Regional Social Vulnerability is Associated With Geographic Disparity in Waitlist Outcomes for Patients With Non-Hepatocellular Carcinoma Model for End-stage Liver Disease Exceptions in the United States.

OBJECTIVE: This study was undertaken to evaluate the role of regional social vulnerability in geographic disparity for patients listed for liver transplantation with non-hepatocellular carcinoma (HCC) model for end-stage liver disease (MELD) exceptions. SUMMARY AND BACKGROUND: Prior work has demonstrated regional variability in the appropriateness of MELD exceptions for diagnoses other than HCC. METHODS: Adults listed at a single center for first-time liver-only transplantation without HCC after June 18, 2013 in the Scientific Registry of Transplant Recipients database as of March 2021 were examined. Candidates were mapped to hospital referral regions (HRRs). Adjusted likelihood of mortality and liver transplantation were modeled. Advantaged HRRs were defined as those where exception patients were more likely to be transplanted, yet no more likely to die in adjusted analysis. The Centers for Disease Control's Social Vulnerability Index (SVI) was used as the measure for community health. Higher SVIs indicate poorer community health. RESULTS: There were 49,494 candidates in the cohort, of whom 4337 (8.8%) had MELD exceptions. Among continental US HRRs, 27.3% (n = 78) were identified as advantaged. The mean SVI of advantaged HRRs was 0.42 versus 0.53 in nonadvantaged HRRs ( P = 0.002), indicating better community health in these areas. Only 25.3% of advantaged HRRs were in spatial clusters of high SVI versus 40.7% of nonadvantaged HRRs, whereas 44.6% of advantaged HRRs were in spatial clusters of low SVI versus 38.0% of nonadvantaged HRRs ( P = 0.037). CONCLUSIONS: An advantage for non-HCC MELD exception patients is associated with lower social vulnerability on a population level. These findings suggest assigning similar waitlist priority to all non-HCC exception candidates without considering geographic differences in social determinants of health may actually exacerbate rather than ameliorate disparity.

Non-invasive evaluation of hepatic macrosteatosis in deceased donors.

INTRODUCTION: Liver allocation changes have led to increased travel and expenditures, highlighting the need to efficiently identify marginal livers suitable for transplant. We evaluated the validity of existing non-invasive liver quality tests and a novel machine learning-based model at predicting deceased donor macrosteatosis >30%. METHODS: We compared previously-validated non-invasive tests and a novel machine learning-based model to biopsies in predicting macrosteatosis >30%. We also tested them in populations enriched for macrosteatosis. RESULTS: The Hepatic Steatosis Index area-under-the-curve (AUC) was 0.56. At the threshold identified by Youden's J statistic, sensitivity, specificity, positive, and negative predictive values were 49.6%, 58.9%, 14.0%, and 89.7%. Other tests demonstrated comparable results. Machine learning produced the highest AUC (0.71). Even in populations enriched for macrosteatosis, no test was sufficiently predictive. CONCLUSION: Commonly used clinical scoring systems and a novel machine learning-based model were not clinically useful, highlighting the importance of pre-procurement biopsies to facilitate allocation.

County-level Differences in Liver-related Mortality, Waitlisting, and Liver Transplantation in the United States.

BACKGROUND: Much of our understanding regarding geographic issues in transplantation is based on statistical techniques that do not formally account for geography and is based on obsolete boundaries such as donation service area. METHODS: We applied spatial epidemiological techniques to analyze liver-related mortality and access to liver transplant services at the county level using data from the Centers for Disease Control and Prevention and Scientific Registry of Transplant Recipients from 2010 to 2018. RESULTS: There was a significant negative spatial correlation between transplant rates and liver-related mortality at the county level (Moran's I, -0.319; P = 0.001). Significant clusters were identified with high transplant rates and low liver-related mortality. Counties in geographic clusters with high ratios of liver transplants to liver-related deaths had more liver transplant centers within 150 nautical miles (6.7 versus 3.6 centers; P < 0.001) compared with all other counties, as did counties in geographic clusters with high ratios of waitlist additions to liver-related deaths (8.5 versus 2.5 centers; P < 0.001). The spatial correlation between waitlist mortality and overall liver-related mortality was positive (Moran's I, 0.060; P = 0.001) but weaker. Several areas with high waitlist mortality had some of the lowest overall liver-related mortality in the country. CONCLUSIONS: These data suggest that high waitlist mortality and allocation model for end-stage liver disease do not necessarily correlate with decreased access to transplant, whereas local transplant center density is associated with better access to waitlisting and transplant.

Lost potential and missed opportunities for DCD liver transplantation in the United States.

