Are older deceased donors an underused resource?
By Martina M. McGrath, MD
December, 29, 2016
Since publication of Robert Wolfe’s landmark paper in 19991 demonstrating a doubling of life expectancy post-renal transplantation compared with remaining on dialysis, demand for renal transplants has continuously grown. Over 99,000 individuals are currently awaiting renal transplantation in the US.2 Kidneys from deceased donors previously termed ‘extended criteria donors’ (ECD), provide good outcomes with acceptable duration of function for selected, older recipients or those not expected to survive on long-term dialysis. ECD kidneys come from donors over 60 years old or from those aged 50-59 years old with coexisting medical conditions such as hypertension, cerebrovascular disease, or creatinine >1.5mg/dL. Despite good short-term outcomes, the rates of discard for these kidneys remain high. For those in the transplant community, these kidneys may be a precious resource that is being wasted. So the question remains—when it comes to deceased donation, how old is too old?
Messina et al from Turin, Italy recently addressed this question. They analyzed data from 647 consecutive ECD kidneys used at their center over a 10-year period. Donors were stratified by age (group A: 50-59 years, group B: 60-69 years, group C: 70-79 years and group D: >80 years old) with follow up for almost five years.
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Patient and graft survival were similar across all groups, with graft survival varying from 74 percent in group A at 5 years, to 65.9 percent in group D. Multivariate analysis showed worse graft outcomes were associated with delayed graft function (DGF), acute rejection, and CMV reactivation. Donor age did not have a significant impact on graft outcomes. However, patients who received double (i.e. got both kidneys from a given donor) as opposed to single kidney transplant from donors in group D did significantly better. This difference was not observed in other donor groups.
Several factors are worthy of note. These were well-matched, immunologically low-risk transplants where 88-90 percent of recipients were unsensitized. Pre-implantation biopsies showed little fibrosis and vascular disease. Kidneys with greater degrees of chronic damage were discarded; as expected, with greater frequency in group D.
The findings from this study are quite encouraging, and demonstrate that ECD kidneys from donors aged in their 50s to late 70s have similar outcomes. The positive five-year data from donors over 80 years old will surprise many in the field, but this strategy is not without risk; there was a 7.4 percent rate of primary nonfunction (2/27 kidneys) and almost 60 percent incidence of DGF, which can portend poorer long-term outcomes. However, the data clearly suggests that in carefully selected cases, and given to low immunologic risk, well-informed patients, ECD kidneys including those from donors of more advanced age can provide freedom from dialysis with acceptable medium-term outcomes.
- Robert A. Wolfe, Ph.D., Valarie B. Ashby, M.A., Edgar L. Milford, M.D et al. Comparison of Mortality in All Patients on Dialysis, Patients on Dialysis Awaiting Transplantation, and Recipients of a First Cadaveric Transplant. N Engl J Med 1999; 341:1725-1730
- https://www.unos.org/data/transplant-trends/waiting-list-candidates-by-organ-type. Accessed Dec 21st 2016.
- Maria Messina, Davide Diena, Sergio Dellepiane, Gabriella Guzzo, Luca Lo Sardo, Fabrizio Fop, Giuseppe P. Segoloni, Antonio Amoroso, Paola Magistroni, and Luigi Biancone. Long-Term Outcomes and Discard Rate of Kidneys by Decade of Extended Criteria Donor Age. CJASN CJN.06550616; published ahead of print December 15, 2016.
Dr. Martina McGrath is an Instructor in Medicine at Harvard Medical School, and a member of the Renal Division, Department of Medicine, at Brigham and Women’s Hospital, both in Boston. Dr. McGrath is the Medical Editor for the Trends in Medicine blog.