Korean J Transplant.  2022 Nov;36(Supple 1):S235. 10.4285/ATW2022.F-3757.

Pretransplant C-reactive protein-to-albumin ratio predicts mortality in kidney transplant recipients: a retrospective cohort study

• Kwon J
• Park SD
• Jeon YH
• Jung HY
• Choi JY
• Park SH
• Kim CD
• Kim YL
• Cho JH
• Lim JH

• KMID: 2535452
• DOI: http://doi.org/10.4285/ATW2022.F-3757

Abstract

Background
C-reactive protein (CRP)-to-albumin ratio (CAR) has been reported as a more effective prognostic indicator than CRP or albumin alone in various diseases. However, the association between CAR and transplant outcomes was not studied in kidney transplantation (KT). This study aimed to evaluate the predictive value of CAR in kidney transplant recipients (KTRs).
Methods
A total of 924 patients who underwent the first KT in the Kyungpook National University Hospital from January 2006 to August 2020 were retrospectively analyzed. KTRs were classified into quartile groups according to the pretransplant CAR value. A multivariate Cox proportional hazard regression analysis was applied to compare the hazard ratio (HR) of mortality by CAR groups.
Results
Fifty-nine patients died during the mean posttransplant period of 85.2±44.2 months. The incidence of all-cause death increased linearly according to the increase of CAR quartile (quartile 1, 3.0%; quartile 2, 4.8%; quartile 3, 7.8%; quartile 4, 10.0%; P=0.001) (Figure 1). The incidence of infection-related death also increased according to the increase of CAR quartile (quartile 1, 0.9%; quartile 4, 5.2%; P= 0.004). After adjusting for confounding factors, quartile 3 and quartile 4 groups showed increased risk of all-cause mortality compared to the quartile 1 (quartile 3, HR, 2.49; 95% confidence interval [CI], 1.04–5.99; P=0.041; quartile 4, HR, 3.09; 95% CI, 1.31–7.27; P=0.010). Quartile 4 was also independently associated with infection-related mortality (HR, 5.83; 95% CI, 1.27–26.8; P=0.023). The area under the curve of the CAR was higher than CRP or albumin alone in receiver operating characteristic curve for all-cause death and infection-related death both. CAR was not related with allograft failure or acute rejection.
Conclusions
A higher pretransplant CAR is associated with increased risk of posttransplant mortality, especially with infection-related mortality. CAR can be a useful predictor of mortality in KTRs.