Diabetes Technol Ther. 2026 Sep 29.
15209156261492040
INNODIA consortium C Mathieu, P Gillard, K Casteels, L Overbergh, D Dunger, C Wallace, M Evans, A Thankamony, E Hendriks, S Bruggraber, ML Marcovecchio, M Peakman, N Morgan, S Richardson, J Todd, L Wicker, A Mander, C Dayan, M Alhadj Ali, T Pieber, D Eizirik, M Cnop, S Brunak, F Pociot, J Johannesen, P Rossing, Quigley C Legido, R Mallone, R Scharfmann, C Boitard, M Knip, T Otonkoski, R Veijola, R Lahesmaa, M Oresic, J Toppari, T Danne, AG Ziegler, P Achenbach, T Rodriguez-Calvo, M Solimena, E Bonifacio, S Speier, R Holl, F Dotta, F Chiarelli, P Marchetti, E Bosi, S Cianfarani, P Ciampalini, C de Beaufort, K Dahl-Jørgensen, T Skrivarhaug, G Joner, L Krogvold, P Jarosz-Chobot, T Battelino, D Smigoc Schweiger, B Thorens, M Gotthardt, B Roep, T Nikolic, A Zaldumbide, A Lernmark, M Lundgren, G Costeca, T Strube, A Schulte, A Nitsche, M Peakman, J Vela, M von Herrath, J Wesley, A Napolitano-Rosen, M Thomas, N Schloot, A Goldfine, F Waldron-Lynch, J Kompa, A Vedala, N Hartmann, G Nicolas, J van Rampelbergh, N Bovy, S Dutta, J Soderberg, S Ahmed, F Martin, E Latres, G Agiostratidou, A Koralova
INTRODUCTION: Continuous glucose monitoring (CGM) can characterize subtle glucose changes in early-stage type 1 diabetes (T1D). We assessed whether CGM metrics predict Stage 3 T1D in first-degree relatives (FDRs) with positive islet autoantibodies (IAbs) and dysglycemia participating in INNODIA.
METHODS: We analyzed IAb-positive FDRs with dysglycemia and available CGM data. CGM metrics were analyzed longitudinally and in a restricted analysis limited to the last assessment before Stage 3 T1D in progressors. CGM metrics were compared using linear mixed models. Predictive performance of single and combined CGM metric models was evaluated using receiver operating characteristic curve analyses.
RESULTS: Data from 27 participants (14 females [52%], median [interquartile range] age: 16.8 [11.9-39.8] years) were analyzed. Nine participants progressed to Stage 3 T1D after a median of 163 [129-244] days from CGM assessment. In the restricted analysis, progressors had higher mean glucose (132 vs. 111 mg/dL, P = 0.001), time >140 mg/dL (36% vs. 10%, P = 0.003), and time >180 mg/dL between 9 PM and 2 AM (8.1% vs. 1.0%, P = 0.005), whereas time <70 mg/dL between 4 and 7 AM was lower (0% vs. 1.2%, P = 0.001). Time >140 mg/dL yielded an area under the curve (AUC) of 0.83 (95% confidence interval [CI] 0.66-1.00). Combining time >140 mg/dL with time-specific percentages >180 and <70 mg/dL increased AUC to 0.93 (95% CI 0.84-1.00). A model incorporating time between 70 and 140 mg/dL, mean glucose, early morning <70 mg/dL, and MAGE achieved 100% sensitivity and 86% specificity.
CONCLUSIONS: CGM may help identify FDRs with IAbs and dysglycemia at higher risk of progressing to Stage 3 T1D. Combining CGM metrics improved prediction compared with time >140 mg/dL alone.
Keywords: continuous glucose monitoring; dysglycemia; early stage; first-degree relatives; islet autoantibodies; prediction; type 1 diabetes