Dominant predictors of early post-transplant outcomes based on the Korean Organ Transplantation Registry (KOTRY)

Abstract

Data for Asian kidney transplants are very limited. We investigated the relative importance of prognostic markers in Asian kidney transplants by using Korean Organ Transplantation Registry (KOTRY) cohort. Prediction models were developed by data-driven variable selection approach. The relative importance of the selected predictors was measured by dominance analysis. A total of 4854 kidney transplant donor-recipient pairs were analyzed. Overall patient survival rates were 99.8%, 98.8%, and 91.8% at 1, 3, and 5 years, respectively. Death-censored graft survival rates were 98.4%, 97.0%, and 95.8% at 1, 3, and 5 years. Biopsy-proven acute rejection free survival rates were 90.1%, 87.4%, and 87.03% at 1, 3, and 5 years. The top 3 dominant predictors for recipient mortality within 1 year were recipient cardiovascular disease history, deceased donor, and recipient age. The dominant predictors for death-censored graft loss within 1 year were acute rejection, deceased donor, and desensitization. The dominant predictors to acute rejection within 1 year were donor age, HLA mismatched numbers, and desensitization. We presented clinical characteristics of patients enrolled in KOTRY during the last 5 years and investigated dominant predictors for early post-transplant outcomes, which would be useful for clinical decision-making based on quantitative measures.

Figure 1

Patient (a) and death-censored graft (b) survival of Korean Organ Transplantation Registry.

Figure 2

Acute rejection free- (a) and biopsy-proven acute rejection free- (b) survival of Korean Organ Transplantation Registry.

Figure 3

Hazard ratios of donor age to post-transplantation acute rejection within 1 year. (a) Three dimensional visualization of hazard ratio of donor age according to HLA mismatch numbers in overall study population (b) Two dimensional contour map of the hazard ratio of donor age according to HLA mismatch numbers in overall study population (c) Stratified hazard ratio of donor age in living donor kidney transplantation subpopulation (d) Stratified hazard ratio of donor age in deceased donor kidney transplantation subpopulation. Red line indicates logarithm of hazard ratio of donor age in HLA full match group. Each colored area indicates its 95% confidence interval. Green line indicates logarithm of hazard ratio of donor age in moderate HLA mismatch group (as representative, hazard ratio line of HLA mismatch number 3 is used). Blue line indicates logarithm of hazard ratio of donor age in high HLA mismatch group (hazard ratio line of HLA mismatch number 6 is used). All graphs are the results of multivariable regression analyses which included donor age, HLA mismatch numbers, desensitization, recipient sex, recipient age, donor hypertension, recipient blood pressure, deceased donor, duration of renal replacement therapy, ever smoking in recipients.

Figure 4

Acute rejection-free survival of kidney transplant recipients according to donor age and the types of organ donor. Donor age of 48 years old was selected as the optimal cutoff points among this study population. DDKT, deceased donor kidney transplantation; LDKT, living donor kidney transplantation.

Figure 5

Visualization of log odds of acute rejection within 1 year according to different donor age (a) Visualization of log odds of acute rejection within 1 year according to different donor age in overall study population (b) Stratified log odds of acute rejection within 1 year according to different donor age in living donor kidney transplantation subpopulation (c) Stratified log odds of acute rejection within 1 year according to different donor age in deceased donor kidney transplantation subpopulation. Blue line indicates adjusted logarithm of odds of acute rejection within 1 year according to different donor age in each group. Each grey area indicates its 95% confidence interval. All graphs are the results of multivariable regression analyses which included donor age, HLA mismatch numbers, desensitization, recipient sex, recipient age, donor hypertension, recipient blood pressure, deceased donor, duration of renal replacement therapy, ever smoking in recipients.