Table 4. Adjusted associations between longitudinal factors and BPD.
| Longitudinal variable | Odds ratio (95% confidence interval)a | P valueb | |
|---|---|---|---|
| Surfactant usec | 2.71 (1.37, 5.37) | 0.0042 | |
| Symptomatic PDA | 2.32 (1.25, 4.31) | 0.0080 | |
| Postnatal indomethacin usec | 1.28 (0.67, 2.45) | 0.46 | |
| Mechanical ventilation at any time in the first 6 days after admission | 2.70 (0.94, 7.74) | 0.064 | |
| Postnatal steroid usec | 5.56 (2.87, 10.78) | <0.0001 | |
| Average fluid intake (ml/kg/day) in the first 6 days after admission | 1.50 (1.02, 2.20) | 0.038 | |
| Intralipid intake (gm/kg/day)c | 1.37 (0.96, 1.95) | 0.079 | |
| Paco2 <35 torr | |||
| Intercept for AUC >0 (vs. AUC = 0) | 1.62 (0.60, 4.38) | 0.34 | |
| Slope for AUC >0 | 0.85 (0.63, 1.15) | 0.28 | |
| Joint test | 0.43 | ||
| Paco2 >50 torr | |||
| Intercept for AUC >0 (vs. AUC = 0) | 3.37 (1.69, 6.69) | 0.0005 | |
| Slope for AUC >0 | 1.18 (0.86, 1.62) | 0.30 | |
| Joint test | 0.0004 | ||
| Fio2 > 0.21 | |||
| Intercept for AUC >0 (vs. AUC = 0) | 6.15 (0.78, 48.8) | 0.086 | |
| Slope for AUC >0 | 1.78 (1.30, 2.43) | 0.0003 | |
| Joint test | 0.0002 | ||
| Fio2 >0.40 | |||
| Intercept for AUC >0 (vs. AUC = 0) | 2.33 (1.03, 5.24) | 0.041 | |
| Slope for AUC >0 | 1.50 (1.08, 2.10) | 0.017 | |
| Joint test | 0.0023 | 0.0023 | |
| MAP >0 cm H2O | |||
| Intercept for AUC >0 (vs. AUC = 0) | 0.96 (0.29, 3.23) | 0.95 | |
| Slope for AUC >0 | 2.61 (1.78, 3.81) | <0.0001 | |
| Joint test | <0.0001 |
PDA patent ductus arteriosus, AUC area under the curve (for the first 6 days after admission), Paco2 partial pressure of carbon dioxide, Fio2 fraction of inspired oxygen, MAP mean airway pressure
Logistic regression with baseline adjustment terms: birth weight, SNAP, SNAP squared, gender (male), and Apgar score <7 at 5 min; separate logistic regression model for each longitudinal variable; sample sizes vary due to missing values; AUCs are based on the first 6 days after admission
Odds ratios for continuous predictors correspond to the following unit changes: birth weight, 100 g; AUCs (linear terms), one standard deviation computed among those with AUC >0; others, one standard deviation
One degree of freedom Wald chi-square test; joint test for AUCs based on a two degree of freedom Wald chi-square test of the indicator variable for AUC >0 and the linear term for the AUC
Prior to 36 weeks post-menstrual age