Abstract: SA-PO515

Low Post-Transplant 1-Year Tacrolimus Level Is Associated with Poor Renal Allograft Survival in Kidney Transplant Patients

Session Information

Category: Transplantation

  • 1702 Transplantation: Clinical and Translational

Authors

  • Ryu, Jung-hwa, Seoul National University Hospital, Seoul, Korea (the Republic of)
  • Koo, Tai yeon, Seoul National University Hospital, Seoul, Korea (the Republic of)
  • Min, Kyungok, Seoul National University Hospital, Seoul, Korea (the Republic of)
  • Yang, Jaeseok, Seoul National University Hospital, Seoul, Korea (the Republic of)
Background

Symphony study demonstrated that low-dose tacrolimus therapy with trough level between 3 to 7 ng/ml can achieve the best short-term renal allograft outcomes. However, it is still controversial that low tacrolimus exposure has good impact on long-term graft outcomes. Here, we investigated the association of tacrolimus trough-level at 1 year after kidney transplantation and graft survival rate.

Methods

This retrospective observation study included patients older than 18 year who underwent kidney transplantation under tacrolimus-based regimens in the Seoul university hospital between April 30, 1997 and June 8, 2016. Kaplan-Meier survival analysis and multivariate Cox regression analysis were performed according to tacrolimus trough-levels within 1 month and at 1 year after kidney transplantation.

Results

A total of 865 kidney transplant patients were included and 46 grafts failed during the study period. Tacrolimus levels < 7 ng/mL at 1 year after transplantation were associated with worse death-censored graft survival (Figure, P = 0.017). In multivariate analysis, tacrolimus < 7 ng/mL was an independent risk factor for poor graft survival (HR 0.469: 95% C.I. 0.235-0.936, P = 0.032). Furthermore, tacrolimus level < 7 ng/mL within 1 month was also associated with worse 10-year graft survival (P=0.007). However, there was no significant association between post-transplant 1-year tacrolimus levels and patient survival rate.

Conclusion

Keeping sufficient tacrolimus level (≥ 7 ng/mL) at 1 year after transplantation is beneficial for good long-term allograft survival.

Figure. Renal allograft survival rates according to tacrolimus level of 7 ng/mL at 1 year after transplantation.