Kidney function and risk of cardiovascular disease and mortality in kidney transplant recipients: The FAVORIT trial

In kidney transplant recipients, cardiovascular disease (CVD) is the leading cause of death. The relationship of kidney function with CVD outcomes in transplant recipients remains uncertain. We performed a post hoc analysis of the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) Trial to assess risk factors for CVD and mortality in kidney transplant recipients. Following adjustment for demographic, clinical and transplant characteristics, and traditional CVD risk factors, proportional hazards models were used to explore the association of estimated GFR with incident CVD and all-cause mortality. In 4016 participants, mean age was 52 years and 20% had prior CVD. Mean eGFR was 49±18 mL/min/1.73 m². In 3676 participants with complete data, there were 527 CVD events over a median of 3.8 years. Following adjustment, each 5 mL/min/1.73 m² higher eGFR at levels below 45 mL/min/1.73 m² was associated with a 15% lower risk of both CVD [HR = 0.85 (0.80, 0.90)] and death [HR = 0.85 (0.79, 0.90)], while there was no association between eGFR and outcomes at levels above 45 mL/min/1.73 m ². In conclusion, in stable kidney transplant recipients, lower eGFR is independently associated with adverse events, suggesting that reduced kidney function itself rather than preexisting comorbidity may lead to CVD. In stable kidney transplant recipients participating in the FAVORIT Trial, lower estimated glomerular filtration rate, beginning at a level of 45 ml/min per 1.73 m ², is independently associated with cardiovascular disease events and all-cause mortality, suggesting that reduced kidney function itself may directly lead to cardiovascular disease independent of preexisting comorbidities.