Serum Creatinine Level at One Month Post-Transplant Predicts 3-Year and 5-Year Graft Survival and Renal Function: A...

Background: Contemporary kidney transplantation increasingly includes high-immunologic-risk recipients, ABO-incompatible transplantation, deceased-donor transplantation, and desensitization protocols. Although early post-transplant serum creatinine has historically been associated with long-term graft outcomes, its prognostic value in modern high-risk transplant cohorts remains insufficiently characterized. We evaluated whether serum creatinine at one month post-transplant independently predicts 3-year and 5-year graft survival and renal function in a large contemporary kidney transplant cohort. Methods: Among 1895 consecutive KT recipients (2005-2018), patients were stratified by one-month serum creatinine into four quartiles: Q1 (<1.0 mg/dL, n = 398), Q2 (1.0-1.23, n = 480), Q3 (1.23-1.52, n = 487), and Q4 (≥1.52, n = 530). Primary endpoints were 3- and 5-year death-censored graft survival. Results: Median follow-up was 95 months. Three-year graft survival was 97.2%, 96.2%, 95.3%, and 90.3% for Q1-Q4, respectively; 5-year survival was 94.5%, 94.6%, 92.5%, and 86.9%. eGFR stratification persisted at both 3 and 5 years. After adjustment including donor and recipient BMI, Q4 creatinine independently predicted graft failure (HR, 1.590; 95% CI, 1.049-2.412; p = 0.029). One-month serum creatinine also remained significant as a continuous variable (HR, 1.409 per 1.0 mg/dL increase; 95% CI, 1.279-1.551; p < 0.001). ROC analysis identified an optimal cutoff of 1.39 mg/dL (AUC, 0.622; sensitivity, 52.6%; specificity, 65.0%). Conclusions: One-month serum creatinine is a robust and independent predictor of graft survival and renal function after kidney transplantation. These findings support its use as a simple early risk-stratification marker and as a trigger for targeted post-transplant surveillance.