Table 1

Background variables for 83 subjects born extremely preterm with and without neonatal bronchopulmonary dysplasia (BPD) and 81 term-born control subjects

 1991–1992 cohort1982–1985 cohort
Mean (SD) age (years)10.5 (0.4)17.8 (0.4)17.7 (1.2)24.9 (1.2)
Total NControl35294640
Preterm35314643
Maternal smoking in pregnancyControl9 (26)10 (22)
Preterm13 (37)22 (48)*
Current self-reported smokingControl5 (17)14 (30)8 (20)
Preterm1 (3)15 (33)17 (40)
Allergy†Control8 (23)20 (44)
Preterm9 (26)13 (28)
Wheeze last 12 monthsControl2 (6)10 (34)12 (27)8 (20)
Preterm11 (31)*12 (39)16 (35)18 (42)
Asthma medication last 12 monthsControl1 (3)1 (3)1 (2)3 (8)
Preterm5 (14)7 (23)7 (16)5 (12)
Current asthma‡Control1 (3)5 (17)3 (7)3 (8)
Preterm10 (29)**6 (19)8 (17)8 (19)
  • Data shown are n (%).

  • *p<0.05 and **p<0.01, preterm vs term-born control subjects within the same birth cohort (Pearson exact χ2 test).

  • †Allergy denotes hypersensitivity to at least one tested allergen (at least one positive skin prick or specific serum IgE test).

  • ‡A combination of wheeze in last 12 months plus either ‘asthma ever’ or asthma medication in last 12 months.