KoreaN cohort study for Outcomes in patients With Kidney Transplantation (KNOW-KT): a prospective observational cohort study focusing on graft outcomes and posttransplant complications.

Background: The KoreaN cohort study for Outcome in patients With Kidney Transplantation (KNOW-KT) is a prospective, multicenter observational cohort designed to provide detailed information on the natural course of kidney transplantation (KT) and to identify risk factors for posttransplant complications. We aimed to describe graft outcomes and long-term posttransplant complications from the KNOW-KT study. Methods: KNOW-KT enrolled 1,115 transplant recipients between 2012 and 2016 and followed them for up to 11 years. Data and biological samples were collected from both transplant recipients and donors at baseline and during annual follow-up visits. Epidemiological factors, laboratory data, allograft outcomes, and patient outcomes, including posttransplant complications, comorbidities, and mortality, were analyzed. Results: A total of 1,080 kidney transplants were registered (86.9% from living donors) with a mean recipient age of 45.8±11.6 years. ABO- and human leukocyte antigen-incompatible transplants accounted for 17.4% and 8.1% of cases, respectively, and 26.7% of recipients underwent pretransplant desensitization. The overall 1-, 5-, and 10-year graft survival rates were 98.5%, 95.0%, and 91.9%, respectively. During a median follow-up period of 9.8 years, graft failure occurred in 7.6% of recipients, while biopsy-proven acute rejection episodes were observed in 19.4%. The cumulative incidence of new-onset malignancy and infection was 7.3 per 1,000 person-years and 41.2 per 1,000 person-years, respectively. Conclusions: The KNOW-KT study characterizes the epidemiology of Korean kidney transplant recipients and provides robust, reliable information on long-term posttransplant outcomes.