Background and Objectives: Occupational noise exposure is a significant risk factor for hearing loss, affecting approximately 5% of the global population. Although noise-induced hearing loss is commonly associated with reduced sensitivity to pure tones, there is limited information regarding when this hearing loss begins after noise exposure. This study aimed to investigate the time of onset of hearing loss in bus drivers exposed to noise for varying durations. Subjects and Methods: The study involved 102 bus drivers aged 25-40 years who had been exposed to noise for periods ranging from 6 months to over 10 years. A control group comprising 102 age-matched individuals without noise exposure was also included. Pure-tone audiometry was performed to assess hearing loss, and time of onset of hearing loss relative to noise exposure duration was evaluated. Results: Bus drivers experienced only “slight” hearing loss, even after 10 years of noise exposure. By contrast, reduced sensitivity to pure tones was observed after 25 to 48 months of exposure. Conclusions This study confirms that prolonged noise exposure leads to “slight” hearing loss, which can appear as early as 25-48 months after exposure to noise. Among individuals under 40 years of age, significant hearing loss appeared to occur only after 10 or more years of exposure. These findings suggest that the impact of noise on hearing acuity may have been overestimated in previous studies.

Background and Objectives: Occupational noise exposure is a significant risk factor for hearing loss, affecting approximately 5% of the global population. Although noise-induced hearing loss is commonly associated with reduced sensitivity to pure tones, there is limited information regarding when this hearing loss begins after noise exposure. This study aimed to investigate the time of onset of hearing loss in bus drivers exposed to noise for varying durations. Subjects and Methods: The study involved 102 bus drivers aged 25-40 years who had been exposed to noise for periods ranging from 6 months to over 10 years. A control group comprising 102 age-matched individuals without noise exposure was also included. Pure-tone audiometry was performed to assess hearing loss, and time of onset of hearing loss relative to noise exposure duration was evaluated. Results: Bus drivers experienced only “slight” hearing loss, even after 10 years of noise exposure. By contrast, reduced sensitivity to pure tones was observed after 25 to 48 months of exposure. Conclusions This study confirms that prolonged noise exposure leads to “slight” hearing loss, which can appear as early as 25-48 months after exposure to noise. Among individuals under 40 years of age, significant hearing loss appeared to occur only after 10 or more years of exposure. These findings suggest that the impact of noise on hearing acuity may have been overestimated in previous studies.

Background and Objectives: Occupational noise exposure is a significant risk factor for hearing loss, affecting approximately 5% of the global population. Although noise-induced hearing loss is commonly associated with reduced sensitivity to pure tones, there is limited information regarding when this hearing loss begins after noise exposure. This study aimed to investigate the time of onset of hearing loss in bus drivers exposed to noise for varying durations. Subjects and Methods: The study involved 102 bus drivers aged 25-40 years who had been exposed to noise for periods ranging from 6 months to over 10 years. A control group comprising 102 age-matched individuals without noise exposure was also included. Pure-tone audiometry was performed to assess hearing loss, and time of onset of hearing loss relative to noise exposure duration was evaluated. Results: Bus drivers experienced only “slight” hearing loss, even after 10 years of noise exposure. By contrast, reduced sensitivity to pure tones was observed after 25 to 48 months of exposure. Conclusions This study confirms that prolonged noise exposure leads to “slight” hearing loss, which can appear as early as 25-48 months after exposure to noise. Among individuals under 40 years of age, significant hearing loss appeared to occur only after 10 or more years of exposure. These findings suggest that the impact of noise on hearing acuity may have been overestimated in previous studies.

BACKGROUND AND OBJECTIVES: The auditory profile of a large number of persons with late onset auditory neuropathy spectrum disorder (ANSD) is recently described in the Indian context. The purpose of study was 1) to profile data on routine audiological parameters, cortical evoked potentials, and temporal processing, 2) to analyze the benefit from hearing aids for persons with ANSD, and 3) to understand the association between benefit from hearing aids and auditory profile. SUBJECTS AND METHODS: Thirty-eight adults with late onset ANSD and a matched group of 40 normally hearing adults participated in the study. Basic audiological tests, recording of cortical evoked potentials, and temporal processing tests were carried out on both groups of participant while only persons with ANSD were fitted with hearing aid. RESULTS: Subjects in the two groups were significantly different on all the audiological parameters. ANSD group seemed to benefit from hearing aids variably. The mean amplitude of N2 was significantly different between normally-hearing participants and patients with ANSD. CONCLUSIONS: Residual temporal processing, particularly amplitude modulation detection seems to be associated with benefit from hearing aids in patients with ANSD.
Adult* ; Evoked Potentials ; Hearing ; Hearing Aids ; Humans ; Research Design