Abstract Background Traffic police personnel in rapidly urbanizing Indian cities are chronically exposed to hazardous noise levels, placing them at high risk for noise-induced hearing loss (NIHL). Conventional pure-tone audiometry (PTA) often fails to detect the earliest signs of cochlear damage. This study aims to evaluate and compare the utility of high-frequency audiometry (HFA) and distortion product otoacoustic emissions (DPOAE) in detecting early auditory damage in traffic police personnel with normal conventional audiograms. Methods A cross-sectional comparative study was conducted at a tertiary care teaching hospital in Bangalore over 13 months on 120 participants. The cohort was divided into Group 1 (60 traffic police personnel) and Group 2 (60 office workers). All participants had normal conventional PTA thresholds (≤ 25 dB HL at 0.25–8 kHz). Participants underwent HFA (10–16 kHz) and DPOAE testing. Results Despite normal conventional hearing, Group 1 exhibited significantly higher thresholds in HFA at 12.5 kHz and 16 kHz ( p < 0.001). DPOAE analysis revealed significantly reduced signal-to-noise ratios (SNR) and lower emission amplitudes in Group 1, particularly at 4 kHz and 6 kHz. Conclusion Traffic police personnel suffer from latent cochlear damage missed by routine screening. HFA and DPOAE are sensitive tools for the preclinical detection of NIHL and should be considered for occupational surveillance protocols.
Shwetha Poojary (Tue,) studied this question.