[Effects of passive smoking on the pediatric respiratory tract]

To explore the risk of parental smoking to the respiratory health of their children data of a cross sectional study on fourth-grade schoolchildren in Munich and Southern Bavaria were analysed.

Allergic and asthmatic diseases and symptoms, risk factors like family history, indoor pollution and parental smoking were evaluated by a questionnaire. Pulmonary function tests were performed in 7284 school children aged (9-11 years). Lung function values were adjusted for height, weight, sex and other confounders.

The children, whose parents smoke at home, had significantly lower levels of peak flow, MEF75, MEF50 and MEF25 compared to children from non-smoking families, with a dose-response relationship. Smoking of more than 20 cigarettes at home is associated with a mean decrease in MEF75 of 5.7%, in MEF50 of 4.9% and in Peak Flow of 4.9% (p < 0.001). The prevalence of cough and wheezing increased with increasing smoking rates of the parents.

Passive exposure to smoke has direct measurable dose-dependent effects on the respiratory system of children.