The Burden of Occupational Noise-Induced Hearing Loss From 1990 to 2019: An Analysis of Global Burden of Disease Data.

OBJECTIVES: The relationship between long-term exposure to occupational noise and hearing loss has been extensively documented. We aimed to assess spatial and temporal changes in the burden of occupational noise-induced hearing loss (ONIHL) in 204 countries and territories with varying socio-demographic indexes (SDI) from 1990 to 2019. DESIGN: Temporal and spatial trends in age-standardized disability-adjusted life year rates (ASDR) for ONIHL were estimated by sex, age, SDI level, country, and geographic region from 1990 to 2019. We used the Joinpoint model to calculate annual average percentage changes to assess such trends and projected trends in ASDR for ONIHL globally and across different income regions from 2020 to 2044 using an age-period-cohort model. We fitted the relationship between ASDR and SDI, ASDR and healthcare access and quality index, respectively. RESULTS: Overall, the global burden of ONIHL has decreased since 1990, especially in middle and lower SDI regions. In 2019, the global ASDR for ONIHL was 84.23 (95% confidence interval: 57.46 to 120.52) per 100,000 population. From 1990 to 2019, the global ASDR for ONIHL decreased by 1.72% (annual average percentage change = -0.05, 95% confidence interval: -0.07 to -0.03). Our projections showed a decreasing trend in the global ONIHL burden until 2044. ASDR and SDI ( R = -0.8, p < 0.05), ASDR and healthcare access and quality index ( R = -0.75, p < 0.05) showed significant negative correlations. CONCLUSIONS: The global ONIHL burden has decreased over the past three decades, especially in regions with middle and lower SDI levels. However, the global ONIHL burden still remained severe in 2019, notably among males, the middle-aged and elderly, and regions with lower SDI levels.

The influence of occupational noise exposure on blood pressure and hearing loss among female workers of childbearing age.

OBJECTIVES: Women exposed to occupational noise experience adverse pregnancy outcomes. Therefore, we initiated a large, population-based, cross-sectional study to further investigate the effects of occupational noise on hearing and blood pressure among female workers of childbearing age. STUDY DESIGN AND SETTING: A total of 6981 childbearing-aged female workers were selected for this cross-sectional study. Basic characteristics of participants were analyzed by comparing the exposed and control groups. Logistic regression models were employed to calculate the odds ratios (ORs) and 95% confidences intervals (CIs) for the associations of occupational noise with levels of hearing loss and blood pressure. The associations were further explored through stratification by age and duration of noise exposure. RESULTS: Compared with participants not exposed to occupational noise, increasing years of occupational noise exposure were independently associated with an elevated risk of hypertension after adjustment of age, industry classification, enterprise size and economic type. Compared to participants not exposed to occupational noise, only the prevalence of bilateral hearing loss was significantly higher after adjustments for age, industry classification, enterprise size and economic type. Compared with those with normal hearing, the ORs and 95% CIs were 1.97 (0.95-4.07), 2.22 (1.05-4.68) and 1.29 (1.06-1.57) for bilateral, unilateral and any ear hearing loss, respectively. CONCLUSIONS: Occupational noise exposure is positively associated with both hypertension and bilateral hearing loss among female workers of childbearing age. Those exposed to occupational noise show an increased risk of hypertension after adjusting for potential confounders.

Association between occupational noise and obesity: a retrospective cohort study in China.

OBJECTIVES: To determine the relationship between occupational noise, and obesity and body mass index (BMI) changes. METHODS: Baseline data were collected from participants (n = 1264) who were followed for 6 years in a retrospective study. The noise exposure level (LAeq,8h) was determined by equivalent continuous weighted sound pressure levels using the fixed-point surveillance method for noise monitoring. The cumulative noise exposure (CNE) level was determined using the equal energy formula, which is based on exposure history and level. RESULTS: The incidence of obesity at low (RR = 2.364, 95% CI 1.123-4.739]), medium (RR = 3.921, 95% CI 1.946-7.347]), high (RR = 5.242, 95% CI 2.642-9.208]), and severe noise levels (RR = 9.322, 95% CI 5.341-14.428]) was higher risk than the LAeq,8h control level. The risk of obesity among participants exposed to low (RR = 2.957, 95% CI 1.441-6.068]) and high cumulative noise levels (RR = 7.226, 95% CI 3.623-14.415]) was greater than the CNE control level. For every 1 dB(A) increase in LAeq,8h, the BMI increased by 0.063 kg/m2 (95% CI 0.055-0.071], SE = 0.004). For every 1 dB(A) increase in the CNE, the BMI increased by 0.102 kg/m2 (95% CI 0.090-0.113], SE = 0.006). CONCLUSIONS: Occupational noise is related to the incidence of obesity. The occupational noise level and occupational noise cumulative level were shown to be positively correlated with an increase in BMI.

