Early Post-Transplant Glycemic Variability and Its Association with Post-Transplant Dysglycemia After Kidney Transplantation

Background: Glycemic variability (GV) may play an important role in metabolic outcomes after kidney transplantation (KT). This study aimed to evaluate the association between early post-transplant GV, assessed by continuous glucose monitoring (CGM), and the subsequent development of post-transplant dysglycemia. Methods: This prospective exploratory pilot study included adult recipients of primary deceased-donor KT at Martin University Hospital, Slovakia. The Dexcom G6 CGM system was applied immediately before KT and continuously measured interstitial glucose for seven days after KT. Demographic, clinical, and biochemical data were collected on day 0, and 7, and at months 3, 12. Results: Twenty patients completed the 12-month follow-up. PTDM/prediabetes developed in 10 (50%) and had higher HbA1c on day 7 (p = 0.038) and lower postprandial insulin (p = 0.042). At 3 and 12 months, HbA1c (p = 0.006), fasting insulin (p = 0.0219), and HOMA-IR (p = 0.006) were significantly elevated in this group. CGM demonstrated higher mean glucose (p = 0.021), SD (p = 0.001), and estimated HbA1c (p = 0.017), with longer time above range (p = 0.042) and shorter time in range (p = 0.037). In exploratory regression analyses, CV ≥ 36% (aOR 7.31, p = 0.049) and TAR (aOR 1.35, p = 0.045) were associated with subsequent PTDM/prediabetes. Conclusions: In this prospective exploratory pilot study, higher early postoperative GV was associated with subsequent post-transplant dysglycemia. These findings suggest that CGM-derived metrics may help identify patients at higher metabolic risk after KT; however, given the small sample size and exploratory design, the results should be interpreted as hypothesis-generating.