Trends in serum creatinine levels and transplant year.

The serum creatinine (SCr) level has a strong predictive value for kidney graft survival. On average, the SCr levels of recipients whose grafts continued to function were lower (< 1.5 mg/dl) than those for recipients who died with a functioning graft during the following year (-2.0 mg/dl) and were much lower than those for recipients whose graft failed within a year due to chronic rejection (-3.0 mg/dl). The average one-year SCr levels have fallen steadily since 1995 among recipients of living and deceased donor kidney transplants, suggesting that immunosuppression and clinical management have improved graft function. These improvements have come despite increasing transplantation of older donor kidneys and heavier recipients, both of which are factors predisposing to higher SCr levels. Even though the average one-year SCr levels have dropped over the past 10 years, there has not been a substantial improvement in long-term graft survival.