Comparison of the risk of noise-induced hearing loss between male police officers and male non-police officers: a nationwide cohort study using propensity score matching in South Korea.

BACKGROUND: Police officers are at a high risk of noise-induced hearing loss (NIHL) owing to the nature of their work. Therefore, this study aimed to compare the risk of NIHL in police officers and controls. METHODS: This study used the National Health Insurance claims data of workers aged 25-65 years obtained from 2005 to 2015. The case group comprised police officers, while the control group comprised general workers and public officers. The study followed a three-phase cohort design. The standardized incidence ratio (SIR) was calculated using an indirect standardization method based on age. Propensity score matching was performed using the greedy matching method, with a police officer-to-control group ratio of 1:3. Cox regression analysis was performed for each matched control group. Statistical significance was determined by a lower limit of greater than 1, based on the 95% confidence interval (CI). RESULTS: The SIR values for police officers were 1.62 (95% CI: 1.44-1.82) compared with general workers and 1.78 (95% CI: 1.66-1.73) compared with public officers. Police officers exhibited an increased risk of NIHL compared with general workers (hazard ratio (HR): 1.71, 95% CI: 1.49-1.98) and public officers (HR: 2.19, 95% CI: 1.88-2.56). CONCLUSIONS: It is necessary to prevent NIHL by reducing occupational noise exposure through measures such as wearing earplugs, improving shooting training methods, and improving the shift work system.

Prevalence and predictors of high-frequency hearing loss among mine workers in Gujarat, western India: a cross-sectional study on the need to implement a comprehensive hearing conservation program.

BACKGROUND: High-frequency hearing loss (HFHL) stands as a prevalent occupational morbidity globally, with numerous associated risk factors, some of which are modifiable. In the context of a comprehensive hearing conservation program, the initial steps involve early screening and identification of workers with these modifiable risk factors, aiming to reduce the prevalence of hearing loss. Our objective was to estimate the prevalence of HFHL and determine its predictors among mine workers. METHODS: We conducted a cross-sectional study among 226 mine workers in ten open-cast mines in Gujarat state, the western part of India, in November 2020. We collected data on socio-demography, addiction, occupation history and comorbidities, along with anthropometric, blood pressure, and blood sugar measurements. Audiometric evaluations using a portable diagnostic audiometer were employed to assess HFHL, defined as a hearing threshold exceeding 25 decibels (dB) at high frequencies (3000, 4000, 6000, and 8000 Hz). A generalized linear model (GLM) with a binomial family was performed to determine the predictors significantly predicting HFHL after adjusting for confounding variables. RESULTS: The prevalence of HFHL was 35% (95% CI: 29-42%) in our study setting. Office workers demonstrated a prevalence of 19%, whereas other job categories displayed a higher prevalence of 42%, resulting in a significant prevalence difference of 23% and a prevalence ratio of 2.2. The GLM analysis revealed that variables, such as noise exposure during work [adjusted prevalence ratio (aPR) 2.3 (95% CI: 1.2-4.7, p = 0.018)] and noise exposure duration [aPR 1.1 (95% CI: 1.0-1.1, p = 0.042)], were significant predictors of HFHL. CONCLUSIONS: In our study setting, mine workers exhibited a high prevalence of HFHL, with exposure to workplace noise and duration being modifiable predictors. Because HFHL advances slowly and is generally undetected by the individual, we recommend periodic testing using audiometry to identify it among mine workers and, if possible, shifting them from mining activities to office. Furthermore, we advocate for the implementation of a comprehensive hearing conservation program to the extent possible.

