Skin-autofluorescence is an independent predictor of graft loss in renal transplant recipients.
BACKGROUND
Skin-autofluorescence (skin-AF) noninvasively measures the tissue accumulation of advanced glycation end products (AGEs). AGEs are nephrotoxic and potential effectors of cardiovascular mortality. We investigated whether skin-AF predicted graft loss after kidney transplantation.


METHODS
A total of 302 renal transplant recipients were enrolled at a median time of 6.1 (2.6-12.1) years after transplantation and were subsequently followed up for first occurrence of graft loss (i.e., graft failure or all-cause mortality) for 5.2 (4.6-5.4) years. The association of baseline skin-AF with graft loss was investigated with univariable and multivariable Cox-regression and receiver-operator-characteristic curve analyses.


RESULTS
Baseline skin-AF was 2.7+/-0.8 arbitrary units. Skin-AF predicted graft loss in a univariable Cox regression analysis (Hazard ratios 2.40 [1.75-3.29], P<0.001) and in a multivariable model (Hazard ratios 1.83 [1.22-2.75], P=0.003), adjusted for other identified risk-factors, including patient age, creatinine clearance, protein excretion, high sensitivity C-reactive protein (hsCRP), and human leukocyte antigen-DR mismatching. The area under the receiver-operator-characteristic curve for skin-AF as predictor of graft loss was significantly different from 0.5. Skin-AF was also a significant predictor of graft failure and mortality as separate end points.


CONCLUSIONS
We conclude that skin-AF is an independent predictor of graft loss in kidney transplant recipients. Although skin-AF is not a direct measurement for AGEs, we believe that our results do support the hypothesis that accumulation of AGEs in renal transplant recipients contributes to the development of graft loss.
Hartog
Jasper W L
JW
Department of Internal Medicine, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands.
Gross
Sascha
S
Oterdoom
Leendert H
LH
van Ree
Rutger M
RM
de Vries
Aiko P J
AP
Smit
Andries J
AJ
Schouten
Jan P
JP
Nawroth
Peter P
PP
Gans
Reinold O B
RO
van Son
Willem J
WJ
Bierhaus
Angelika
A
Bakker
Stephan J L
SJ
D000328:Adult; D000368:Aged; D005260:Female; D005453:Fluorescence; D006085:Graft Survival; D006801:Humans; D007676:Kidney Failure, Chronic / Q000601:surgery*; D016030:Kidney Transplantation / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D011237:Predictive Value of Tests; D012044:Regression Analysis; D012189:Retrospective Studies; D012867:Skin / Q000473:pathology*; D016019:Survival Analysis; D014019:Tissue Donors / Q000706:statistics & numerical data; D017211:Treatment Failure