[Multivariate analysis of graft survival prognostic factors in renal transplantation]

The aim of this paper is to identify the variables that could be of interest in the outcome of a series of cadaveric kidney transplantation performed at the University Hospital, Navarra School of Medicine, by means of multifactorial and multivariate statistical analyses.

We analyzed 307 cadaveric kidney transplantation performed since 1976 at the University Hospital, School of Medicine, University of Navarra. Two series are included: the historical and the actual. The former did not include cyclosporine A in the immunosuppressor protocol.

The first step was to compare survival in both series. The cyclosporine A series had a better survival, which was statistically significant (p < 0.0001). The prognostic factors in both series were also analyzed. The influence of the different variables were studied in the survival distribution. The worse prognostic variables of the historical group on allograft survival were donor's age (particularly between 20 and 50 years old), delayed graft function, serum creatinine level greater than 2.5 mg/dl at the first month following transplantation, general surgical complications, and vascular and other complications. In the actual group, the allografts with the worst survival were in those that received 4-10 pre-transplant blood transfusions, those with more that 2 HLA-DR mismatches, the hyperimmunized receptors with a level of pre-formed cytotoxic antibodies greater than 50%, those who rejected the allograft in the initial post-transplant period, those with a serum creatinine level greater than 2.5 mg/dl and those who presented surgical complications in general and urinary and vascular complications in particular.

The multivariate analysis reveals that the prognostic factors of the historical group were delayed graft function, surgical complications, HLA A+B mismatches and the donor's age. In the actual group, the factors were receptor's age, surgical complications, large ischemia time, peak reactive antibody and number of rejections.