EXTENDED HIGH-FREQUENCY HEARING AND HISTORY OF ACUTE OTITIS-MEDIA IN 14-YEAR-OLD CHILDREN IN FINLAND

We studied the extended high frequency hearing of 573 white, urban, me an 13.8-year-old unselected children in Tampere, Finland. All their ea r-related morbidity had been recorded since their birth and they had b een examined at the ages of 7 months, 2 years, and some of them at 5 y ears. The extended high frequency audiometry was measured from 10 to 1 8 kHz, with 1 kHz steps, and the results were related to the number of attacks of acute otitis media (AOM) (0, 1-2, 3-7 and greater than or equal to 8) they had experienced. The mean pure lone hearing threshold s varied from 10.7 dB at 10 kHz to 37.0 dB at 18 kHz in the right ears and between 11.6 dB at 10 kHz and 37.4 dB at 18 kHz in the left ears. Among those with greater than or equal to 8 attacks of AOM the the th resholds were highest, the difference between them and each of the fir st 3 groups being statistically significant at 13 and 14 kHz. From 11 to 16 kHz the same difference was significant between the last(greater than or equal to 8 AOM) and at least 2 of the first 3 AOM groups. Num erous attacks of AOM may have a harmful effect on high frequency heari ng in the long term.