title: The combination of donor and recipient age is critical in determining host immunoresponsiveness and renal transplant outcome.
abstract: OBJECTIVE
  To evaluate the interaction of donor and recipient age on transplant outcome and immune response.
  
  
  BACKGROUND
  The age of donor and recipient is becoming increasingly important in organ transplantation. We tested the relevance and consequences of recipient and donor age on immunoresponsiveness and transplant outcome in a uni- and multilateral cohort analysis.
  
  
  METHODS
  We obtained and analyzed data from 108,188 recipients of deceased donor kidneys of the United Network for Organ Sharing database transplanted between 1995 and 2008. Univariate analysis of allograft and patient survival was calculated by Kaplan Meyer. Multivariate analyses were performed using the Cox Proportional Hazards method. Data were assessed and compared by decades of increasing donor and recipient age with and without censoring transplant loss for death with a functioning graft. This approach allowed a detailed analysis of interacting factors.
  
  
  RESULTS
  Transplant survival was lowest in elderly recipients. However, when the analysis was censored for patient's death with a functioning kidney transplant, survival improved incrementally with each decade of increasing recipient age. This was even more surprising as older recipients had received less well-matched organs of poorer quality. The frequency of acute rejection decreased dramatically with increasing age, emphasizing the effect of age on the vigor of the recipient's immune responses. In contrast, increasing donor age was associated with more frequent acute rejection rates. The effects of donor and recipient age in combination demonstrated that grafts of older donors fared significantly better in older recipients.
  
  
  CONCLUSIONS
  Our results show that increasing recipient age is associated with an improved transplant survival, lower rates of rejection, and superior outcome of older donor organs. Physiological and/or immunologic aspects of organ and recipient age seem to determine, at least in part, the success of renal transplantation.
authors.affiliation: Division of Transplant Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. stullius@partners.org
authors.forename: Stefan G
authors.initials: SG
authors.lastname: Tullius
authors.forename: Huong
authors.initials: H
authors.lastname: Tran
authors.forename: Indira
authors.initials: I
authors.lastname: Guleria
authors.forename: Sayeed K
authors.initials: SK
authors.lastname: Malek
authors.forename: Nicholas L
authors.initials: NL
authors.lastname: Tilney
authors.forename: Edgar
authors.initials: E
authors.lastname: Milford
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006084:Graft Rejection / Q000503:physiopathology; D006085:Graft Survival / Q000502:physiology; D006801:Humans; D007121:Immunocompetence; D016030:Kidney Transplantation / Q000276:immunology* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D014019:Tissue Donors; D016896:Treatment Outcome