Mini-Oral Presentation

Predictive value of early continuous glucose monitoring–detected hyperglycaemia for post-transplant diabetes mellitus among non-diabetic kidney transplant recipients

Presenter

Abhilash Tirkey (IN)

Senior Resident · Department of Renal Transplant Surgery · Post Graduate Institute of Medical Education and Research · Chandigarh

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Authors

Belmin B J Winston Gysley¹, Ashish Sharma¹, Sarbpreet Singh¹, Jasmine Sethi²

Affiliations

¹ Post Graduate Institute of Medical Education and Research

² Post Graduate Institute of Medical Education and Research

Abstract

Introduction: Post-transplant diabetes mellitus (PTDM) is a common metabolic complication following solid organ transplantation. The reported incidence of PTDM ranges from 20% to 30%, among the renal transplant recipients. Only few studies in the literature had made attempts to predict the development of PTDM much earlier than its actual time of diagnosis. In this study we have used a continuous glucose monitoring(CGM) device (Libre freestyle - Abbott Pvt Ltd.) during the early post-transplant period (day 4 to day 14) and analysed its predictive value in picking out the patients who were destined to develop PTDM in course of time.
Aim and objectives : To explore the potential of CGM regarding the prediction of Post Transplant Diabetes Mellitus (PTDM) and impaired glucose tolerance (IGT) within 1 year of renal transplantation.
Materials and Methodology: A single institutional prospective observational study conducted among non-diabetic chronic kidney disease patients undergoing living and deceased donor renal allograft transplantation within Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh between 2024 January to 2024 December . The patients enrolled in the study were inserted a CGM device in the early period and its records were stored in our database. Then these patients were followed up regularly with OGTT and HbA1C. At 6 months follow up patients were categorized to PTDM, IGT and NGT Figure 1(a). Their early period CGM records were analysed using statistical tools for determining the predictive value of continues glucose monitoring in early pick up PTDM susceptiblity.

Figure 1(a) : shows the consort flow diagram of the patients included for the study, their exclusion criteria’s, study plan, follow up and analysis scheme. Figure 1(b) : Depicting the timeline of incidence of PTDM / IGT among the recipients

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Results: Out of 104 patients by the end of six months, 32 recipients (30.7%) developed PTDM, 38 recipients (36.5%) developed IGT, and 34 recipients maintained normal glucose tolerance. The overall incidence of PTDM was 17.3%. No graft loss or mortality was observed during the study period. Among recipients who developed PTDM, 43.75% reverted to normal glucose tolerance by six months and were off all glucose-lowering medications Figure 1(b).
Among the CGM parameters studied, TAR greater than 180 mg/dL was the strongest predictor of PTDM. TAR >180 mg/dL between postoperative days 6 and 12 showed good predictive accuracy, with area under the curve values ranging from 0.747 to 0.826 Table 1(b). Mean blood glucose also demonstrated good predictive performance, with threshold values between 176 and 191 mg/dL showing high specificity and positive predictive value for PTDM. In contrast, TAR >140 mg/dL was highly sensitive for identifying overall dysglycaemia but was less specific for predicting PTDM Table 1(c)

Table 1(a) : showing the post operative characteristics of the recipients who had post-transplant diabetes mellitus, Impaired glucose tolerance and normal glucose tolerance Table 1 (b) : Receiver operating characteristic (ROC) curve Table 1 (c) : Statistically indices for the various CMG Metrices.

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Importantly, CGM detected early dysglycaemia even in recipients without traditional clinical risk factors, suggesting that early postoperative hyperglycaemia reflected underlying metabolic susceptibility rather than a transient stress response.
Conclusion: Early postoperative continuous glucose monitoring was effective in identifying kidney transplant recipients at risk for developing PTDM and IGT. CGM-derived metrics, particularly TAR greater than 180 mg/dL and mean blood glucose, demonstrated good predictive value for PTDM within six months of transplantation. These findings support the use of CGM as a universal early screening tool rather than a selective approach limited to high-risk individuals. Incorporation of CGM into early post-transplant metabolic surveillance may enable timely risk stratification, closer monitoring, and early intervention, with the potential to improve long-term metabolic and graft outcomes.