The relationship between kidney function and long-term graft survival after kidney transplant.
BACKGROUND
Whether chronic kidney disease (CKD) staging provides a useful framework for predicting outcomes after kidney transplant is unclear.


METHODS
Retrospective cohort study.


METHODS
We used data from the Patient Outcomes in Renal Transplantation (PORT) Study, including 13,671 transplants from 12 centers during 10 years of follow-up.


METHODS
Estimated glomerular filtration rate (eGFR; in milliliters per minute per 1.73 m(2)) at 12 months posttransplant.


RESULTS
All-cause graft failure (a composite end point consisting of return to dialysis therapy, pre-emptive retransplant, or death with function), death-censored graft failure, and death with a functioning graft.


METHODS
The relationship between 12-month eGFR and subsequent graft outcomes through 10 years posttransplant was assessed using Cox proportional hazards analyses.


RESULTS
Stage 3 included 63% of patients and was subdivided into stages 3a (eGFR, 45-59 mL/min/1.73 m(2); 34%) and 3b (eGFR, 30-44 mL/min/1.73 m(2); 29%). Compared with stage 2 (eGFR, 60-89 mL/min/1.73 m(2); 24%), adjusted Cox proportional HRs for graft failure were 1.12 (95% CI, 1.01-1.24; P = 0.04) for stage 3a, 1.50 (95% CI, 1.35-1.66; P < 0.001) for stage 3b, 2.86 (95% CI, 2.53-3.22; P < 0.001) for stage 4 (eGFR, 15-29 mL/min/1.73 m(2); 9%), and 13.2 (95% CI, 10.7-16.4; P < 0.001) for stage 5 (eGFR <15 mL/min/1.73 m(2); 1%). For stage 1 (eGFR ≥ 90 mL/min/1.73 m(2); 3%), risk of graft failure was increased (1.41 [95% CI, 1.13-1.75]; P < 0.001), likely due to serum creatinine associations independent of kidney function. Similar associations were seen between CKD stages and mortality.


CONCLUSIONS
Retrospective study; lack of gold-standard measurements of true GFR; lack of measures of comorbidity, inflammation, muscle mass, proteinuria, and other noncreatinine markers of eGFR.


CONCLUSIONS
CKD stages validated in the general population provide a useful framework for predicting outcomes after kidney transplant.
Chronic Disease Research Group, Minneapolis Medical Research Foundation, Minneapolis, MN, USA. kasis001@umn.edu
Bertram L
BL
Kasiske
Ajay K
AK
Israni
Jon J
JJ
Snyder
Melissa A
MA
Skeans
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006084:Graft Rejection / Q000453:epidemiology*; D006085:Graft Survival; D006801:Humans; D015994:Incidence; D007676:Kidney Failure, Chronic / Q000601:surgery*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D055815:Young Adult