Access to renal transplantation in the diabetic population-effect of comorbidities and body mass index

Background In this study, we hypothesized that higher level of comorbidity and greater body mass index (BMI) may mediate the association between diabetes and access to transplantation. Methods We used data from the United States Renal Data System (01/01/200024/09/2007; n = 619 151). We analyzed two outcomes using Cox model: (i) time to being placed on the waiting list or transplantation without being listed and (ii) time to transplantation after being listed. Two primary Cox models were developed based on different levels of adjustment. Results In Cox models adjusted for a priori defined potential confounders, history of diabetes was associated with reduced transplant access (compared with non-diabetic population) both for wait-listing/transplant without being listed (hazard ratio, HR = 0.80, p < 0.001) and for transplant after being listed (HR = 0.72, p < 0.001). In Cox models adjusted for BMI and comorbidity index along with the potential confounders, history of diabetes was associated with shorter time to wait-listing or transplantation without being listed (HR = 1.07, p < 0.001), and there was no significant difference in time to transplantation after being listed (HR = 1.01, p = 0.42). Conclusion We demonstrated that higher level of comorbidity and greater BMI mediate the association between diabetes and reduced access to transplantation.