Protracted secretory otitis media. The impact of familial factors and day-care center attendance.

This study's objective was to assess the impact of familial factors, day-care center attendance, and passive smoking on the incidence of protracted secretory otitis media (SOM). An unselected cohort of 1306 Swedish children were followed from birth to 7 years of age. Information about physician visits and insertions of tympanostomy tubes for SOM was collected at the ENT-departments in one Swedish county. The material was analyzed by life table methods and Cox's regression analysis. At the ages of 3, 5 and 7 years, 1%, 4% and 6%, respectively, of the children had been treated by tympanostomy tubes for SOM. The cumulative incidence of protracted SOM was four times higher among the children who had a sibling with the same health problem. Attendance at a day-care center of 12 or more months during the first 4 years of life increased the risk for protracted SOM by 2.6 times. No association was found between parents' smoking habits and the incidence of protracted SOM.