Patient survival and cardiovascular risk after kidney transplantation: the challenge of diabetes

Abstract

An increasing proportion of kidney recipients have diabetes mellitus (DM). Herein, we assessed the impact of DM on morbidity and mortality. The study included 933 recipients of first transplants. DM was present in 212 (23%). Compared to non-diabetics (NoDM), DM were older, heavier and had more pretransplant cardiovascular (CV) disease (16% vs. 48%, p < 0.0001). DM had reduced survival (5 years, 93% vs. 70%, p < 0.0001) and higher incidence of CV events (9% vs. 37%, p < 0.0001). CV disease was the most common cause of death in DM (61%) but not in NoDM (26%). Mortality from infections was also higher in DM (p = 0.001). In NoDM, survival related to recipient age (hazard ratio (HR) = 1.07, p < 0.0001) and dialysis pretransplant HR = 2.21, p = 0.01, while in DM, survival related to dialysis (HR = 2.89, p = 0.01) and pretransplant CV disease (HR = 2.79, p = 0.007). In NoDM, the incidence of posttransplant CV events was related to traditional CV risk factors, while in DM only the pretransplant CV history related to this outcome. In conclusion, survival differs between NoDM and DM recipients quantitatively, by cause of death and by risk factors. In NoDM, survival is excellent, and the main threat to survival relates to immunosuppression. In DM, survival is inferior primarily due to CV disease generally present prior to transplantation.