Domestic passive smoking in children and lower respiratory conditions in a Primary Care setting

Objective: to study the relationship between domestic passive smoking and bronchiolitis and/or asthmatic bronchitis episodes in children under 7 years from a Primary Care paediatric clinic in Madrid.

Subjects and methods: cross-sectional retrospective study. Information was collected by questionnaires in 506 children aged less than 7 years. The chi-square test was used to compare percentages. A multiple logistic and lineal regression was carried out.

Results: twenty four and eleven percent of children had bronchiolitis and 26.87% suffered asthmatic bronchitis episodes. Multivariant analysis showed that bronchiolitis was positively associated with maternal smoking and asthmatic bronchitis episodes were associated with previous bronchiolitis. The number of respiratory events was positively associated with previous bronchiolitis, with a history of prematurity and with the total amount of cigarettes smoked per day by both parents.

Conclusions: maternal smoking is a risk factor for bronchiolitis, which in turn is a risk factor for future asthmatic bronchitis episodes. The risk factors related to the number of asthmatic bronchitis episodes per year are: other previous bronchiolitis, the number of cigarettes smoked  by parents and a history of prematurity.