A pilot study of the relationship between Down's syndrome and hearing loss

OBJECTIVE: Hearing loss is one of the most common disabilities in children with Down's syndrome. The objective of this study is to investigate the incidence and types of hearing loss in Down's syndrome patients.

METHODS: Twenty-six subjects with Down's syndrome aged between 2 and 17 year old were evaluated during the year 1998, referred randomly by the Pediatric Department and the Down's Syndrome Centre. Screening audiological procedures were used to evaluate these patients, which include behavioral audiometry, play and pure tone audiometry, tympanometry and ABR, which is the measurement of the activity of the auditory pathway structures from the distal auditory nerve to the midbrain using clicks or tonepips.

RESULTS: The study showed that 35% were found to have normal hearing compared to 4% found to have sensorineural hearing loss, while the majority of patients were found to have a conductive hearing loss (50%).

CONCLUSION: Hearing evaluation of children with Down's syndrome revealed a high prevalence of conductive hearing loss. This study proposed that this might be attributed to eustachian tube dysfunction and middle ear ciliary malfunction. Further diagnostic studies need to be carried out.