The Impact of Preexisting Diabetes Mellitus on Chronic Lung Allograft Dysfunction After Lung Transplantation.

BACKGROUND: Chronic lung allograft dysfunction (CLAD) remains a major cause of mortality after lung transplantation. Diabetes mellitus (DM) may contribute to CLAD through metabolic dysregulation. We evaluated post-lung transplant outcomes in recipients with DM. METHODS: Adults undergoing first-time, isolated lung transplant (November 2017 to December 2024) with at least 6 months of follow-up were identified in the United Network for Organ Sharing registry and stratified by DM diagnosis at waitlist registration. CLAD was defined as ≥20% forced expiratory volume in 1 second and/or forced vital capacity decline after >3 months follow-up. Kaplan-Meier and multivariable Cox models assessed survival and CLAD risk, with subgroup analysis by race and ethnicity. RESULTS: Among 18,199 analyzed patients, 3479 (18.3%) had DM. CLAD rates were higher among recipients with DM (21.3% vs 17.4%, P = .003). Grade 3 primary graft dysfunction at 72 hours was more frequent among recipients with DM (20.3% vs 17.1%, P = .03). Additionally, 5-year overall survival was lower in DM patients (55.2% vs 58.7%, P = .003). On multivariate analysis, DM was associated with increased risk of 5-year mortality (hazard ratio, 2.58, P = .004) and CLAD (odds ratio, 1.46, P = .03). Notably, in patients with DM, 5-year survival was significantly decreased among Asian patients (P = .024) compared with other races. Among patients with DM, Asian status was independently associated with increased risk of mortality (hazard ratio, 1.72, P = .002). CONCLUSIONS: Recipient DM is associated with reduced long-term survival and CLAD risk after lung transplant. Asian American recipients with DM appear to face disproportionately worse survival, suggesting a potential interaction between race, ethnicity, and metabolic status.