BACKGROUND: Donation after cardiac death(DCD) has been proposed as an avenue to expand the liver donor pool. METHODS: We examined factors associated with nonrecovery of DCD livers using UNOS data from 2015 to 2019. RESULTS: There 265 non-recovered potential(NRP) DCD livers. Blood type AB (7.8% vs. 1.1%) and B (16.9% vs. 9.8%) were more frequent in the NRP versus actual donors (p < 0.001). The median driving time between donor hospital and transplant center was similar for NRP and actual donors (30.1 min vs. 30.0 min; p = 0.689), as was the percentage located within a transplant hospital (20.8% vs. 20.9%; p = 0.984).The donation service area(DSA) of a donor hospital explained 27.9% (p = 0.001) of the variability in whether a DCD liver was recovered. CONCLUSION: A number of potentially high quality DCD donor livers go unrecovered each year, which may be partially explained by donor blood type and variation in regional and DSA level practice patterns.

Donor-reported barriers to living kidney donor follow-up.

BACKGROUND: Despite regulations mandating follow-up laboratory testing for living kidney donors, less than half of transplant centers are in compliance. We sought to understand barriers to follow-up testing from the donors' perspective. METHODS: We surveyed our center's living kidney donors. Binary logistic regression was used to assess factors associated with follow-up testing completion. RESULTS: Of 185 living kidney donors, 110 (59.4%) participated. Among them, 82 (74.5%) completed 6-month laboratory testing, 76 (69.1%) completed 12-month testing, 68 (61.8%) completed both, and 21 (19.0%) completed neither. Six-month testing completion was strongly associated with 12-month testing completion (OR 9.74, 95%CI: 2.23-42.50; p = .002). Those who disagreed with the statements, "Getting labs checked wasn't a priority for me," (OR for completing 6-month testing: 15.05, 95%CI: 3.70-61.18; p < .001; OR for completing 12-month testing: 5.85, 95%CI: 1.94-17.63; p = .002); and, "I forgot to get labs drawn [until I was reminded]" (OR for completing 6-month testing: 6.93, 95%CI: 1.59-30.08; p = .01; OR for completing 12-month testing: 6.55, 95%CI: 1.98-21.63; p = .002) were more likely to complete testing. CONCLUSIONS: To our knowledge, this is the only study providing perspective on donor insights regarding the need for follow-up testing post donation. Interventions to influence living donor attitudes toward follow-up testing may improve follow-up.

Hepatic macrosteatosis in the US pediatric deceased liver donor population.

INTRODUCTION: The pediatric obesity epidemic is associated with early development of hepatic macrosteatosis, a hallmark of non-alcoholic fatty LI disease, which is thought to be more rapidly progressive in children than adults. Macrosteatosis in adult allografts is associated with allograft loss, but this has not been examined in pediatric donors. METHODS: We studied all pediatric potential whole LI donors (2005-2018) who had a LI biopsy in the SRTR (n = 862) and whose LI was transplanted (n = 862). Macrosteatosis was abstracted from biopsy reports and compared to values in the SRTR standard analytic file. Recipients of macrosteatotic pediatric allografts were matched 1:1 to recipients of non-macrosteatotic pediatric allografts by propensity score matching on donor/recipient variables. All-cause allograft loss was estimated via Kaplan-Meier analysis and Cox proportional hazards model. RESULTS: From 2005 to 2018, the proportion of pediatric donors (age ≥2 years) with obesity increased (14.8% to 21.7%; p < .001), as did the proportion of pediatric deceased whole LI-only donor allografts with macrosteatosis (n = 10 648; 1.8% to 3.9%; p < .001). The median degree of macrosteatosis among macrosteatotic donors was 10% (IQR 5-30). There were no significant differences in all-cause allograft loss between recipients of pediatric LI allografts with and without macrosteatosis at 90 days (p = .11) or 1 year (p = .14) post-transplant in Kaplan-Meier analysis or a Cox proportional hazards model (p > .05). CONCLUSION: Obese pediatric LI donors have increased over time and were more likely to have hepatic macrosteatosis; however, pediatric macrosteatosis did not appear to adversely affect recipient outcomes.

Patient survival following third time liver transplant in the United States in the MELD era.

BACKGROUND: Third time liver transplantation is a technically demanding exercise with variable outcomes in single center series. There has been no national level description of survival following third time liver transplant in the US in the MELD era. METHODS: Third time liver transplants between March 1, 2002 and January 1, 2018 in the UNOS dataset were analyzed. RESULTS: Patient survival among the 240 third time liver transplant recipients in the study at 1, 3, 5, and 10 years (71.8%, 62.4%, 59.1%, 49.5%) was significantly worse compared to primary liver transplant (90.6%, 83.9%, 78.8%, 67.6%; p < 0.001) and retransplant (77.1%, 70.3%, 65.6%, 54.9%; p = 0.014). Recipients who were under 43 years old, not on dialysis, without diabetes, and over 1 month out from their second transplant had acceptable survival at 1, 3, 5, and 10 years (88.5%, 78.4%, 73.6%, 69.7%). CONCLUSIONS: While redo-redo transplant remains a challenging endeavor, appropriate patient selection can yield acceptable results.

