Auditory Differences in Occupationally Noise-Exposed Workers With Normal Conventional Audiograms: A Multi-Measure...

Area of Science:

• Audiology
• Occupational Health
• Noise-Induced Hearing Loss

Background:

• Conventional audiometry may fail to detect early auditory changes in young adults exposed to occupational noise.
• Subtle hearing deficits can precede significant hearing loss, impacting communication and well-being.

Purpose of the Study:

• To evaluate a clinically feasible test battery for detecting early noise-related auditory differences in young adults.
• To compare audiological measures between occupationally noise-exposed workers and low-noise controls.

Main Methods:

• A test battery including conventional and extended high-frequency audiometry, distortion-product otoacoustic emissions (DPOAEs), acoustic reflex thresholds (ARTs), auditory brainstem responses (ABRs), and speech-in-noise (SiN) testing was administered.
• 280 noise-exposed workers and 100 controls (20-40 years) participated.

Main Results:

• Noise-exposed participants exhibited elevated ARTs, poorer extended high-frequency thresholds, and reduced DPOAE levels compared to controls.
• Auditory brainstem response metrics did not differ between groups.
• Poorer SiN performance (higher SNR-50) was observed in the noise-exposed group, associated with conventional hearing thresholds and cumulative noise exposure.

Conclusions:

• Cochlear-status measures (DPOAEs), conventional ARTs, and SiN performance offer valuable information beyond conventional audiometry for occupational hearing surveillance.
• These tests can identify early auditory changes missed by routine screening, aiding in the prevention of noise-induced hearing loss.