Asthmatic symptoms | Wheeze | Nocturnal dyspnoea | Bronchitic symptoms | Cough | Phlegm | Dyspnoea grade 3 | |
Perinatal factors | |||||||
Mother smoked during pregnancy | 0.91 (0.54–1.51) | 0.73 (0.28–1.90) | 0.60 (0.27–1.31) | 0.98 (0.77–1.25) | 1.09 (0.71–1.84) | 1.15 (0.72–1.86) | 0.91 (0.16–5.16) |
Being first‐born | 0.58 (0.35–0.95)* | 0.66 (0.27–1.65) | 0.74 (0.35–1.57) | 0.93 (0.64–1.36) | 1.19 (0.80–1.79) | 0.80 (0.51–1.27) | 4.75 (0.54–41.78) |
Birth weight, per 100 g increase | 1.00 (0.95–1.04) | 0.96 (0.88–1.05) | 0.60 (0.27–1.31) | 1.00 (0.96–1.03) | 1.00 (0.97–1.04) | 0.99 (0.95–1.03) | 0.98 (0.84–1.14) |
Other potential risk factors | |||||||
Severe respiratory tract infection# | 2.76 (1.51–5.04)* | 0.83 (0.30–2.29) | 2.27 (0.93–5.53)¶ | 1.57 (0.92–2.71) | 1.90 (1.08–3.33)* | 2.04 (1.12–3.72)* | 4.60 (0.77–27.48)¶ |
Current smoking | 1.70 (1.02–2.84)* | 1.01 (0.38–2.68) | 1.75 (0.80–3.82) | 2.23 (1.50–3.31)* | 2.22 (1.46–3.37)* | 1.80 (1.12–2.89)* | 1.17 (0.20–7.06) |
Family history asthma | 2.07 (1.18–3.64)* | 2.07 (0.71–6.08) | 1.80 (0.77–4.20) | 1.30 (0.80–2.12) | 1.13 (0.67–1.90) | 1.51 (0.97–2.64) | 0.00 (0.00–1.89) |
Family history allergy | 1.84 (1.09–3.10)* | 1.04 (0.41–2.66) | 2.86 (1.18–6.91)* | 1.36 (0.92–2.0) | 1.24 (0.82–1.87) | 1.07 (0.67–1.71) | 1.61 (0.28–9.26) |
Data are presented as odds ratio (95% confidence interval)
COPD: chronic obstructive pulmonary disease
Multiple logistic regression analysis estimating the effect of perinatal factors (mother smoked during pregnancy, being first-born and birth weight) on respiratory symptoms, with adjustment for other potential risk factors (severe respiratory tract infection in the first year of life, current smoking habits, family history of asthma or allergy, sex (not shown), age (not shown)
*: p<0.05
¶: p<0.10
#: in the first year of life. n=1,568