Table 1.
Characteristics of the studied cohorts
| Medical population | Surgical population | |||||||
|---|---|---|---|---|---|---|---|---|
| Total n = 1,339 |
≤6.6 mmol/L n = 268 |
'Safe range' n = 804 |
≥8.5 mmol/L n = 267 |
Total n = 4,489 |
≤6.9 mmol/L n = 898 |
'Safe range' n = 2,694 |
≥9.5 mmol/L n = 897 |
|
| Age in years, mean ± SD | 61.8 ± 16.9 | 59.0 ± 18.4 | 62.5 ± 16.2 | 62.4 ± 17.0 | 66.0 ± 12.0 | 66.8 ± 12.5 | 65.4 ± 12.1 | 67.2 ± 11.3 |
| Female gender, percentage | 38.2 | 37.3 | 37.7 | 40.4 | 33.2 | 36.6 | 32.0 | 33.4 |
| APACHE II score, mean ± SD | 24.6 ± 8.8 | 24.8 ± 9.1 | 24.1 ± 8.1 | 25.8 ± 10.2 | 15.1 ± 4.6 | 16.3 ± 5.2 | 14.8 ± 4.5 | 14.7 ± 4.2 |
| Diabetes mellitus, percentage | 0.6 | 0.4 | 0.5 | 1.1 | 15.4 | 23.7 | 16.4 | 4.1 |
| Died in the ICU, percentage | 20.9 | 26.9 | 14.1 | 35.6 | 1.6 | 3.6 | 1.0 | 1.4 |
| Died in the hospital, percentage | 31.3 | 35.4 | 26.6 | 41.2 | 4.3 | 7.5 | 3.9 | 2.7 |
| Morning glucose in mmol/L, mean ± SD | 7.4 ± 2.6 | 5.9 ± 1.0 | 7.1 ± 1.2 | 10.3 ± 4.5 | 7.7 ± 2.3 | 5.8 ± 1.2 | 7.3 ± 1.7 | 10.6 ± 1.9 |
| Overall glucose in mmol/L, mean ± SD | 7.9 ± 2.7 | 6.0 ± 0.6 | 7.3 ± 0.5 | 11.6 ± 4.1 | 8.1 ± 1.6 | 6.4 ± 0.5 | 7.9 ± 0.7 | 10.7 ± 1.1 |
| Hypoglycemia incidence, percentage | 9.9 | 18.7 | 8.8 | 4.5 | 1.8 | 4.8 | 1.3 | 0.1 |
| SD, median (IQR) | 2.0 (1.5-2.9) | 1.6 (1.2-1.9) | 2.0 (1.6-2.6) | 3.8 (2.7-5.4) | 1.8 (1.3-2.3) | 1.6 (1.3-2.0) | 1.8 (1.4-2.4) | 1.9 (1.4-2.6) |
| MAG change, median (IQR) | 0.8 (0.5-1.1) | 0.5 (0.3-0.8) | 0.8 (0.6-1.0) | 1.4 (0.9-2.0) | 0.6 (0.4-0.8) | 0.5 (0.4-0.7) | 0.6 (0.4-0.9) | 0.5 (0.3-0.7) |
| Caloric intake per 24 hours, mean ± SD | 1,103.0 ± 758.4 | 1,159.3 ± 1,108.6 | 1,107.1 ± 507.2 | 1,033.6 ± 944.5 | 315.0 ± 392.3 | 427.7 ± 466.6 | 322.8 ± 387.5 | 181.5 ± 268.9 |
| Use of insulin, percentage | 88.5 | 79.5 | 93.3 | 82.8 | 64.0 | 93.1 | 71.8 | 11.6 |
| Insulin dose in IU/hour, median (IQR) | 1.4 (0.8-2.4) | 0.6 (0.4-1.0) | 1.4 (0.9-2.1) | 3.4 (2.0-6.2) | 1.2 (0.7-1.9) | 1.0 (0.7-1.5) | 1.3 (0.8-2.0) | 1.5 (0.7-3.2) |
| Use of vasopressor drugs, percentage | 86.0 | 19.4 | 11.8 | 15.4 | 94.8 | 94.1 | 94.2 | 97.0 |
| Use of corticoids, percentage | 92.5 | 91.0 | 94.8 | 86.9 | 99.1 | 99.0 | 99.1 | 99.1 |
| Mechanical ventilation, percentage | 81.6 | 81.7 | 85.0 | 71.2 | 97.9 | 97.3 | 97.9 | 98.6 |
| CVVH, percentage | 16.7 | 20.1 | 17.4 | 11.2 | 2.6 | 7.0 | 1.8 | 0.8 |
Characteristics of the studied cohorts are divided by mean glucose ranges. The 'safe range' refers to the mean glucose levels associated with the lowest mortality rates: 6.7 to 8.4 mmol/L in the medical cohort and 7.0 to 9.4 mmol/L in the surgical cohort. Hypoglycemia was defined as at least one glucose value of not more than 2.2 mmol/L. APACHE II, Acute Physiology and Chronic Health Evaluation II; CVVH, continuous veno-venous hemofiltration; ICU, intensive care unit; IQR, interquartile range; MAG, mean absolute glucose; SD, standard deviation.