Faculty Bibliography

Severe geographic disparities exist in liver transplantation; for patients with comparable disease severity, 90-day transplant rates range from 18% to 86% and death rates range from 14% to 82% across donation service areas (DSAs). Broader sharing has been proposed to resolve geographic inequity; however, we hypothesized that the efficacy of broader sharing depends on the geographic partitions used. To determine the potential impact of redistricting on geographic disparity in disease severity at transplantation, we combined existing DSAs into novel regions using mathematical redistricting optimization. Optimized maps and current maps were evaluated using the Liver Simulated Allocation Model. Primary analysis was based on 6700 deceased donors, 28 063 liver transplant candidates, and 242 727 Model of End-Stage Liver Disease (MELD) changes in 2010. Fully regional sharing within the current regional map would paradoxically worsen geographic disparity (variance in MELD at transplantation increases from 11.2 to 13.5, p = 0.021), although it would decrease waitlist deaths (from 1368 to 1329, p = 0.002). In contrast, regional sharing within an optimized map would significantly reduce geographic disparity (to 7.0, p = 0.002) while achieving a larger decrease in waitlist deaths (to 1307, p = 0.002). Redistricting optimization, but not broader sharing alone, would reduce geographic disparity in allocation of livers for transplant across the United States.

Over 10% of deceased donors in 2011 met PHS/CDC criteria for infectious risk donor (IRD), and discard rates are significantly higher for kidneys from these donors. We hypothesized that patient phenotypes exist for whom the survival benefit outweighs the infectious risk associated with IRDs. A patient-oriented Markov decision process model was developed and validated, based on SRTR data and meta-analyses of window period risks among persons with IRD behaviors. The Markov model allows patients to see, for their phenotype, their estimated survival after accepting versus declining an IRD offer, graphed over a 5-year horizon. Estimated 5-year survival differences associated with accepting IRDs ranged from -6.4% to +67.3% for a variety of patient phenotypes. Factors most predictive of the survival difference with IRD transplantation were age, PRA, previous transplant, and the expected time until the next non-IRD deceased donor offer. This study suggests that survival benefit derived from IRD kidneys varies widely by patient phenotype. Furthermore, within the inherent limitations of model-based prediction, this study demonstrates that it is possible to identify those predicted to benefit from IRD kidneys, and illustrates how estimated survival curves based on a clinical decision can be presented to better inform patient and provider decision-making.

With many multicenter consortia and a United Network for Organ Sharing program, participation in kidney paired donation (KPD) has become mainstream in the United States and should be feasible for any center that performs live donor kidney transplantation (LDKT). Lack of participation in KPD may significantly disadvantage patients with incompatible donors. To explore utilization of this modality, we analyzed adjusted center-specific KPD rates based on casemix of adult LDKT-eligible patients at 207 centers between 2006 and 2011 using SRTR data. From 2006 to 2008, KPD transplants became more evenly distributed across centers, but from 2008 to 2011 the distribution remained unchanged (Gini coefficient = 0.91 for 2006, 0.76 for 2008 and 0.77 for 2011), showing an unfortunate stall in dissemination. At the 10% of centers with the highest KPD rates, 9.9-38.5% of LDKTs occurred through KPD during 2009-2011; if all centers adopted KPD at rates observed in the very high-KPD centers, the number of KPD transplants per year would increase by a factor of 3.2 (from 494 to 1593). Broader implementation of KPD across a wide number of centers is crucial to properly serve transplant candidates with healthy but incompatible live donors.

