Table 3.
Continuous Glucose Monitor Metrics During Closed-Loop Mode System Use—By Pump (N = 41 Subjects)
| Time of the day | Overall | Daytime | Nighttime | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Pump | Pooled (N = 41) | Pump 1 (N = 17) | Pump 2 (N = 24) | Pooled (N = 41) | Pump 1 (N = 17) | Pump 2 (N = 24) | Pooled (N = 41) | Pump 1 (N = 17) | Pump 2 (N = 24) |
| Hours of sensor readings, median (IQR) | 258 (207, 314) | 317 (292, 338) | 215 (166, 255) | 185 (145, 218) | 220 (206, 240) | 162 (127, 184) | 72 (53, 90) | 99 (83, 108) | 63 (42, 78) |
| Nadir (mg/dL), median (IQR) | 44 (40, 54) | 43 (40, 53) | 45 (40, 55) | 44 (40, 54) | 44 (40, 53) | 45 (40, 55) | 63 (55, 70) | 59 (43, 70) | 66 (58, 69) |
| % <50 mg/dL, median (IQR) | 0.1% (0.0%, 0.3%) | 0.1% (0.0%, 0.5%) | 0.1% (0.0%, 0.3%) | 0.2% (0.0%, 0.4%) | 0.1% (0.0%, 0.4%) | 0.2% (0.0%, 0.4%) | 0.0% (0.0%, 0.0%) | 0.0% (0.0%, 0.1%) | 0.0% (0.0%, 0.0%) |
| % <60 mg/dL, median (IQR) | 0.6% (0.2%, 1.2%) | 0.5% (0.2%, 1.3%) | 0.6% (0.2%, 1.0%) | 0.6% (0.2%, 1.6%) | 0.6% (0.2%, 1.7%) | 0.6% (0.2%, 1.4%) | 0.0% (0.0%, 0.4%) | 0.1% (0.0%, 0.5%) | 0.0% (0.0%, 0.3%) |
| % <70 mg/dL, median (IQR) | 1.7% (0.8%, 2.5%) | 1.8% (0.6%, 2.5%) | 1.7% (1.0%, 2.5%) | 1.9% (0.8%, 3.2%) | 2.0% (0.7%, 2.9%) | 1.8% (1.0%, 3.4%) | 0.5% (0.0%, 1.5%) | 0.7% (0.0%, 1.5%) | 0.5% (0.1%, 1.5%) |
| Low BG index, median (IQR) | 0.5 (0.3, 0.8) | 0.5 (0.3, 0.8) | 0.5 (0.3, 0.8) | 0.6 (0.3, 0.9) | 0.6 (0.3, 0.9) | 0.6 (0.3, 0.9) | 0.3 (0.2, 0.6) | 0.3 (0.2, 0.6) | 0.4 (0.2, 0.6) |
| Mean glucose (mg/dL), mean ± SD | 152 ± 17 | 154 ± 16 | 151 ± 18 | 154 ± 19 | 156 ± 20 | 153 ± 18 | 150 ± 21 | 150 ± 13 | 149 ± 25 |
| Coefficient of variation, median (IQR) | 32% (30%, 36%) | 34% (31%, 36%) | 32% (30%, 37%) | 34% (30%, 37%) | 35% (30%, 37%) | 34% (31%, 37%) | 29% (26%, 32%) | 29% (26%, 31%) | 29% (25%, 34%) |
| Standard deviation (mg/dL), median (IQR) | 48 (42, 56) | 52 (45, 58) | 48 (42, 55) | 51 (44, 59) | 53 (45, 62) | 48 (44, 56) | 41 (37, 51) | 43 (38, 50) | 40 (35, 55) |
| % In range 70–180 mg/dL, mean ± SD | 73 ± 10% | 71 ± 10% | 73 ± 10% | 70 ± 11% | 69 ± 13% | 71 ± 10% | 76 ± 16% | 77 ± 9% | 76 ± 19% |
| % In range 70–140 mg/dL, mean ± SD | 47 ± 11% | 44 ± 10% | 48 ± 11% | 44 ± 11% | 43 ± 12% | 45 ± 11% | 51 ± 16% | 47 ± 13% | 53 ± 18% |
| High BG index, median (IQR) | 5.1 (3.8, 7.3) | 5.8 (4.4, 6.8) | 4.8 (3.6, 7.4) | 5.7 (4.1, 7.8) | 6.4 (4.9, 7.8) | 5.7 (3.9, 7.5) | 4.0 (2.9, 6.4) | 4.0 (3.8, 6.2) | 4.1 (2.5, 6.5) |
| % >180 mg/dL, median (IQR) | 26% (18%, 32%) | 28% (20%, 32%) | 23% (17%, 33%) | 27% (20%, 36%) | 29% (22%, 36%) | 27% (17%, 34%) | 18% (13%, 31%) | 20% (15%, 31%) | 17% (10%, 31%) |
| % >250 mg/dL, median (IQR) | 4% (2%, 7%) | 5% (3%, 8%) | 3% (2%, 7%) | 4% (1%, 10%) | 6% (3%, 11%) | 3% (1%, 7%) | 2% (0%, 6%) | 2% (1%, 5%) | 2% (0%, 7%) |
| % >300 mg/dL, median (IQR) | 0.6% (0.1%, 2.1%) | 1.2% (0.2%, 2.9%) | 0.5% (0.0%, 1.9%) | 0.8% (0.0%, 2.5%) | 1.6% (0.0%, 4.0%) | 0.7% (0.0%, 2.0%) | 0.0% (0.0%, 0.3%) | 0.1% (0.0%, 0.8%) | 0.0% (0.0%, 0.3%) |
BG, blood glucose.