Abstract / Summary
Abstract Background Diabetes contributes substantially to long-term morbidity after solid-organ transplantation, but comparisons of kidney function and glycemic control between pretransplant diabetes mellitus (PDM) and post-transplant diabetes mellitus (PTDM) remain limited. Methods This single-center retrospective cross-sectional study included 113 solid-organ transplant recipients with diabetes evaluated between May 2017 and May 2026. Kidney function, glycemic control, albuminuria, and treatment patterns were assessed. The primary analysis compared PDM with PTDM; comparisons of early- versus late-onset PTDM and sodium-glucose cotransporter 2 (SGLT2) inhibitor users versus non-users were exploratory. Multivariable linear regression models evaluated estimated glomerular filtration rate (eGFR), urinary albumin-to-creatinine ratio (UACR), and glycated hemoglobin (HbA1c), with adjustment for clinical and treatment variables. Results The cohort included liver (51.3%), kidney (36.3%), and heart (12.4%) transplant recipients; 61.6% had PTDM. Mean time since transplantation was 10.73 ± 7.60 years, mean eGFR was 60.77 ± 28.39 mL/min/1.73 m², and mean HbA1c was 7.40 ± 1.84%; 53.2% had HbA1c > 7%. Compared with PTDM, patients with PDM were older (62.37 ± 10.71 vs. 57.80 ± 11.76 years; P = 0.041), had shorter time since transplantation (6.98 ± 5.78 vs. 13.07 ± 7.69 years; P < 0.001), and lower eGFR (53.06 ± 21.82 vs. 65.78 ± 31.02 mL/min/1.73 m²; P = 0.024), while glycemic control was similar. After multivariable adjustment, the eGFR difference was no longer significant (adjusted difference 8.6 mL/min/1.73 m² higher in PTDM; 95% CI − 3.8 to 21.0; P = 0.170). Albuminuria (UACR ≥ 30 mg/g) was present in 45.9% of 98 patients with available measurements. Median UACR was higher in PTDM than PDM (28.1 vs. 19.5 mg/g; P = 0.037), and LDL cholesterol was independently associated with UACR (β = 0.072 log10 mg/g per 10 mg/dL; 95% CI 0.031–0.113; P < 0.001). Early- and late-onset PTDM had similar kidney function and glycemic control; SGLT2 inhibitor comparisons were nonsignificant after multiplicity adjustment. Only 40% of patients with albuminuria were receiving an SGLT2 inhibitor. Conclusions Long-term solid-organ transplant recipients with diabetes showed substantial kidney dysfunction and suboptimal glycemic control. Kidney dysfunction was frequently non-albuminuric, whereas albuminuria identified a distinct high-risk subgroup with limited use of cardiorenal-protective therapy. Prospective studies are needed to define longitudinal outcomes and the role of newer glucose-lowering therapies.