Faculty Bibliography

BACKGROUND AND OBJECTIVES: The profound organ shortage has resulted in longer waiting times and increased mortality for those awaiting kidney transplantation. Consequently, patients are turning to older living donors. It is unclear if an upper age limit for donation should exist, both in terms of recipient and donor outcomes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In the United States, 219 healthy adults aged >/=70 have donated kidneys at 80 of 279 transplant centers. Competing risks models with matched controls were used to study the independent association between older donor age and allograft survival, accounting for the competing risk of recipient mortality as well as other transplant factors. RESULTS: Among recipients of older live donor allografts, graft loss was significantly higher than matched 50-to 59-year-old live donor allografts (subhazard ratio [SHR] 1.62, 95% confidence interval [CI] 1.16 to 2.28, P = 0.005) but similar to matched nonextended criteria 50-to 59-year-old deceased donor allografts (SHR 1.19, 95% CI 0.87 to 1.63, P = 0.3). Mortality among living kidney donors aged >/=70 was no higher than healthy matched controls drawn from the NHANES-III cohort; in fact, mortality was lower, probably reflecting higher selectivity among older live donors than could be captured in National Health and Nutrition Examination Survey III (NHANES-III; HR 0.37, 95% CI 0.21 to 0.65, P < 0.001). CONCLUSIONS: These findings support living donation among older adults but highlight the advantages of finding a younger donor, particularly for younger recipients.

BACKGROUND: African Americans have lower rates of obtaining a deceased donor kidney transplant (DDKT) compared with their white counterparts. One proposed mechanism is differential HLA distributions between African Americans and whites. In May 2003, the United Network for Organ Sharing/Organ Procurement and Transplantation Network changed kidney allocation policy to eliminate priority based on HLA-B matching in an effort to address this disparity. The objective of this study was to quantify the effect of the change in policy regarding priority points for HLA-B matching. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: A cohort of 178,902 patients registered for a DDKT between January 2000 and August 2009. FACTORS: African Americans versus whites before and after the policy change. Cox models were adjusted for age, sex, diabetes, dialysis type, insurance status, education, panel-reactive antibody level, and blood type. OUTCOMES: Adjusted relative rates (aRRs) of deceased donor kidney transplant for African Americans compared with whites. MEASUREMENTS: Time from initial active wait listing to DDKT, censored for living donor kidney transplant and death. RESULTS: Before the policy change, African Americans had 37% lower rates of DDKT (aRR, 0.63; 95% CI, 0.60-0.65; P < 0.001). After the policy change, African Americans had 23% lower rates of DDKT (aRR, 0.77; 95% CI, 0.76-0.79; P < 0.001). There was a 23% reduction in the disparity between African Americans and whites after the policy change (interaction aRR, 1.23; 95% CI, 1.18-1.29; P < 0.001). LIMITATIONS: As an observational study, findings could have been affected by residual confounding or other changes in practice patterns. CONCLUSIONS: Racial disparity in rates of DDKT was decreased by the HLA-B policy change, but parity was not achieved. There are unaddressed factors in kidney allocation that lead to continued disparity on the kidney transplant waiting list.

BACKGROUND AND OBJECTIVES: Use of incompatible kidney transplantation (IKT) is growing as a response to the organ shortage and the increase in sensitization among candidates. However, recent regulatory mandates possibly threaten IKT, and the potential effect of these mandates cannot be estimated because dissemination of this modality remains unknown. The goal of this study was to better understand practice patterns of IKT in the United States. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Directors from all 187 unique active adult kidney transplant programs were queried about transplantation across the following antibody barriers: positive Luminex, negative flow crossmatch (PLNF); positive flow, negative cytotoxic crossmatch (PFNC); positive cytotoxic crossmatch (PCC); and ABO incompatible (ABOi). RESULTS: Responses from 125 centers represented 84% of the live-donor transplant volume in the United States. Barriers of PLNF, PFNC, PCC, and ABOi are being crossed in 70%, 51%, 18%, and 24%, respectively, of transplant centers that responded. Desensitization was performed in 58% of PLNF, 76% of PFNC, 100% of PCC, and 80% of ABOi using plasmapheresis and low-dose intravenous Ig (IVIg) in 71% to 83% and high-dose IVIg in 29% to 46%. CONCLUSIONS: A higher proportion of centers perform IKT than might be inferred from the literature. The rapid dissemination of these protocols despite adequate evidence of a clear advantage of IKT transplants argues for the creation of a national registry and randomized studies.