Table 2.
Impact of CGM switching from Freestyle Libre1 to Dexcom G4 platinum over 12 months on glucose metrics.
| Variables | FSL1 M0 | DG4 M3 | DG4 M6 | DG4 M12 | P M3 vs. M0 |
P M6 vs. M0 |
P M12 vs. M0 |
|---|---|---|---|---|---|---|---|
| GMI 1, % | 7.98 ± 1.34 | 7.60 ± 1.08 * | 7.45 ± 1.14 * | 7.97 ± 1.15 | 0.0255 | 0.0099 | NS |
| TIR 70–180 mg/dL 1,2, % | 45.4 ± 16.0 | 53.3 ± 16.4 * | 54.8 ± 16.0 * | 50.2 ± 17.1 | 0.0003 | <0.0001 | 0.0365 |
| TBR < 70 mg/dL 1,2, % | 7.0 [4.5;12.5] | 4.6 [2.6;9.9] * | 4.6 [4.6;8.8] * | 2.5 [1.6;5.5] | 0.0153 | 0.0450 | 0.0007 |
| TBR < 54 mg/dL 1,2, % | 2.3 [0.8;7.0] | 1.3 [0.7;4.3] * | 1.4 [0.5;2.7] | 0.7 [0.4;0.8] | 0.0441 | 0.0107 | 0.0073 |
| TAR > 180 mg/dL 1,2, % | 45.4 ± 19.3 | 41.0 ± 17.8 * | 39.0 ± 18.0 * | 45.9 ± 18.2 | NS | 0.0152 | NS |
| TAR > 250 mg/dL 1,2, % | 19.4 [9.3;32.2] | 10.1 [5.8;21.5] * | 10.1 [3.6;25.7] * | 16.2 [8.7;30.5] | 0.0127 | 0.0071 | NS |
| Average IG 1, mg/dL | 184.5 ± 46.2 | 171.7 ± 31.0 * | 166.9 ± 32.7 * | 182.0 ± 33.1 | 0.0433 | 0.0206 | NS |
| CV 1, % | 45.4 ± 8.3 | 40.0 ± 6.0 | 39.7 ± 6.3 | 39.1 ± 5.1 | 0.0032 | 0.0013 | 0.0009 |
| Sensor use rate, % | 78.0 [35.5;91.0] | 90.7 [66.1;94.5] | 82.0 [57.1;95.0] | 84.6 [57.1;92.2] | NS | NS | NS |
Data are expressed as mean ± standard deviation or median [Q1;Q3] from 21 T1D patients switching from FSL1 (M0) to DG4 followed-up at 3 months (M3), at 6 months (M6) and at 12 months (M12, endpoint). 1 Data represent average values calculated from the data collected on the ambulatory glucose profile report over 3 months (for M0 during the last 3 months of FSL1 use, for M3 during the first 3 months of DG4 use, and during the last 3 months of DG4 use for M6 and M12). 2 Data are expressed as percent of time over a 3 month-period. * Values significantly different compared to M12 considering only the period of DG4 use (paired student t-test two-tailed when Gaussian, or Wilcoxon matched-pairs signed rank test two-tailed when not gaussian; p < 0.05 significant; NS: not significant).Abbreviations: CGM, continuous glucose monitoring; %CV, glucose % coefficient of variation; DG4, Dexcom G4 platinum; FSL1, FreeStyle Libre version 1; GMI, glucose management indicator; HbA1c, plasma glycated hemoglobin A1c; IG, interstitial glucose; TAR, time-above-range; TBR, time-below-range; TIR, time-in-range.