[Epidemiology of passive smoking of children from 0 to 6 years (author's transl)].

An epidemiologic survey was carried out in the South of France, concerning 892 children less than 6 years of age who were examined or hospitalized for various reasons. Smoking is significantly more important in parents of coughing children than in children who do not cough. The percentage of coughing children increases with the amount of smoking of their parents. A statistically significant relationship is found between the annual incidence of bronchopneumopathies and the total number of cigarettes smoked inside the house. A respiratory index expressed as the sum of 6 parameters representative of the respiratory infectious status of the children is correlated with parental smoking. This study also shows the enhancing effect of day care centers and nursery schools and of collective heating, difficult to adjust. This emphasizes the role of environmental factors and the multifactorial character of respiratory diseases in pre-school children.