Glycemic control and kidney function in pretransplant versus post-transplant diabetes mellitus among solid-organ transplant recipients: a single-center cross-sectional study

<title>Abstract</title> <p>Background Diabetes contributes substantially to long-term morbidity after solid-organ transplantation. However, direct comparisons of kidney function and glycemic control between pretransplant diabetes mellitus (PDM) and post-transplant diabetes mellitus (PTDM), particularly in cohorts with prolonged follow-up and a predominance of non-kidney transplant recipients, remain limited. Methods This single-center, retrospective, cross-sectional study included 119 adult solid-organ transplant recipients with diabetes followed between July 2023 and October 2025. Kidney function, glycemic control, and treatment patterns were compared between PDM and PTDM, early- and late-onset PTDM, and sodium-glucose cotransporter 2 inhibitor users and non-users. Multivariable logistic regression evaluated factors independently associated with PTDM. Results The cohort included liver (52.1%), kidney (35.3%), and heart (12.6%) transplant recipients. Most patients had PTDM (62.2%). Mean time since transplantation was 13.97 ± 7.59 years, mean estimated glomerular filtration rate (eGFR) was 60.46 ± 28.79 mL/min/1.73 m², and mean glycated hemoglobin was 7.37 ± 1.82%; 52.9% of patients had an HbA1c level &gt; 7%. Compared with patients with PTDM, those with PDM were older (64.77 ± 10.50 vs. 59.66 ± 12.16 years; P = 0.031), had a shorter time since transplantation (10.51 ± 6.46 vs. 16.27 ± 7.44 years; P &lt; 0.001), and had lower eGFR (52.15 ± 22.54 vs. 65.33 ± 30.83 mL/min/1.73 m²; P = 0.017), whereas glycemic control was similar. In multivariable analysis, age and time since transplantation remained independently associated with PTDM, whereas eGFR was not independently associated with diabetes group (adjusted odds ratio 1.018 per 1 mL/min/1.73 m² increase, 95% confidence interval 0.995–1.042; P = 0.133). Early - and late-onset PTDM had comparable kidney function and glycemic control. Sodium-glucose cotransporter 2 inhibitor users were older and more frequently had eGFR categories G3-G5. Conclusions Long-term solid-organ transplant recipients with diabetes had a substantial burden of kidney dysfunction and suboptimal glycemic control. Prospective studies are needed to clarify longitudinal cardiorenal outcomes and the role of newer glucose-lowering therapies.</p>