Hearing investigation in the Iwaki Health Promotional Project

The goal of the Iwaki Health Promotional Project was to prevent illness and promote health in the population of Iwaki town. In our study, a part of this Project, we used hearing tests and questionnaires about hearing. Pure-tone audiometry and questionnaire surveys for the symptoms of tinnitus, ear fullness and hearing impairment were performed with 956 participants. The hearing threshold levels obtained for each participant were analyzed separately by gender and age. The results revealed that age-related hearing loss tended to be more progressive at higher frequencies. Furthermore, the average of hearing thresholds at 4, 000Hz in people in their 50's, 60's, 70's and 80's were higher in males than in females. The percentages of participants complaining of tinnitus, ear fullness and hearing impairment were 32.2%, 15.9% and 36.9%, respectively. Many of the participants, especially in their 70's and 80's complained of hearing impairment, whereas the percentage of participants complaining of tinnitus was relatively low.