Objective: To investigate temporal trends and compare outcomes between Black and Caucasian kidney transplant recipients in the UK from 2000 to 2019.
Design: A retrospective cohort study utilising national registry data (COBIT-UK) was conducted. The study employed a robust statistical methodology, including Cox regression analysis, to quantify the association between ethnicity and outcomes while adjusting for relevant covariates.
Setting: The study was based on data from the UK Transplant Registry, which encompasses a comprehensive database of transplant recipients across the United Kingdom.
Participants: The study included a total of 19,385 first-time kidney transplant recipients, comprising 1,878 (9.7%) black and 17,507 (90.3%) caucasian individuals.
Main Outcome Measures: The primary outcomes of interest were graft failure and mortality rates among the study participants.
Methods:  20-year (2000–2019) retrospective cohort study analysed UK Transplant Registry data using descriptive statistics and Cox regression, adjusting for covariates. Graft and patient survival were compared between black and caucasian adult kidney transplant recipients.
Results: Temporal trends in transplantation were assessed using descriptive statistics. The annual number of transplants among black recipients increased significantly from 49 to 250 over the study period (p<0.001). However, black recipients were less likely to receive living donor transplants compared to their caucasian counterparts (9.7% vs. 25.6%, OR 0.43, 95% CI 0.39–0.48, p<0.001).The adjusted graft survival at 5 years post-transplantation showed no significant difference between black and Caucasian recipients (HR 1.04, 95% CI 0.89–1.21, p = 0.64). Notably, black patients on the waitlist experienced a higher mortality rate compared to Caucasian patients (HR 1.56, 95% CI 1.32-1.85, p<0.001). However, transplantation provided a significant survival benefit for black recipients (HR 0.42, 95% CI 0.35-0.51, p<0.001).
Conclusions: While progress has been made in improving equity in kidney transplant access and outcomes for black patients in the UK, residual disparities persist. The COBIT-UK study highlights the need for continued efforts to address these disparities and ensure optimal care for all kidney transplant recipients, regardless of ethnicity.