The Korean Organ Transplantation Registry (KOTRY): an overview and summary of the kidney-transplant cohort

Abstract

Background: As the need for a nationwide organ-transplant registry emerged, a prospective registry, the Korean Organ Transplantation Registry (KOTRY), was initiated in 2014. Here, we present baseline characteristics and outcomes of the kidney-transplant cohort for 2014 through 2019.

Methods: The KOTRY consists of five organ-transplant cohorts (kidney, liver, lung, heart, and pancreas). Data and samples were prospectively collected from transplant recipients and donors at baseline and follow-up visits; and epidemiological trends, allograft outcomes, and patient outcomes, such as posttransplant complications, comorbidities, and mortality, were analyzed.

Results: From 2014 to 2019, there were a total of 6,129 registered kidney transplants (64.8% with living donors and 35.2% with deceased donors) with a mean recipient age of 49.4 ± 11.5 years, and 59.7% were male. ABO-incompatible transplants totaled 17.4% of all transplants, and 15.0% of transplants were preemptive. The overall 1- and 5-year patient survival rates were 98.4% and 95.8%, respectively, and the 1- and 5-year graft survival rates were 97.1% and 90.5%, respectively. During a mean follow-up of 3.8 years, biopsy-proven acute rejection episodes occurred in 17.0% of cases. The mean age of donors was 47.3 ± 12.9 years, and 52.6% were male. Among living donors, the largest category of donors was spouses, while, among deceased donors, 31.2% were expanded-criteria donors. The mean serum creatinine concentrations of living donors were 0.78 ± 0.62 mg/dL and 1.09 ± 0.24 mg/dL at baseline and 1 year after kidney transplantation, respectively.

Conclusion: The KOTRY, a systematic Korean transplant cohort, can serve as a valuable epidemiological database of Korean kidney transplants.

Keywords: Cohort studies; Kidney transplantation; Registries; Republic of Korea.

Figure 1.

Baseline characteristics of kidney transplants in KOTRY. (A) The numbers of registered living-donor and deceased-donor kidney transplantations in KOTRY from 2014 to 2019. (B) The causes of end-stage renal disease among total kidney recipients. (C, D) Dialysis modality before living-donor and deceased-donor kidney transplantations according to transplantation year. KOTRY, Korean Organ Transplantation Registry.

Figure 2.

Patient and graft survival of kidney-transplant recipients in KOTRY. (A, B) Patient survival of kidney recipients. (C, D) Graft survival of kidney recipients. KOTRY, Korean Organ Transplantation Registry.

Figure 3.

Posttransplant complications and comorbidities of kidney-transplant recipients in KOTRY. (A) Rejection (biopsy-proven)-free survival rate. Cumulative incidence rates of (B) cardiac events after kidney transplantation, (C) NODAT, (D) malignancy after kidney transplantation, (E) viral infection after kidney transplantation, and (F) nonviral infection after kidney transplantation. KOTRY, Korean Organ Transplantation Registry; NODAT, new-onset diabetes after transplantation.

Figure 4.

Age distribution of living (A) and deceased (B) kidney donors. (C) Donor–recipient relationship among living kidney donors. (D) Expanded-criteria donors among deceased kidney donors according to transplantation year.