Total | Wheezing phenotypes | |||
Never | Early | Persistent | ||
Subjects n | 325 | 144 | 127 | 54 |
Males | 53 | 49 | 55 | 59 |
Age yrs | 4.4±0.2 | 4.4±0.2 | 4.4±0.2 | |
Height cm | 106.4±4.5 | 106.1±4.3 | 106.0±3.4 | |
Weight kg | 17.6±2.1 | 17.5±2.3 | 17.6±2.0 | |
Education level of mother# | ||||
Low | 21 | 19 | 22 | 23 |
High | 79 | 81 | 78 | 77 |
Atopy of mother¶ | 43 | 45 | 43 | 35 |
Parental smoking+ at 4 yrs | 5 | 6 | 4 | 6 |
Siblings at 4 yrs | 87 | 85 | 87 | 92 |
Exposure to pets§ at 4 yrs | 57 | 58 | 55 | 59 |
Eczema of childƒ | 53 | 50 | 55 | 58 |
Rhinitis of childƒ | 76 | 73 | 75 | 86 |
Atopy of child¶ | 28 | 23 | 29 | 41* |
LRTI at 4 yrs | 15 | 7 | 15* | 36*** |
Antibiotics at 4 yrs | 46 | 39 | 46 | 65*** |
Data are presented as mean±sd or %, unless stated otherwise. LRTI: lower respiratory tract infection (a serious lung or airways infection). #: high if the mother had completed a bachelor or master's degree, otherwise low; ¶: defined as a specific immunoglobulin E level ≥0.35 kU·L−1 at the medical examination at 1 or 4 yrs; +: regular exposure to tobacco smoke by either of the parents; §: regular exposure to a cat or dog; ƒ: a positive answer to the following question in any of the questionnaires: “Did your child suffer from eczema/rhinitis during the past 6 months?” 12. At 4 yrs: a positive answer in the questionnaire returned at 42 or 48 months.*: p<0.05, relative to those who never wheeze; ***: p<0.001, relative to those who never wheeze.