Improvement in late renal allograft survival between 1990 and 2002 in Spain: results from a multicentre case-control study

Epidemiological studies have failed to show an improvement in graft survival beyond 1 year after kidney transplantation possibly because of an increased number of expanded donors and older recipients. Thus, we performed a case-control study matching patients transplanted in different eras by donor and recipient characteristics. We considered renal transplant recipients included in the database of the Spanish Chronic Allograft Dysfunction Study Group in 1990, 1994, 1998 and 2002 (n = 4842). We matched patients from these cohorts considering the following variables: donor and recipient age, cause of donor death, hepatitis C virus, panel reactive antibodies and re-transplantation. We identified a total of 896 patients distributed in four cohorts of 224 matched patients. Between 1990 and 2002, the use of cyclosporin decreased (96%, 94%, 80% and 23% respectively, P = 0.001), while the use of tacrolimus increased (0%, 1%, 15% and 63% respectively, P = 0.001) and the prevalence of acute rejection decreased (46%, 37.9%, 20.6% and 15.8% respectively, P < 0.001). One-year serum creatinine was 1.63 +/- 0.66, 1.64 +/- 0.70, 1.44 +/- 0.52 and 1.38 +/- 0.75 respectively, P = 0.001. Graft survival beyond the first year between 1990 and 2002 significantly improved while patient survival did not. Transplant outcome has improved between 1990 and 2002 when donors and recipients of similar characteristics are compared.