The TrialNet Pathway to Prevention Study (PtP) has enhanced our understanding of the progression through the stages of T1D identifying individuals at early stages of disease for prevention trials. Individuals with multiple islet AAb and normal OGTT are considered to be at Stage 1 T1D, and those with abnormal OGTT are at Stage 2 T1D. Our aim was to determine whether subtle forms of dysglycemia provide new clues about disease progression (Stage 3). 94 relatives of T1D probands from PtP underwent a 7-day CGM assessment (Dexcom G4 Platinum Professional) Three groups of relatives were evaluated: 1) Relatives at Stage 2 T1D whose 5-year risk for T1D progression is ∼70% (n=33); 2), relatives at Stage 1 T1D whose 5-year risk for T1D progression is ∼ 35% (n=51); and relatives with negative confirmed AAb and normal OGTT (n=10) whose 5-year risk for progression is <1%. CGM variations occur in a significant number of subjects with Stage 1 T1D (Figure) with increased variation in CGM glucose values assessed by mean amplitude of glucose excursion (MAGE) in relatives (n= 4 Stage 0; 31 Stage 1; and 27 Stage 2) at Stage 1 and Stage 2 T1D compared to that of low risk relatives (P = 0.005). Interstitial glucose >140 mg/dL was higher in relatives at Stage 1 and Stage 2 T1D compared to low risk relatives (P = 0.02).

In conclusion, CGM metrics may be useful in identifying dysglycemia in at risk relatives with normal OGTT.

D.M. Wilson: Advisory Panel; Self; Tolerion, Inc. Research Support; Self; Beta Bionics, Dexcom, Inc., Medtronic. P. Nelson: None. D. Scheinker: Advisory Panel; Self; Carta Healthcare. S. Pietropaolo: None. M. Acevedo-Calado: None. M. Ebrahimi: None. A. Steck: None. J.L. Dunne: None. C. Greenbaum: Research Support; Self; Janssen Research & Development. M. Pietropaolo: None.


National Institutes of Health

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