Table 2.
Comparison of Continuous Glucose Monitoring Metrics and HbA1c Levels with Neonatal Hypoglycemia and Large for Gestational Age
| CGM metrics and HbA1c | Total n = 41 | Neonatal hypoglycemia n = 21 (51%) | No neonatal hypoglycemia n = 20 (49%) | P | LGA n = 23 (56%) | No LGA n = 18 (44%) | P |
|---|---|---|---|---|---|---|---|
| Early pregnancy metrics | |||||||
| TIR, % | 65 (24) | 58 (23) | 73 (23) | 0.05 | 57 (27) | 75 (16) | 0.02 |
| TAR, % | 31 (26) | 39 (25) | 21 (24) | 0.03 | 40 (29) | 19 (17) | 0.01 |
| TBR, % | 4 (6) | 3 (4) | 6 (9) | 0.28 | 3 (3) | 6 (9) | 0.16 |
| Average glucose, mmol/L | 7.0 (1.9) | 7.6 (1.9) | 6.3 (1.6) | 0.03 | 7.6 (2.1) | 6.2 (1.2) | 0.01 |
| GMI, % | 6.1 (5.7, 6.5) | 6.3 (5.9, 6.6) | 5.8 (5.4, 6.3) | 0.04 | 6.3 (5.9, 6.6) | 5.8 (5.5, 6.3) | 0.09 |
| SD, mmol/L | 1.9 (0.6) | 2.1 (0.5) | 1.6 (0.6) | 0.01 | 2.0 (0.4) | 1.8 (0.7) | 0.19 |
| CV% | 28 (6.9) | 30 (7) | 27 (7) | 0.15 | 28 (6.4) | 28 (7.8) | 0.94 |
| IQR | 2.3 (0.6) | 2.8 (0.5) | 1.9 (0.6) | 0.001 | 2.7 (0.5) | 2.0 (0.6) | 0.006 |
| Early HbA1c, % | 7.8 (6.5, 8.6) | 8.1 (7.6, 8.9) | 6.4 (5.7, 6.9) | 0.001 | 7.7 (6.8, 8.8) | 7.0 (5.5, 8.3) | 0.17 |
| Early glycemic targets | |||||||
| TIR >70%, n (%) | 19 (50%) | 6 (30%) | 13 (72%) | 0.009 | 9 (43%) | 10 (59%) | 0.32 |
| TAR <25% n (%) | 21 (55%) | 7 (35%) | 14 (78%) | 0.008 | 9 (43%) | 12 (71%) | 0.08 |
| TBR <4%, n (%) | 22 (59%) | 12 (60%) | 10 (59%) | 0.94 | 13 (62%) | 9 (56%) | 0.72 |
| CV <36%, n (%) | 30 (81%) | 16 (80%) | 14 (82%) | 0.85 | 18 (86%) | 12 (75%) | 0.41 |
| GMI <6.5, n (%) | 26 (79%) | 14 (74%) | 12 (86%) | 0.40 | 14 (74%) | 12 (86%) | 0.40 |
| Early HbA1c <6.5%, n (%) | 10 (26%) | 0 | 10 (56%) | 0.000 | 4 (18%) | 6 (38%) | 0.18 |
| Late pregnancy metrics | |||||||
| TIR, % | 68 (21) | 60 (19) | 77 (19) | 0.007 | 65 (18) | 72 (25) | 0.32 |
| TAR, % | 26 (22) | 34 (20) | 15 (20) | 0.007 | 30 (19) | 20 (25) | 0.17 |
| TBR, % | 6 (6) | 6 (7) | 7 (7) | 0.68 | 5 (5) | 8 (8) | 0.20 |
| Average glucose, mmol/L | 6.5 (1.4) | 6.9 (1.3) | 5.9 (1.3) | 0.01 | 6.8 (1.3) | 6.0 (1.3) | 0.09 |
| GMI, % | 6.1 (5.7, 6.3) | 6.2 (6.0, 6.4) | 5.7 (5.5, 6.2) | 0.02 | 6.2 (5.7, 6.4) | 5.8 (5.5, 6.3) | 0.05 |
| SD, mmol/L | 1.9 (0.6) | 2.2 (0.5) | 1.7 (0.6) | 0.005 | 2.1 (0.5) | 1.7 (0.6) | 0.04 |
| CV% | 30 (6.2) | 32 (6) | 28 (6) | 0.03 | 32 (5.1) | 28 (7.0) | 0.22 |
| IQR, mmol/L | 2.7 (1.0) | 3.2 (0.9) | 2.2 (0.7) | 0.001 | 3.0 (0.9) | 2.3 (0.9) | 0.03 |
| Third trimester HbA1c, % | 6.8 (6.1, 7.4) | 6.9 (6.3, 8.1) | 6.3 (5.8, 7.1) | 0.04 | 6.8 (6.5, 7.7) | 6.1 (5.8, 7.1) | 0.05 |
| Late glycemic targets | |||||||
| TIR >70%, n (%) | 24 (59%) | 7 (33%) | 17 (85%) | 0.001 | 12 (52%) | 12 (67%) | 0.35 |
| TAR <25%, n (%) | 24 (60%) | 8 (38%) | 16 (84%) | 0.003 | 11 (48%) | 13(76%) | 0.07 |
| TBR <4%, n (%) | 18 (44%) | 11 (52%) | 7 (35%) | 0.26 | 11 (48%) | 7 (38%) | 0.56 |
| CV <36%, n (%) | 31 (76%) | 13 (62%) | 18 (90%) | 0.03 | 17 (74%) | 14 (78%) | 0.77 |
| GMI <6.1, n (%) | 17 (50%) | 5 (28%) | 12 (75%) | 0.006 | 7 (35%) | 10 (71%) | 0.03 |
| GMI <6.5, n (%) | 28 (85%) | 15 (83%) | 13 (87%) | 0.79 | 16 (80%) | 12 (90%) | 0.33 |
| Third trimester HbA1c <6.1%, n (%) | 8 (23%) | 1 (6%) | 7 (39%) | 0.02 | 1 (6%) | 7 (41%) | 0.01 |
Data are presented as mean (SD) or median (IQR) or n (%); total n is less for the following characteristics: Early HbA1c n = 38, third trimester HbA1c n = 35. Early metrics, first 2 weeks of sensor use, mean (range) gestation 16 (6–28) weeks. Late metrics, last 2 weeks of sensor use, mean (range) gestation 35 (28–38) weeks. Early HbA1c, first or second trimester HbA1c, mean (SD) gestation 9.6 (6) weeks. Range defined as glucose 3.5–7.8 mmol/L (63–140 mg/dL) and TIR/TAR/TBR expressed as a percentage of all time CGM is active over a 14-day period.
CV, coefficient of variation; GMI, glucose management indicator; TAR, time above range; TBR, time below range; TIR, time in range.