-
Comparisons of hearing threshold changes in male workers with unilateral conductive hearing loss exposed to workplace noise: a retrospective cohort study for 8 years
-
Sang Jin Park, Joo Hyun Sung, Chang Sun Sim, Seok Hyeon Yun, Jeong Han Yeom, Joong-Keun Kwon, Jiho Lee
-
Ann Occup Environ Med 2016;28:51. Published online September 22, 2016
-
DOI: https://doi.org/10.1186/s40557-016-0132-1
-
-
Abstract
PDFPubReaderePub
- Background
The purpose of this study was to investigate hearing threshold changes of workers with unilateral conductive hearing loss who were exposed to workplace noise for 8-years. MethodsAmong 1819 workers at a shipyard in Ulsan, 78 subjects with an air-bone gap ≥10 dBHL in unilateral ears were selected. Factors that could affect hearing were acquired from questionnaires, physical examinations, and biochemistry examinations. Paired t-test was conducted to compare the hearing threshold changes over time between conductive hearing loss (CHL) ear and sensorineural hearing loss (SNHL) ear. ResultsThe study included male subjects aged 48.7 ± 2.9, having worked for 29.8 ± 2.7 years. Hearing thresholds increased significantly in CHL ears and SNHL ears at all frequencies (0.5–6 kHz) during follow-up period (p < 0.05). The threshold change at 4 kHz was 3.2 dBHL higher in SNHL ears which was statistically significant (p < 0.05). When workers were exposed to noise levels of 85 dBA and above, threshold change at 4 kHz was 5.6 dBHL higher in SNHL ears which was statistically significant (p < 0.05). Among workers aged below 50, the threshold change values were lower in low-frequency (0.5–2 kHz) in SNHL ears, with a small range of changes, whereas in high-frequency (3–6 kHz), the range of changes was greater SNHL ears (p < 0.05). Among workers aged 50 and above, SNHL ears showed a wider range of changes in both high- and low-frequency areas (p < 0.05). ConclusionsAt high-frequencies, particularly at 4 kHz, the range of hearing threshold changes was lower in ears with conductive hearing loss than in contralateral ears. This is suggested as a protective effect against noise exposure.
-
Citations
Citations to this article as recorded by
- Prevalence of Pre-Existing Hearing Loss Among Patients With Drug-Resistant Tuberculosis in South Africa
Hyejeong Hong, David W. Dowdy, Kelly E. Dooley, Howard W. Francis, Chakra Budhathoki, Hae-Ra Han, Jason E. Farley American Journal of Audiology.2020; 29(2): 199. CrossRef
-
72
View
-
0
Download
-
1
Web of Science
-
1
Crossref
|