There are few data available on the role diabetes type 1 and type 2 plays in modifying prognosis in kidney transplant recipients. Jessica Harding, MD, and colleagues conducted a study to compare mortality among kidney transplant recipients with type 1 diabetes, type 2 diabetes, and non-diabetes-related end-stage kidney disease (ESKD). Results were reported online in BMJ Open Diabetes & Research Care [doi:10.1136/bmjdrc-2020-001962].
The study included 254,188 first-time single kidney transplant recipients ≥18 years of age who were identified from the US Renal Data System database (2000-2018). International Classification of Diseases, 9th and 10th Clinical Modification codes were used to define diabetes status as primary cause of ESKD. The risk of death associated with type 1 and type 2 diabetes relative to non-diabetes was calculated using multivariable Cox regression models (right-censored). Trends in standardized mortality ratios (SMRs) (2000-2017), relative to the general US population, were assessed using Joinpoint regression.
Median survival time was 14.6 years, over which 72,175 (28.4%) deaths occurred. Five-year survival probabilities were 88% for non-diabetes, 85% for type 1 diabetes, and 77% for type 2 diabetes. Following adjustment, mortality was highest in the type 1 diabetes group (hazard ratio [HR], 1.95; 95% confidence interval [CI], 1.88-2.03) and then type 2 diabetes (HR. 1.65; 95% CI, 1.62-1.69), as compared with non-diabetes.
SMRs declined for all three groups. The SMRs in 2017 were 2.38 (95% CI, 2.31-2.45) for non-diabetes, 6.55 (95% CI, 6.07-7.06) for type 1 diabetes, and 3.82 (95% CI, 3.68-3.98) for type 2 diabetes.
The researchers said, “In the USA, diabetes type is an important modifier in mortality risk among kidney transplant recipients with highest rates among people with type 1 diabetes-related ESKD. Development of effective interventions that reduce excess mortality in transplant recipients with diabetes is needed, especially for type 1 diabetes.”