| BPD36w (n = 163) | No BPD (n = 56) | BPD vs no BPD | Comparison group (n = 148) | No BPD vs comparison group | ||||
| n | % | n | % | OR (95% CI) | n | % | OR (95% CI) | |
| Height (cm), mean (quartiles) | 111 (109; 117) | 113 (109; 117) | 121 (111; 122) | |||||
| Height SD score, mean (quartiles) | −0.98 (−1.61; −0.31) | −0.87 (−1.68; −0.27) | 0.0 (−0.89; 0.56) | |||||
| Weight (kg), mean (quartiles) | 18.7 (16.5; 20.5) | 18.7 (17.1; 20.0) | 21.6 (18.5; 23.5) | |||||
| Weight SD score, mean (quartiles) | −1.22 (−2.10; −0.37) | −1.15 (−1.75; −0.38) | 0.07 (−0.71; 0.73) | |||||
| Wheezed in past year | 59 | 36.2 | 11 | 19.6 | 2.3 (1.1 to 4.8)* | 19 | 12.8 | 1.7 (0.73 to 3.8) |
| Had episodes in past year | 57 | 10 | 19 | |||||
| Number of episodes in past year | ||||||||
| 1–3 | 29 | 50.9 | 7 | 70.0 | p = 0.35† | 12 | 63.2 | p = 0.89† |
| 4–12 | 20 | 35.1 | 2 | 20.0 | 7 | 36.8 | ||
| >12 | 8 | 14.0 | 1 | 10.0 | 0 | – | ||
| Severe episodes | 18 | 11.0 | 2 | 3.6 | 3.3 (0.75 to 14.9) | 2 | 1.4 | 2.7 (0.37 to 19.7) |
| Wheeze or cough at night | 51 | 31.3 | 9 | 16.1 | 2.3 (1.1 to 5.0)* | 16 | 10.8 | 1.6 (0.66 to 3.8) |
| Wheeze on exercise | 42 | 25.9 | 9 | 16.1 | 1.8 (0.82 to 4.0) | 17 | 11.6 | 1.5 (0.61 to 3.5) |
| Inhaled medications | ||||||||
| Bronchodilators last 12 months | 49 | 27.8 | 9 | 16.1 | 2.2 (1.0 to 4.8)* | 18 | 11.3 | 1.4 (0.59 to 3.3) |
| Steroids last 12 months | 42 | 23.9 | 7 | 11.7 | 2.4 (1.0 to 5.6)* | 15 | 9.4 | 1.3 (0.49 to 3.3) |
| Bronchodilators currently | 26 | 14.8 | 3 | 5.0 | 3.3 (0.96 to 11.3) | 11 | 6.9 | 0.71 (0.19 to 2.6) |
| Steroids currently | 31 | 17.6 | 4 | 6.7 | 3.0 (1.0 to 8.9)* | 11 | 6.9 | 0.97 (0.30 to 3.2) |
| Current paediatrician surveillance | 32 | 19.8 | 5 | 8.9 | 2.5 (0.93 to 6.8) | 6 | 4.1 | 2.3 (0.67 to 7.9) |
| Ever diagnosed as “asthma” | 71 | 44.1 | 20 | 35.7 | 1.4 (0.76 to 2.7) | 32 | 21.9 | 2.0 (1.0 to 3.9) |
| n = 134 | n = 53 | Difference in means (95% CI) | n = 142 | Difference in means (95% CI) | ||||
| Peak expiratory flow (l/min), mean (SD) | 133 | (37) | 154 | (44) | 20 (7 to 33)‡ | 182 | (42) | 29 (15–42)‡ |
| p = 0.003 | p = 0.002 | |||||||
*Significant odds ratios; †χ2 for trend; ‡t test.
Forms were returned for 219 extremely preterm and 148 comparison children; BPD defined as oxygen use at 36 weeks postmenstrual age. BPD, bronchopulmonary dysplasia; OR, odds ratio.