Table 2

Background variables (n=286)

Cohort82–85 cohort91–92 cohort99–00 cohort
Participated/eligible*Term-born46/46(100)35/35(100)57/57(100)
EP-born49/51(96)35/35(100)64/88(73)
Female sex, n (%), p valueTerm-born21(46)22(63)27(47)
EP-born21(43)22(63)31(48)
Final Height in cm, mean (SD), p valueTerm-born174(8)0.04171(9)0.09177(10)<0.001
EP-born170(8)167(9)168(10)
Adult Weight in kg, mean (SD), p valueTerm-born73(14)0.7373(14)0.3473(14)0.02
EP-born74(18)69(14)66(14)
Self-reported smoking, n (%), p valueTerm-born16(35)0.428(23)0.04−†
EP-born21(43)2(6)2(6)
Atopy, n (%), p valueTerm-born20(43)0.138(23)0.7820(40)0.04
EP-born13(28)9(26)12(22)
Wheeze last 12 months, n (%), p valueTerm-born17(38)0.2715(43)0.347(13)0.10
EP-born24(49)19(54)15(24)
Asthma med. last 12 months, n (%), p valueTerm-born6(13)0.344(13)0.173(5)0.25
EP-born10(20)9(26)7(11)
Asthma ever, n (%), p valueTerm-born9(20)0.0610(29)0.145(9)<0.001
EP-born18(37)16(46)22(35)
Current asthma, n (%), p valueTerm-born6(13)0.108(23)0.294(7)0.31
EP-born13(27)12(34)8(13)
  • The listed variables ‘Allergy’, ‘self-reported smoking’, ‘wheeze last 12 months’ and ‘asthma med. last 12 months’ refer to the number (fraction) with a least one positive response or finding at any visit. ‘Current asthma’ refers to a combination of wheeze in the last 12 months plus a positive response to the questions ‘asthma ever’ or ‘asthma medication last 12 months’ on minimum one visit. P value refers to comparisons between EP and term-born (Welch’s t-test for continuous data and Pearson’s χ2 test for categorical data).

  • *At least one visit (all percentage and p values are based only on visits where the subject participated).

  • †Data not presented due to large amount of missing data.

  • Adult weight, weight at 25 years (or 18 years if not applicable); Asthma med, asthma medication; EP, subjects born extremely preterm or with extremely low birth weight (gestational age ≤28 weeks or birth weight ≤1000 g); Final height, the height achieved at 18 or 25 years, whichever was highest.