ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on Twitter

Kidney Week

Abstract: FR-PO808

Measured Glomerular Filtration Rate Compared to Creatinine and Cystatin C Estimating Equations in Predicting Graft Failure, Cardiovascular Events, and Death in Kidney Transplant (KTx) Recipients

Session Information

Category: Transplantation

  • 2002 Transplantation: Clinical

Authors

  • Keddis, Mira T., Mayo Foundation for Medical Education and Research, Scottsdale, Arizona, United States
  • Howard, Matthew, Mayo Foundation for Medical Education and Research, Scottsdale, Arizona, United States
  • Zhang, Nan, Mayo Foundation for Medical Education and Research, Scottsdale, Arizona, United States
  • Butterfield, Richard J., Mayo Foundation for Medical Education and Research, Scottsdale, Arizona, United States
  • Rule, Andrew D., Mayo Foundation for Medical Education and Research, Scottsdale, Arizona, United States
Background

We compared CysC eGFR, Cr eGFR, Cr-CysC eGFR and measured GFR in predicting graft failure, cardiovascular (CV) events, and death in a cohort of KTx recipients.

Methods

Consecutive adults that received a KTx between 2011-2013 at a single center were evaluated. CysC eGFR, Cr eGFR, Cr-CysC eGFR, and mGFR by urinary iothalamate clearance were obtained at the same time at least 1 year after KTx. The risk of graft failure or of CV events or death with eGFR was assessed after adjusting for mGFR, and for risk factors (recipient age, diabetes, serum albumin, hemoglobin, deceased donor transplant, 24-hour urine protein, and history of CV events).

Results

There were 1148 recipients: mean age 56.0 years, 56% male, 35% with diabetes, 94% with hypertension, 11% with prior history of CV events, 53% required dialysis, and 76% received living donor KTx. After a median follow-up of 74 months, there were 203(18%) graft failures, 229(20%) deaths, and 290(25%) CV events. Graft failure and CV events or death were predicted by lower GFR by any method (Figure 1). After adjusting for mGFR, CysC eGFR and Cr-CysC eGFR but not Cr eGFR were predictive of graft failure. After adjusting for risk factors, CysC eGFR and Cr-CysC eGFR remained predictive of graft failure. After adjusting for mGFR, CysC eGFR and Cr-CysC eGFR but not Cr eGFR were predictive of CV events or death. After further adjusting for risk factors, CysC and Cr-CysC eGFR no longer predicted CV events or death.

Conclusion

In KTx recipients, Cr eGFR predicts clinical outcomes via the same pathway as mGFR, whereas CysC eGFR and Cr-CysC eGFR predict these same outcomes via both GFR and non-GFR pathways. The risk of CV events or death via the non-GFR biology of CysC appears to be via the same pathway as risk factors for CV disease. These findings do not support the routine use of CysC based eGFR in KTx recipients due to its non-GFR biology that distorts the prediction outcomes.

Figure 1