number of facility staff, more transplant centers per 10 000 ESRD patients and a higher percentage of patients who were employed or utilized peritoneal dialysis were associated with higher STRs. The lowest performing dialysis facilities were in the Southeastern United States. Understanding the modifiable facility-level factors associated with low transplant rates may inform interventions to improve access to transplantation.

Racial and ethnic differences in pediatric access to preemptive kidney transplantation in the United States.

Preemptive kidney transplantation is the optimal treatment for pediatric end stage renal disease patients to avoid increased morbidity and mortality associated with dialysis. It is unknown how race/ethnicity and poverty influence preemptive transplant access in pediatric. We examined the incidence of living donor or deceased donor preemptive transplantation among all black, white, and Hispanic children (<18 years) in the United States Renal Data System from 2000 to 2009. Adjusted risk ratios for preemptive transplant were calculated using multivariable-adjusted models and examined across health insurance and neighborhood poverty levels. Among 8,053 patients, 1117 (13.9%) received a preemptive transplant (66.9% from LD, 33.1% from DD). In multivariable analyses, there were significant racial/ethnic disparities in access to LD preemptive transplant where blacks were 66% (RR = 0.34; 95% CI: 0.28-0.43) and Hispanics 52% (RR = 0.48; 95% CI: 0.35-0.67) less likely to receive a LD preemptive transplant versus whites. Blacks were 22% less likely to receive a DD preemptive transplant versus whites (RR = 0.78, 95% CI: 0.57-1.05), although results were not statistically significant. Future efforts to promote equity in preemptive transplant should address the critical issues of improving access to pre-ESRD nephrology care and overcoming barriers in living donation, including obstacles partially driven by poverty.

Racial disparities in pediatric access to kidney transplantation: does socioeconomic status play a role?

Racial disparities persist in access to renal transplantation in the United States, but the degree to which patient and neighborhood socioeconomic status (SES) impacts racial disparities in deceased donor renal transplantation access has not been examined in the pediatric and adolescent end-stage renal disease (ESRD) population. We examined the interplay of race and SES in a population-based cohort of all incident pediatric ESRD patients <21 years from the United States Renal Data System from 2000 to 2008, followed through September 2009. Of 8452 patients included, 30.8% were black, 27.6% white-Hispanic, 44.3% female and 28.0% lived in poor neighborhoods. A total of 63.4% of the study population was placed on the waiting list and 32.5% received a deceased donor transplant. Racial disparities persisted in transplant even after adjustment for SES, where minorities were less likely to receive a transplant compared to whites, and this disparity was more pronounced among patients 18-20 years. Disparities in access to the waiting list were mitigated in Hispanic patients with private health insurance. Our study suggests that racial disparities in transplant access worsen as pediatric patients transition into young adulthood, and that SES does not explain all of the racial differences in access to kidney transplantation.

The role of race and poverty on steps to kidney transplantation in the Southeastern United States.

Racial disparities in access to renal transplantation exist, but the effects of race and socioeconomic status (SES) on early steps of renal transplantation have not been well explored. Adult patients referred for renal transplant evaluation at a single transplant center in the Southeastern United States from 2005 to 2007, followed through May 2010, were examined. Demographic and clinical data were obtained from patient's medical records and then linked with United States Renal Data System and American Community Survey Census data. Cox models examined the effect of race on referral, evaluation, waitlisting and organ receipt. Of 2291 patients, 64.9% were black, the mean age was 49.4 years and 33.6% lived in poor neighborhoods. Racial disparities were observed in access to referral, transplant evaluation, waitlisting and organ receipt. SES explained almost one-third of the lower rate of transplant among black versus white patients, but even after adjustment for demographic, clinical and SES factors, blacks had a 59% lower rate of transplant than whites (hazard ratio = 0.41; 95% confidence interval: 0.28-0.58). Results suggest that improving access to healthcare may reduce some, but not all, of the racial disparities in access to kidney transplantation.

Biological concentration of 3H.

In a three-year study, the possible biological concentration of 3H in rabbits was investigated. Tritiated water was used to grow alfalfa that was used exclusively as feed for the rabbits. Feed and water were kept at a constant 3H-to-1H ratio. The foundation group consisted of 18 female rabbits maintained on a 3H diet for 2 wk before mating. The subsequent generations were maintained with tritiated water and feed. At appropriate intervals, animals were sacrificed and selected tissues were analyzed for 3H. The specific activity of 3H in aqueous and organic fractions of tissues of all the animals remained essentially equal to that in the original water and feed. Results of this experiment indicate that under the steady-state equilibrium conditions of the experiment, no preferential concentration of 3H in animals occurred.

Results of a surveillance program for persons living around the Nevada Test Site--1971 to 1980.

A continuing program has been conducted since 1970 to determine levels of radioactive nuclides in adults and children from families residing in communities and ranches surrounding the Nevada Test Site. Twice each year these persons receive a whole-body count and physical examination; a urine sample from each is also submitted for radionuclide analyses. The only fission-product radionuclide routinely found in whole-body counting has been 137Cs at concentrations similar to those in persons living in other areas of the United States. The physical examinations reveal a generally healthy population, and urine samples have shown no remarkable radionuclide content.

Metabolic observations on Caucasian men and women aged 17 to 88 years.

Aerobic capacity (VO2 max) and body fat were measured indoors and VO2 was measured at about 36 to 42 degrees C in desert walks or runs in 69 adults aged 17 to 88 years. Eleven were athletic youths, and many of the older adults had participated in jogging programs. Body fat increased and VO2 max decreased with age, although there were notable exceptions. Rates of walking and running were planned to require about 40% of VO2 max. Midway in each walk VO2 (ml O2/horizontal m . kg) served as a measure of skill; skill was high in 10 of 11 youths who did many walks or runs. Each older adult did three walks; skill improved. In four groups with some persons aged 50 and older with body fat up to 40%, skill in their third walk matched that of youths. The least fit women and the least fit men did not attain that level of skill.