Endocrine Abstracts

JOINT1394

Background: Evidence of diabetic nephropathy (DN) following heart transplantation (HTx) in Asian populations remains scarce. This study aimed to assess the incidence, risk factors of post-HTx DN and evaluate its impact on patient survival.

Methods: A retrospective cohort study was conducted on consecutive adult patients who underwent their first HTx at a single center between 2019 and 2023 and survived to hospital discharge. These patients were prospectively followed until December 31, 2024. Post-HTx DN was defined as the concurrent presence of new-onset diabetes mellitus (demonstrated by ≥2 consecutive HbA1c ≥6.5% or fasting plasma glucose ≥126 mg/dL) and albuminuria (urine albumin-to-creatinine ratio ≥30 mg/g) in patients without pre-existing diabetes, assessed from three months after heart transplantation onward. Patient survival was assessed using the Kaplan-Meier method, with group comparisons performed using the log-rank test. Cox proportional hazards models were employed for multivariate analysis. Statistical analyses were conducted using STATA version 16 (StataCorp, Texas, USA).

Results: Among 52 patients (85% male, mean age 47.2±11.8 years, mean BMI 21.7±3.3 kg/m²), 10 (19%) had pre-existing diabetes mellitus (DM) before HTx. During a median follow-up of 36 months, 11 patients (21%) developed post-HTx DM, with 2 (4%) progressing to DN. Among patients without pre-existing DM before HTX, new-onset post-HTx DN showed no significant associations with patient characteristics, choice of immunosuppressant regimens, or the occurrence of at least one episode of grade ≥2R allograft rejection requiring steroid pulse therapy. Post-HTx DN was independently associated with a sustained decline in kidney function (hazard ratio [HR] 17.4, P = 0.001), defined by the persistence of one of the following criteria for at least 4 weeks: ≥ 40% decline in eGFR, eGFR < 15 ml/min/1.73 m², doubling of serum creatinine, or initiation of dialysis. During the follow-up period, four deaths were recorded, with causes including hemorrhagic stroke, cardiac arrest, sepsis with multiple organ failure, and an unknown cause. Both post-HTx DN (HR, 47.3; P = 0.007) and post-HTx dialysis (HR, 45.4; P = 0.002) were identified as significant independent risk predictors of all-cause mortality.

Conclusions: Approximately 4% of HTx patients developed post-HTx DN, which may serve as one of the prognostic indicators for their survival outcomes. Further studies on a larger sample size are needed to identify risk predictor of post-HTx DN, enabling the implementation of effective preventive measures.