Setting: Children's Hospital for Respiratory Diseases and Tuberculosis, Belgrade, Serbia.
Objectives: To compare parents' educational level and smoking habits with asthma in children exposed to environmental tobacco smoke (ETS) and in those not exposed.
Methods: In this cross-sectional study, 231 asthmatic children (average age 10.6 years, 49% boys) from smoking and non-smoking families were compared by birth weight, birth length, first episode of wheezing, number of respiratory infections and exacerbations per year, severity of asthma, number of hospitalisations, total serum immunoglobulin E (IgE), skin prick tests and allergic manifestations.
Results: In our study, 77% of the children were from smoking families: 45.9% had active smoking mothers and 51% active smoking fathers. Smoking was more common among parents with lower education level. The mother being the only smoker in the family had a greater impact on respiratory infections and asthma exacerbations in the first years of life; however, after the third year, the effect of having both smoking parents was important. Children exposed to ETS had more allergic manifestations. The percentage of children with both non-smoking parents decreased and that of children with both smoking parents increased with increasing asthma severity (χ(2) = 17.73, P < 0.05).
Conclusion: ETS has a negative impact on illness among children with asthma.