Parental smoking and risk of otitis media in pre-school children.

This study was designed to estimate the role of passive smoking in the occurrence of repeated acute otitis media among pre-school children. The parents of 918 children, who were part of a birth cohort, were interviewed when the children were four years old. The frequency of episodes of otitis media was determined, as well as the age at which the first such episode occurred. Information about smoking in the home had been obtained when the child was two weeks old and again at 6, 12, 18 and 40 months of age. In all, 119 mothers (13%) smoked at least 20 cigarettes a day on average, 205 (22%) smoked less than 20, and 593 (65%) stated that they did not smoke at all. Children of mothers who smoked 20 or more cigarettes per day were at significantly increased risk of having four or more episodes of acute otitis media: relative risk (RR) = 1.8, 95% confidence interval (CI) = 1.1-3.0 and of having their first episode earlier in life RR = 1.3 (CI = 1.0-1.8), after adjustment. Moreover, the risk of recurrent (> or = four episodes) otitis media increases with the amount of cigarettes smoked. These findings clearly strengthen the case for persuading parents not to smoke in the presence of young children.