Organ shortage has led to increased utilization of higher risk liver allografts. In kidneys, aggressive center-level use of one type of higher risk graft clustered with aggressive use of other types. In this study, we explored center-level behavior in liver utilization. We aggregated national liver transplant recipient data between 2005 and 2009 to the center-level, assigning each center an aggressiveness score based on relative utilization of higher risk livers. Aggressive centers had significantly more patients reaching high MELDs (RR 2.19, 2.33 and 2.28 for number of patients reaching MELD>20, MELD>25 and MELD>30, p<0.001), a higher organ shortage ratio (RR 1.51, 1.60 and 1.51 for number of patients reaching MELD>20, MELD>25 and MELD>30 divided by number of organs recovered at the OPO, p<0.04), and were clustered within various geographic regions, particularly regions 2, 3 and 9. Median MELD at transplant was similar between aggressive and nonaggressive centers, but average annual transplant volume was significantly higher at aggressive centers (RR 2.27, 95% CI 1.47-3.51, p<0.001). In cluster analysis, there were no obvious phenotypic patterns among centers with intermediate levels of aggressiveness. In conclusion, highwaitlist disease severity, geographic differences in organ availability, and transplant volume are the main factors associated with the aggressive utilization of higher risk livers.

In November 2003, OPTN policy was amended to allow kidney transplant candidates to accrue waiting time while registered as status 7, or inactive. We evaluated trends in inactive listings and the association of inactive status with transplantation and survival, studying 262,824 adult first-time KT candidates listed between 2000 and 2011. The proportion of waitlist candidates initially listed as inactive increased from 2.3% prepolicy change to 31.4% in 2011. Candidates initially listed as inactive were older, more often female, African American, and with higher body mass index. Postpolicy change, conversion from initially inactive to active status generally occurred early if at all: at 1 year after listing, 52.7% of initially inactive candidates had been activated; at 3 years, only 66.3% had been activated. Inactive status was associated with a substantially higher waitlist mortality (aHR 2.21, 95%CI:2.15-2.28, p<0.001) and lower rates of eventual transplantation (aRR 0.68, 95%CI:0.67-0.70, p<0.001). In summary, waitlist practice has changed significantly since November 2003, with a sharp increase in the number of inactive candidates. Using the full waitlist to estimate organ shortage or as a comparison group in transplant outcome studies is less appropriate in the current era.

BACKGROUND:Initial therapy for early hepatocellular carcinoma (HCC) with well-compensated cirrhosis is controversial. While we previously reported on the effect of clinical factors and surgeon specialty on choice of therapy for early HCC, other nonclinical factors also may impact decision-making. METHODS:Surgeons who treat HCC were invited to complete a web-based survey that included ten case scenarios. Choice of therapy-liver transplantation (LT), liver resection (LR), or radiofrequency ablation (RFA)-was analyzed using regression models. RESULTS:There were 336 responses for analysis. Most respondents were in academic centers (86 %) that offered LT (71 %). The median number of patients annually evaluated for HCC was 30. Both practice type and HCC case volume were associated with choice of therapy, but these associations were not independent of surgeon specialty. LT surgeons who did not also perform RFA were less likely than those LT surgeons who did offer RFA to choose RFA over LT (relative risk ratios (RRR) 0.38, P < 0.001). Non-LT surgeons were more likely than LT surgeons who also offered RFA to choose RFA over LT (RRR 2.24, P < 0.001). Surgeons who worked at hospitals where LT was performed were much more likely to choose LT over LR and RFA even if they did not personally perform LT (RRR 1.27 and RRR 3.33, P < 0.001). CONCLUSIONS:Surgeon- and institution-related factors impact choice of therapy for early HCC even after adjustment for differences in clinical presentation. These data suggest that choice of therapy for patients with early HCC varies across providers independent of case selection.