Gender disparities in transplantation.

PURPOSE OF REVIEW: Transplantation is the life-saving therapy for patients suffering from end-organ failure, and as such, equitable access to transplantation (ATT) is of paramount importance. Unfortunately, gender/sex-based disparities exist, and despite the transplant community's awareness of this injustice, gender/sex-based disparities have persisted for more than two decades. Importantly, no legislation or allocation policy has addressed inequity in ATT that women disproportionately face. In fact, introduction of the model for end-stage liver disease-based liver allocation system in 2002 widened the gender disparity gap and it continues to be in effect today. Moreover, women suffering from kidney disease are consistently less likely to be referred for transplant evaluation and subsequently less likely to achieve a kidney transplant, yet they comprise the majority of living kidney donors. RECENT FINDINGS: Acknowledging gender/sex-based disparities in ATT is the first step toward interventions aimed at mitigating this long-standing injustice in healthcare. SUMMARY: This article provides a background of end-stage liver and kidney disease in women, summarizes the existing literature describing the issue of gender disparity in ATT, and identifies potential areas of intervention and future investigation.

Obesity as an isolated contraindication to kidney transplantation in the end-stage renal disease population: A cohort study.

OBJECTIVE: The aim of this study was to characterize end-stage renal disease (ESRD) patients with obesity as their only contraindication to listing and to quantify wait-list and transplant access. METHODS: Using the US Renal Data System, a retrospective cohort study of incident dialysis cases (2012 to 2014) was performed. The primary outcomes were time to wait-listing and time to transplantation. RESULTS: Of 157,572 dialysis patients not already listed, 39,844 had BMI as their only demonstrable transplant contraindication. They tended to be younger, female, and Black. Compared with patients with BMI < 35, those with BMI 35 to 39.9, 40 to 44.9, and ≥45 were, respectively, 15% (adjusted hazard ratio [aHR] 0.85; 95% CI: 0.83-0.88; p < 0.001), 45% (aHR 0.55; 95% CI: 0.52-0.57; p < 0.001), and 71% (aHR 0.29; 95% CI: 0.27-0.31; p < 0.001) less likely to be wait-listed. Wait-listed patients with BMI 35 to 39.9 were 24% less likely to achieve transplant (aHR 0.76; 95% CI: 0.72-0.80; p < 0.0001), BMI 40 to 44.9 were 21% less likely (aHR 0.79; 95% CI: 0.72-0.86; p < 0.0001), and BMI ≥ 45 were 15% less likely (aHR 0.85; 95% CI: 0.75-0.95; p = 0.004) compared with patients with BMI < 35. CONCLUSIONS: Obesity was the sole contraindication to wait-listing for 40,000 dialysis patients. They were less likely to be wait-listed. For those who were, they had a lower likelihood of transplant. Aggressive weight-loss interventions may help this population achieve wait-listing and transplant.

National estimates of intestinal ostomy creation and reversal for trauma.

BACKGROUND: Intestinal ostomy creation after trauma is selectively indicated for destructive colon and rectal injuries. However, the nationwide rates of creation of ostomies for trauma and their reversal are not known. The objective of this study was to ascertain national estimates of trauma ostomy creation and reversal. METHODS: Weighted analysis of Healthcare Cost and Utilization Project Nationwide Readmissions Database 2014 to 2015 was performed. Adult trauma patients (≥16 years) with a hollow viscus injury were included. Patients with preexisting ostomies and permanent ostomies and those who died within 48 hours of admission were excluded. Rates of ostomy creation and same admission ostomy reversal were calculated. Rates of postdischarge ostomy reversal were calculated using the Kaplan-Meier estimator. Multivariable Cox proportional hazards model was used to determine factors associated with postdischarge trauma ostomy reversal. RESULTS: A total of 22,542 patients sustained a hollow viscus injury resulting in the creation of 2,145 ostomies (9.6%). The rate of same-admission ostomy reversal was 0.7% (n = 16). At 1, 3, 6, and 9 months, the cumulative stoma reversal rates were 0%, 7.6%, 31.0%, and 43.1%, respectively. The mean ± SD time from ostomy creation to reversal was 123 ± 6.7 days for those undergoing reversal. Injury Severity Score greater than 9 was significantly associated with ostomy nonreversal after discharge (hazard ratio, 0.41; 95% confidence interval, 0.26-0.66). Age, sex, insurance status, penetrating injury, Charlson Comorbidity Index, and hospital teaching status were not significantly associated with ostomy reversal. CONCLUSION: The nationwide rate of ostomy creation after trauma is nearly 10%. At 6 months postinjury, only one third of patients had undergone ostomy reversal. Future study is needed to understand patient and provider-level factors associated with trauma ostomy reversal. LEVEL OF EVIDENCE: Epidemiology, level III.