Faculty Bibliography

BACKGROUND & AIMS: We sought to estimate the risk of perioperative mortality or acute liver failure for live liver donors in the United States and avoid selection or ascertainment biases and sample size limitations. METHODS: We followed up 4111 live liver donors in the United States between April 1994 and March 2011 for a mean of 7.6 years; deaths were determined from the Social Security Death Master File. Survival data were compared with those from live kidney donors and healthy participants of the National Health and Nutrition Examination Survey (NHANES) III. RESULTS: Seven donors had early deaths (1.7 per 1000; 95% confidence interval [CI], 0.7-3.5); risk of death did not vary with age of the liver recipient (1.7 per 1000 for adults vs 1.6 per 1000 for pediatric recipients; P = .9) or portion of liver donated (2.0 per 1000 for left lateral segment, 2.8 per 1000 for left lobe, and 1.5 per 1000 for right lobe; P = .8). There were 11 catastrophic events (early deaths or acute liver failures; 2.9 per 1000; 95% CI, 1.5-5.1); similarly, risk did not vary with recipient age (3.1 per 1000 adult vs 1.6 per 1000 pediatric; P = .4) or portion of liver donated (2.0 per 1000 for left lateral segment, 2.8 per 1000 for left lobe, and 3.3 per 1000 for right lobe; P = .9). Long-term mortality of live liver donors was comparable to that of live kidney donors and NHANES participants (1.2%, 1.2%, and 1.4% at 11 years, respectively; P = .9). CONCLUSIONS: The risk of early death among live liver donors in the United States is 1.7 per 1000 donors. Mortality of live liver donors does not differ from that of healthy, matched individuals over a mean of 7.6 years.

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.

A causal link has been proposed between presumed consent (PC) and increased donation; we hypothesized that too much heterogeneity exists in transplantation systems to support this inference. We explored variations in PC implementation and other potential factors affecting donation rates. In-depth interviews were performed with senior transplant physicians from 13 European PC countries. Donation was always discussed with family and would not proceed against objections. Country-specific, nonconsent factors were identified that could explain differences in donation rates. Because the process of donation in PC countries does not differ dramatically from the process in non-PC countries, it seems unlikely that PC alone increases donation rates.

Model for End-stage Liver Disease (MELD)-based allocation of deceased donor livers allows exceptions for patients whose score may not reflect their true mortality risk. We hypothesized that organ procurement organizations (OPOs) may differ in exception practices, use of exceptions may be increasing over time, and exception patients may be advantaged relative to other patients. We analyzed longitudinal MELD score, exception and outcome in 88 981 adult liver candidates as reported to the United Network for Organ Sharing from 2002 to 2010. Proportion of patients receiving an HCC exception was 0-21.4% at the OPO-level and 11.9-18.8% at the region level; proportion receiving an exception for other conditions was 0.0%-13.1% (OPO-level) and 3.7-9.5 (region-level). Hepatocellular carcinoma (HCC) exceptions rose over time (10.5% in 2002 vs. 15.5% in 2008, HR = 1.09 per year, p<0.001) as did other exceptions (7.0% in 2002 vs. 13.5% in 2008, HR = 1.11, p<0.001). In the most recent era of HCC point assignment (since April 2005), both HCC and other exceptions were associated with decreased risk of waitlist mortality compared to nonexception patients with equivalent listing priority (multinomial logistic regression odds ratio [OR] = 0.47 for HCC, OR = 0.43 for other, p<0.001) and increased odds of transplant (OR = 1.65 for HCC, OR = 1.33 for other, p<0.001). Policy advantages patients with MELD exceptions; differing rates of exceptions by OPO may create, or reflect, geographic inequity.

Liver transplantation has evolved over the past four decades into the most effective method to treat end-stage liver failure and one of the most expensive medical technologies available. Accurate understanding of the financial implication of recipient severity of illness is crucial to assessing the economic impact of allocation policies. A novel database of linked clinical data from the Organ Procurement and Transplantation Network with cost accounting data from the University HealthSystem Consortium was used to analyze liver transplant costs for 15,813 liver transplants. This data was then utilized to consider the economic impact of alternative allocation systems designed to increase sharing of liver allografts using simulation results. Transplant costs were strongly associated with recipient severity of illness as assessed by the MELD score (p < 0.0001); however, this relationship was not linear. Simulation analysis of the reallocation of livers from low MELD patients to high MELD using a two-tiered regional sharing approach (MELD 15/25) resulted in 88 fewer deaths annually at estimated cost of $17,056 per quality-adjusted life-year saved. The results suggest that broader sharing of liver allografts offers a cost-effective strategy to reduce the mortality from end stage liver disease.