Early post-transplant renal allograft function between 1990 and 1998 in Spain.

Background: The last decade has witnessed a sustained improvement of renal allograft survival that is partly explained by a better preservation of renal allograft function. This study describes time-dependent modifications of serum creatinine (SCr) during the first year after transplantation in the last decade in Spain and characterizes the predictive value of SCr on death-censored graft survival.

Methods: A total of 3365 adult patients transplanted in 1990 (n = 824), 1994 (n = 1075) and 1998 (n = 1466) with a functioning graft after the first year were included. Renal function deterioration during the first year was expressed as the difference between SCr at 1 year and SCr at 3 months.

Results: Despite the projected renal allograft half-life, estimation was significantly higher in 1998 than in 1990 (17.7 vs 15.4 years, P = 0.007), the SCr levels at 3 months were significantly lower in 1990 (1.59+/-0.64) than in 1998 (1.65+/-0.66). While SCr tended to worsen during the first year in 1990 (0.05+/-0.64) it improved in 1998 (-0.003+/-0.48), P = 0.0001. The following variables were significantly associated with SCr at 3 months: donor age and sex, cause of death, recipient sex, time on dialysis, cold ischaemia time, delayed graft function, acute rejection, cytomegalovirus infection and reintervention for any reason. Renal function deterioration during the first year was associated with the presence of acute rejection and hepatitis C virus antibodies in the recipient.

Conclusions: Despite poorer renal function at 3 months in 1998 than in 1990, renal allograft survival has improved in Spain between 1990 and 1998. This result is partly explained by a slower deterioration of renal function during the first year of follow-up.