TABLE 4.
Hospital-Acquired Pressure Injury: Multivariate Cox Proportional Hazards Model
| Risk factor | HAPI | M | (SD) | Q1 | Q3 | HR | 95% CI | p |
|---|---|---|---|---|---|---|---|---|
| Age (years) | Yes | 71.3 | (13.9) | 63 | 82 | 1.36 | [1.25, 1.45] | <.001 |
| No | 65.4 | (17.3) | 55 | 79 | ||||
| COPS2 (score)a | Yes | 78.8 | (57.5) | 30 | 115 | 1.10 | [1.04, 1.16] | <.001 |
| No | 48.5 | (47.6) | 10 | 73 | ||||
| LAPS2 (score)b | Yes | 93.3 | (50.2) | 55 | 129 | 1.38 | [1.28, 1.50] | <.001 |
| No | 59.5 | (39.6) | 23 | 86 | ||||
| Braden Scale (score)c | Yes | 15.4 | (3.2) | 13 | 18 | 0.63 | [0.59, 0.67] | <.001 |
| No | 18.7 | (2.9) | 17 | 21 | ||||
|
|
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| n | (%) | |||||||
|
|
||||||||
| Full code (yes) | Yes | 1369 | (82.4) | 0.89 | [0.78, 1.03] | .11 | ||
| No | 634,525 | (87.3) | ||||||
| Diabetes (yes) | Yes | 840 | (50.6) | 1.09 | [0.98, 1.20] | .11 | ||
| No | 269,867 | (37.1) | ||||||
| Stroke (yes) | Yes | 366 | (22.0) | 1.03 | [0.90, 1.18] | .65 | ||
| No | 89,139 | (12.3) | ||||||
| Gender (female) | Yes | 723 | (43.5) | 0.77 | [0.70, 0.85] | <.001 | ||
| No | 387,785 | (53.4) | ||||||
| Admission type | ||||||||
| ED/surgical (yes) | Yes | 807 | (48.6) | 1.07 | [0.90, 1.29] | .44 | ||
| No | 436,835 | (60.1) | ||||||
| Non-ED/surgical (yes) | Yes | 480 | (28.9) | 1.00d | − | |||
| No | 70,645 | (9.7) | ||||||
| ED/medical (yes) | Yes | 132 | (7.9) | 0.62 | [0.52, 0.74] | <.001 | ||
| No | 56,301 | (7.7) | ||||||
| Non-ED/medical (yes) | Yes | 242 | (14.6) | 0.88 | [0.71, 1.10] | .27 | ||
| No | 162,824 | (22.4) | ||||||
Note. n = 1,661 (HAPI = yes); n = 726,605 (HAPI = no). Five thousand iterations of bootstrapped permutated tests were applied to all χ2 and t HAPI and non-HAPI values, resulting in p < .001 for univariate comparisons. Model c-statistic = 0.76, R2 = .02, calibrated slope = 0.99. Hazard ratio reflects the impact of the respective variable on the risk for HAPI over time when there is change from Q1 to Q3. COPS2 = Comorbidity Point Score, Version 2; ED = emergency department; HAPI = hospital-acquired pressure injury; HR = hazard ratio; LAPS2 = Laboratory-Based Acute Physiology Score, Version 2; Q1 = 25th percentile; Q3 = 75th percentile.
COPS2 is a longitudinal score based on 12 months of patient data; the higher the score, the greater the mortality risk due to comorbid illness.
LAPS2 measures acute physiologic instability during the 72 hours preceding admission; the higher the score, the greater the mortality risk due to acute physiologic derangement.
The lowest score in the first 24 hours after admission was used; lower scores represent a higher risk for pressure injury.
Reference group for admission type.