Introduction & Objective: CGM metrics such as time in different target ranges and glucose management indicator (GMI) provide insight in glycemic control. In some people with diabetes (PWD) an o"set between A1c and GMI was observed. We investigated if offset and correspondence between A1c and GMI were stable over time.

Methods: Registry data from 113 PWD (84 T1D, 29 T2D) using Abbott Libre with at least 4 A1c values were included (age: 36.6(21.9; 54.5) ys, A1c 7.7(7.1; 8.4)%, GMI 7.4(6.8; 8.0)%, 46% women. CGM data of the 14-days prior to each A1c were used. We used A1c/GMI at baseline(BL), the 2 follow-ups(FU2, FU3) and the last available measurement(LT). The difference between A1c and GMI over time was assessed and is indicated as delta-GMI-A1c. An absolute delta >0.5% was considered relevant.

Results: 30.1%(n=34) had a stable relationship between GMI and A1c over time. Comparing trajectories between the three baseline groups, BL+(GMI>A1c, n=14/12.4%), BL=(GMI=A1c, n=60/53.1%) and BL-(GMI<A1c, n=39/34.5%), BL= has the largest portion of stable relationship (n=20/33.3%) vs. BL-(n=11/28.2%) vs. BL+(n=3/21.4%). 8.8%(n=8) switched to stable correspondence after baseline (8/20.5%(BL-);2/14.3%(BL+)).

Conclusion: A1c and GMI vary between individuals and baseline groups, with 30% having a stable relationship over time. Our data support using CGM to assess glycemia and highlight the need on the association of CGM on long-term outcome.

Disclosure

J.K. Mader: Advisory Panel; Becton, Dickinson and Company. Speaker's Bureau; Becton, Dickinson and Company, A. Menarini Diagnostics, Boehringer-Ingelheim, diaTribe. Other Relationship; Diabetes UK. Stock/Shareholder; decide Clinical Software GmbH. Advisory Panel; embecta. Speaker's Bureau; embecta, Viatris Inc., Eli Lilly and Company. Advisory Panel; Eli Lilly and Company, Medtronic. Speaker's Bureau; Medtrust. Advisory Panel; Novo Nordisk A/S. Speaker's Bureau; Novo Nordisk A/S. Advisory Panel; PharmaSens, Roche Diabetes Care. Speaker's Bureau; Roche Diabetes Care. Board Member; Sanofi-Aventis Deutschland GmbH. Speaker's Bureau; Sanofi-Aventis Deutschland GmbH, Sanofi, Dexcom, Inc., Viatris Inc. Advisory Panel; Viatris Inc. Speaker's Bureau; Ypsomed AG. Research Support; European Union. Stock/Shareholder; elyte Diagnostics GmbH. Other Relationship; elyte Diagnostics GmbH. Board Member; European Association for the Study of Diabetes. Research Support; European Union Aviation Safety Agency. P.M. Baumann: None. M. Cigler: None. T. Poettler: None. M. Oberosler: None. J. Gruber: None. S. Kheir: None. C. Harer: Other Relationship; Novo Nordisk, Eli Lilly and Company, Viatris Inc., Kelcon GmbH. R. Meçani: None. H. Sourij: Advisory Panel; Amarin Corporation. Speaker's Bureau; Amgen Inc., Amarin Corporation, Bayer Inc. Advisory Panel; Boehringer-Ingelheim. Speaker's Bureau; Boehringer-Ingelheim. Research Support; Boehringer-Ingelheim. Advisory Panel; Eli Lilly and Company. Research Support; Eli Lilly and Company. Speaker's Bureau; Eli Lilly and Company. Advisory Panel; Novartis AG. Speaker's Bureau; Novartis AG. Advisory Panel; Novo Nordisk. Research Support; Novo Nordisk. Speaker's Bureau; Novo Nordisk. Research Support; Sanofi. Speaker's Bureau; Sanofi. Consultant; K:Businesscom.

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