Table 5

Association between combinations of maternal smoking in the child's first year of life and current smoking and symptoms of asthma, eczema and rhinoconjunctivitis at 6−7 years of age

SymptomFirst year of life onlyCurrent onlyBoth timesRERI
Current wheeze1.38 (1.24 to 1.53)1.23 (1.14 to 1.32)1.39 (1.31 to 1.47)−0.218 (−0.432 to −0.004)
Severe asthma symptoms1.36 (1.17 to 1.58)1.21 (1.09 to 1.34)1.48 (1.36 to 1.61)−0.093 (−0.405 to 0.219)
Asthma ever1.41 (1.27 to 1.56)1.20 (1.11 to 1.30)1.37 (1.28 to 1.45)−0.247 (−0.462 to −0.031)
Current eczema symptoms1.19 (1.06 to 1.33)1.11 (1.03 to 1.20)1.21 (1.13 to 1.29)−0.089 (−0.293 to 0.114)
Current rhinoconjunctivitis symptoms1.18 (1.05 to 1.33)1.07 (0.99 to 1.16)1.16 (1.09 to 1.24)−0.097 (−0.299 to 0.106)
Eczema symptoms without wheeze1.13 (0.99 to 1.29)1.10 (1.01 to 1.20)1.11 (1.02 to 1.20)−0.086 (−0.317 to 0.145)
Rhinoconjunctivitis symptoms without wheeze1.08 (0.93 to 1.25)1.03 (0.94 to 1.13)1.03 (0.94 to 1.12)−0.123 (−0.343 to 0.096)
  • Data are OR (95% CI) and are adjusted for gender, language, region and GNI category. Reference group: mother non-smoker for first year of child's life and non-smoker now.

  • RERI, relative excess risk due to interaction between the two smoking exposures.