Audiological Methods for Early Detection of Hearing Loss in Healthcare Worker

Abstract

Background: Occupational hearing loss (OHL) is a primary concern in industrial settings. In hospitals, the healthcare workers are also exposed to noise and chemical agents, the reported hearing loss in this occupation is underestimated. Hearing examination is routinely evaluated in the range of conventional frequencies, which may not detect hearing problems early. Therefore, this study aimed to reveal the hearing thresholds among medical personnel exposed to loud noise and/or chemical environments, estimating the prevalence of hearing loss using four different audiological methods. Methods: One hundred and thirty-one medical personnel were recruited from different units at the same hospital and grouped into noise, chemical, and mixed exposure categories. The hearing thresholds were assessed using four audiological methods, conventional audiometry (CA), extended high-frequency audiometry (EHFA), standard frequency distortion product otoacoustic emission (DPOAE), and ultra-high-frequency DPOAE. Statistical analyses were performed using R. Results: Ultra-high-frequency DPOAE and EHFA showed a higher prevalence of hearing loss than CA and DPOAE. Even CA usually demonstrated hearing threshold within normal limits, this study found a notch audiogram pattern indicating a decline in hearing loss over time at frequencies of 2, 3, and 4 kHz in each age group and a sign at a frequency of 6 kHz. Conclusions: Evidence of hearing loss can be identified with ultra-high-frequency DPOAE and EHFA, despite conventional audiometry indicating normal hearing thresholds.