A randomised controlled trial of screening for adult hearing loss during preventive health checks

Background: Prophylactic strategies to counter acquired hearing impairment may involve routine audiometric screening of asymptomatic working-age adults attending general practice for regular health checks. Aim: To evaluate the effect of adult hearing screening on subsequent noise exposure and hearing. Design of study: A randomised controlled population-based study of health checks and health discussions in general practice. Setting: The project was initiated in the district of Ebeltoft, Aarhus county, Denmark. Method: Intervention group participants' hearing thresholds were determined audiometrically at 0.5, 1, 2, 3, and 4 kHz in the average hearing loss exceeded 20 dB hearing level (dBHL) in either ear. Noise avoidance was emphasised when thresholds exceeded 25 dBHL bilaterally at 4 kHz. Follow-up included questionnaires and audiometry. Results: Hearing loss was observed among 18.9% of the study sample at baseline. At the five-year follow-up we recorded no significant differences between the control and the intervention groups regarding subjective or objective hearing, or exposure to occupational noise. However, there was a tendency towards reduction in exposure to leisure noise among intervention participants (P = 0.045). Approximately 20% reported hearing problems; 16.5% reported tinnitus-related complaints; 0.8% used hearing aids; 35.0% reported frequent noise exposure; and occluding wax was suspected in 2.1%. Conclusion: Preventive health checks with audiometry did not significantly affect hearing, but leisure noise exposure tended to become less frequent. The poor effect may be ascribed to inadequate audiological counselling or a higher priority to other advice, e.g. on cardiovascular risk or lifestyle.