BACKGROUND:Disparity in access to liver transplantation (LT) in the United States persists despite directives from the federal government to reduce geographic variation. We assessed the impact of socioeconomic status (SES) and traveling to alternative donation service areas (DSAs) on patient survival. METHODS:A prospective cohort study integrating transplant registry and U.S. Census data was analyzed using multivariate linear Cox proportional hazards models. A separate matched-pairs analysis was used to assess the benefit of traveling on patient survival and transplantation rate. RESULTS:High SES is associated with increased access to LT (adjusted hazard ratio [aHR], 1.05; 95% confidence interval [95% CI], 1.01-1.08) and reduced mortality after waitlisting (aHR [95% CI], 0.88 [0.85-0.93]). Increased access is mediated, in part, through inter-DSA travel. Travel was associated with high SES, white race, blood group O, private insurance, and residence in regions 1, 5, and 11. Transplant candidates in the highest SES quartile were approximately 70% more likely to travel (aHR [95% CI], 1.67 [1.43-1.97]) than those in the lowest SES quartile. Compared with matched control patients, travelers were 74% more likely to be transplanted (aHR [95% CI], 1.74 [1.56-1.94]) and 20% less likely to die after listing (aHR [95% CI], 0.79 [0.69-0.92]). CONCLUSION/CONCLUSIONS:High SES and inter-DSA travel are strongly associated with increased LT access and reduced mortality. Travelers are more likely to be sociodemographically advantaged and privately insured and to live in regions with reduced access to deceased-donor organs.

OBJECTIVE:To determine the burden of maternal morbidity in early pregnancy in rural northern Bangladesh. METHODS:A cross-sectional analysis was performed on baseline morbidity data from 42 896 pregnant women enrolled in a vitamin A supplementation trial. One-week histories for 31 defined symptoms were collected at 5-12 weeks of gestation. Ten illnesses were defined, compatible with ICD-10 diagnoses and WHO definitions. Prevalence, duration, and treatment-seeking behaviors were determined for each symptom and illness. Risk of wasting malnutrition was compared between symptomatic and asymptomatic women. RESULTS:In total, 93.1% of women reported at least 1 symptom. The most frequent symptoms were poor appetite (53.3%), vaginal discharge (48.7%), and nausea (48.1%), each of which lasted 22-27 days. The most prevalent illnesses were anemia (36.4%), morning sickness (17.2%), excessive vomiting (7.0%), and reproductive tract infections (6.7%). Symptoms that prompted treatment seeking included jaundice, high-grade fever, and swelling of hands and face. Odds ratios for malnutrition were higher among women with symptoms of anemia (1.30; 95% confidence interval [CI], 1.24-1.36), vaginal discharge (1.37; 95% CI, 1.31-1.43), and high-grade fever (1.23; 95% CI, 1.10-1.37) than among those without symptoms. CONCLUSION/CONCLUSIONS:Women in rural Bangladesh report substantial morbidity in the first trimester.

OBJECTIVES: To develop a prediction model for kidney transplantation (KT) outcomes specific to older adults with end-stage renal disease (ESRD) and to use this model to estimate the number of excellent older KT candidates who lack access to KT. DESIGN: Secondary analysis of data collected by the United Network for Organ Sharing and U.S. Renal Disease System. SETTING: Retrospective analysis of national registry data. PARTICIPANTS: Model development: Medicare-primary older recipients (aged >/= 65) of a first KT between 1999 and 2006 (N = 6,988). Model application: incident Medicare-primary older adults with ESRD between 1999 and 2006 without an absolute or relative contraindication to transplantation (N = 128,850). MEASUREMENTS: Comorbid conditions were extracted from U.S. Renal Disease System Form 2728 data and Medicare claims. RESULTS: The prediction model used 19 variables to estimate post-KT outcome and showed good calibration (Hosmer-Lemeshow P = .44) and better prediction than previous population-average models (P < .001). Application of the model to the population with incident ESRD identified 11,756 excellent older transplant candidates (defined as >87% predicted 3-year post-KT survival, corresponding to the top 20% of transplanted older adults used in model development), of whom 76.3% (n = 8,966) lacked access. It was estimated that 11% of these candidates would have identified a suitable live donor had they been referred for KT. CONCLUSION: A risk-prediction model specific to older adults can identify excellent KT candidates. Appropriate referral could result in significantly greater rates of KT in older adults.