Impact of Pretransplant and New-Onset Diabetes After Transplantation on the Risk of Major Adverse Cardiovascular Events in Kidney Transplant Recipients: A Population-based Cohort Study

Background: Pretransplant diabetes and new-onset diabetes after transplant (NODAT) are known risk factors for vascular events after kidney transplantation, but the incidence and magnitude of the risk of major adverse cardiovascular events (MACE) and cardiac deaths remain uncertain in recent era.

Methods: A population cohort study of kidney transplant recipients identified using data from linked administrative healthcare databases from Ontario, Canada. The incidence rates of MACE (expressed as events with 95% confidence interval [95% CI] per 1000 person-years were reported according to diabetes status of pretransplant diabetes, NODAT, or no diabetes. Extended Cox regression model was used to examine the association between diabetes status, MACE, and cardiac death.

Results: Of 5248 recipients, 1973 (38%) had pretransplant diabetes, and 799 (15%) developed NODAT with a median follow-up of 5.5 y. The incidence rates (95% CI) of MACE for recipients with pretransplant diabetes, NODAT, and no diabetes between 1 and 3 y posttransplant were 38.1 (32.1-45.3), 12.6 (6.3-25.2), and 11.8 (9.2-15.0) per 1000 person-years, respectively. Compared with recipients with pretransplant diabetes, recipients with NODAT experienced a lower risk of MACE (adjusted hazard ratio, 0.59; 95% CI, 0.47-0.74) but not cardiac death (adjusted hazard ratio, 0.97; 95% CI, 0.61-1.55). The rate of MACE and cardiac death was lowest in patients without diabetes.

Conclusions: Patients with pretransplant diabetes incur the greatest rate of MACE and cardiac deaths after transplantation. Having NODAT also bears high burden of vascular events compared with those without diabetes, but the magnitude of the increased rate remains lower than recipients with pretransplant diabetes.