Clinical implications of Type 2 diabetes on outcomes after cardiac transplantation

T2D is an increasingly common disease that is associated with worse outcomes in patients with heart failure. Despite this, no contemporary study has assessed its impact on heart transplantation outcomes. This paper examines the demographics and outcomes of patients with type 2 diabetes (T2D) undergoing heart transplantation.

Using the United Network for Organ Sharing (UNOS) database, patients listed for transplant were separated into cohorts based on history of T2D. Demographics and comorbidities were compared, and cox regressions were used to examine outcomes.

Between January 1st, 2011 and June 12th, 2020, we identified 9,086 patients with T2D and 23,676 without T2D listed for transplant. The proportion of patients with T2D increased from 25.2% to 27.9% between 2011 and 2020. Patients with T2D were older, more likely to be male, less likely to be White, and more likely to pay with public insurance (p<0.001, all). After adjustment, T2D patients had a lower likelihood of transplantation (Hazard Ratio [HR]: 0.93, CI: 0.90-0.96, p<0.001) and a higher likelihood of post-transplant mortality (HR: 1.30, CI: 1.20-1.40, p<0.001). Patients with T2D were more likely to be transplanted in the new allocation system compared to the old allocation system (all, p<0.001).

Over the last ten years, the proportion of heart transplant recipients with T2D has increased. These patients are more likely to be from traditionally underserved populations. Patients with T2D have a lower likelihood of transplantation and a higher likelihood of post-transplant mortality. After the allocation system change, likelihood of transplantation has improved for patients with T2D.