Development of post-transplant diabetes mellitus in US Liver Transplant recipients is influenced by OPTN region

Background: Post-transplant diabetes mellitus (PTDM) is associated with significant morbidity and mortality in liver transplant recipients (LTRs). We utilized the Organ Procurement and Transplantation Network (OPTN) database to compare incidence of developing PTDM across the US and develop a risk prediction model for new-onset PTDM using OPTN region as well as donor-, recipient-, and transplant-related factors. Methods: All US adult, primary, deceased donor, LTRs between January 1, 2007, and December 31, 2016, with no prior history of diabetes noted , were identified. Kaplan Meier estimators were utilized to calculate cumulative incidence of PTDM, stratified by OPTN region. Multivariable Cox-proportional hazards models were fitted to estimate hazards of PTDM in each OPTN region and build a risk prediction model, via backward selection. Results: Cumulative incidence of PTDM at 1-year, 3-years and 5-years post-transplant was 12.0%, 16.1%, and 18.9%, respectively. Region 3, followed by region 8, 2 and 9, had the highest adjusted hazards of developing PTDM. Inclusion of OPTN region in a risk prediction model for PTDM in LTRs (including recipient age, sex, race, education, insurance coverage, BMI, primary liver disease, cold ischemia time and donor history of diabetes), modestly improved performance (C-statistic=0.60). Conclusions: In patients without pre-existing, confirmed DM, the incidence of PTDM in LTRs varied across OPTN regions, with highest hazards in region 3, followed by region 8, 2 and 9. Performance of a novel risk prediction model for PTDM in LTRs has improved performance with the inclusion of OPTN region. Vigilance is recommended to centers in high-risk regions to identify PTDM and mitigate its development.