Prevalence and impact of chronic otitis media in school age children in Brazil. First epidemiologic study concerning chronic otitis media in Latin America.

OBJECTIVE

The first epidemiological study carried out in Latin America to investigate the prevalence of otological disease and its impact in a representative random sample of the school children population.

METHODS

A cross sectional epidemiological survey to investigate the epidemiology of otitis in a representative random sample of 1119 children and adolescents from a total of 486166 elementary and high-school students, aged 6-18 years, regularly registered in one of the 521 public and private schools of the city of Belo Horizonte, in the state of Minas Gerais, southern Brazil. The interviews were conducted individually, in the school, by an otolaryngologist or a pediatrician. The interview included all of the personal data and also detailed questions regarding otological disorders and hearing. The otological examination was carried out with Mini-Heine otoscopes and the audiometric evaluation with the AudioScope 3 with 25dB intensity. The questionnaire and basic procedures for medical examination had been previously tested through a pilot test in two schools.

RESULTS

The prevalence of chronic otitis media was 0.94%. Impacted wax was found in 12.3% of the students. The prevalence of abnormalities (excluding wax) in the otoscopy examination was 10.5%. It was found that 8.3% of students had a past history of otitis and 7.7% had a past history of otorrhea. These two special groups presented statistically significant associations with chronic otitis media, hearing loss and otolaryngological surgeries (when compared with the other school children). Parents and school children seemed significantly able to identify a special group of children with past history of otitis during childhood.