Table III.
Univariate and multivariate risk factor analysis for further apnea after randomized study treatment
| Characteristics | No further apnea (n = 58) | Further apnea (n = 27) | Univariate risk factor analysis |
Multivariate risk factor analysis |
||||
|---|---|---|---|---|---|---|---|---|
| OR | 95% CI | P value | OR | 95% CI | P value | |||
| Age, corrected for gestational age <37 wk | ||||||||
| ≤8 wk:>8 wk | 45:13 | 21:6 | 1.01 | 0.33-3.02 | .98 | |||
| >8 wk | 1.00 | Reference | ||||||
| Birth weight | ||||||||
| ≤2.0 kg:>2.0 kg | 12:46 | 12:15 | 3.07 | 1.14-8.25 | .02 | 1.82 | 0.21-15.55 | .58 |
| >2.0 kg | 1.00 | Reference | 1.00 | Reference | ||||
| Gestational age at birth | ||||||||
| <34 wk:≥34 wk | 9:49 | 12:15 | 4.35 | 1.54-12.32 | .006 | 0.44 | 0.05-3.59 | .44 |
| ≥34 wk | 1.00 | Reference | 1.00 | Reference | ||||
| Sex | ||||||||
| Female:male | 27:31 | 14:13 | 1.23 | 0.49-3.08 | .64 | |||
| Male | 1.00 | Reference | ||||||
| RSV-positive:RSV-negative | 14:44 | 5:22 | 0.71 | 0.22-2.23 | .56 | |||
| RSV-negative | 1.00 | Reference | ||||||
| ≥2 home apneas:1 home apnea:no home apnea | 19:27:12 | 13:4:10 | 0.82∗ | 0.27-2.45 | .72 | 0.95 | 0.19-4.62 | .95 |
| 1 home apnea | 0.17 | 0.04-0.68 | .012 | 0.28 | 0.03-2.21 | .23 | ||
| No home apnea | 1.00 | Reference | 1.00 | Reference | ||||
| Staff-observed apnea before study entry:no staff-observed apnea before study entry | 32:26 | 23:4 | 4.67 | 1.43-15.22 | .011 | 5.37 | 0.84-34.27 | .07 |
| Apnea not observed by staff before study entry | 1.00 | Reference | 1.00 | Reference | ||||
| Temperature | ||||||||
| <38°C:≥38°C | 50:8 | 25:2 | 0.50 | 0.09-2.53 | .40 | |||
| ≥38°C | 1.00 | Reference | ||||||
| Any positive pressure including high-flow oxygen (1-10 L):no positive pressure | 32:26 | 25:2 | 10.15 | 2.19-46.92 | .003 | 9.98 | 1.54-64.79 | .016 |
| No positive pressure | 1.00 | Reference | 1.00 | Reference | ||||
| Chest radiography | ||||||||
| No lobar consolidation/collapse:lobar consolidation/collapse |
38:20 | 18:9 | 0.95 | 0.36-2.49 | .91 | |||
| Lobar consolidation/collapse | 1.00 | Reference | ||||||
| pH | ||||||||
| <7.25:≥7.25 | 9:39 | 9:15 | 0.38 | 0.12-1.15 | .08 | 0.63 | 0.14-2.82 | .54 |
| ≥7.25 | 1.00 | Reference | 1.00 | Reference | ||||
| PCO2 | ||||||||
| <50:≥50 | 21:27 | 9:15 | 1.29 | 0.47-3.53 | .61 | |||
| ≥50 | 1.00 | Reference | ||||||
| PvO2 | ||||||||
| <40:≥40 | 13:35 | 1:23 | 8.54 | 1.04-69.8 | .04 | 29.44 | 2.43-356.04 | .008 |
| ≥40 | 1.00 | Reference | 1.00 | Reference | ||||
PvO2, venous PO2; RSV, respiratory syncytial virus.
Multivariate risk factors were analyzed if univariate analysis showed P < .10 or were considered clinically important a priori.
∗
0.82 refers to OR for further apnea in children with ≥2 home apneas.