No accelerated 20-year hearing decline after occupational noise exposure has ceased: The HUNT study.

OBJECTIVES: It has been suggested that noise exposure can accelerate hearing decline after the noise exposure has ceased. We aimed to assess long-term hearing decline in persons with and without prior occupational noise exposure. METHODS: We conducted a population-based longitudinal study in Norway using the Trøndelag Health Study (HUNT) from 1996 to 1998 (baseline) and from 2017 to 2019 (follow-up). The sample included 1648 participants with baseline age ≥55 years (42% men, mean age 60 years) and <5 years occupational noise exposure after baseline. We analyzed the association between occupational noise exposure before baseline and mean hearing decline between 1998 and 2018 (20-year decline) at each frequency, adjusted for age, sex, education, and impulse noise exposure before baseline. RESULTS: Occupational noise exposure before baseline (N = 603) was associated with baseline hearing loss, but not with later accelerated 20-year decline, at any frequency. Noise-exposed persons had less subsequent 20-year decline at 3 kHz than did nonexposed. Restricting the noise-exposed group to persons who also had a baseline Coles notch (hearing thresholds at 3, 4, or 6 kHz of 10 dB or more compared with thresholds at 1 or 2 kHz and 6 or 8 kHz; N = 211), the exposed group showed less 20-year decline at both 3 and 4 kHz, as well as less accelerated 20-year decline at 8 kHz, compared with the nonexposed. CONCLUSION: Our large long-term longitudinal study shows no increased risk of continuing hearing decline after occupational noise exposure has ceased. The finding supports a conclusion that ear damage stops when the noise exposure is ended.

Association between occupational noise exposure level and pure-tone audiometry abnormalities among Metropolitan Manila Development Authority employees: A cross-sectional study.

Traffic enforcers are exposed to various occupational health and safety hazards, including noise pollution, which may lead to occupational hearing loss. This cross-sectional study aimed to estimate the prevalence of hearing loss and to assess the relationship between occupational noise exposure level (ONEL) and abnormalities in air conduction thresholds among Metropolitan Manila Development Authority (MMDA) employees along Epifanio delos Santos Avenue, Philippines. Eight-hour ONELs were measured among 108 participants working with greater than 5 years of service. Participants had hearing evaluations using pure tone audiometry (PTA) to calculate the prevalence of hearing loss. Generalized linear models with a Poisson distribution were fitted to estimate the association between ONEL and audiologic abnormalities, controlling for confounding factors. Approximately 16% of employees had hearing loss. The prevalence of hearing loss was higher with ONEL exposures greater than 85 A-weighted decibels (dBA), with traffic enforcers exposed to higher ONELs than office workers. ONELs greater than 85 dBA were related to audiologic abnormalities at different frequencies in PTA. The prevalence of audiologic abnormalities at 4000 Hz and 6000 Hz was 48% higher (adjusted prevalence ratio [aPR], 1.48; 95% CI, 1.12-1.96) and 25% higher (aPR, 1.25; 95% CI, 1.00-1.55), respectively, among participants with ONELs greater than 85 dBA than with ONELs less than or equal to 85 dBA. Participants exposed to ONELs greater than 85 dBA, more likely traffic enforcers, may have increased risk of audiologic abnormalities. Regular ONEL monitoring is warranted for occupational risk assessment of traffic enforcers. A hearing conservation program may need to be considered for this population. Additional studies are needed to determine trends in hearing deterioration among traffic enforcers.

Noise-Induced Hearing Loss and Use of Hearing Protection Awareness among Medical Students in Saudi Arabia: Mixed Qualitative and Quantitative Study.

BACKGROUND: Noise-Induced Hearing Loss (NIHL) is a prevalent occupational hazard among healthcare professionals, including medical students. Despite its detrimental effects, the awareness and utilization of hearing protection measures among medical students in Saudi Arabia remain understudied. OBJECTIVE: Is to determine the level of awareness and understanding of NIHL among medical students in Saudi Arabia, as well as their knowledge and usage of hearing protection measures and to identify potential barriers and facilitators for hearing protection utilization. METHODS: A mixed-methods approach was employed, involving a questionnaire survey and semi-structured interviews. The survey collected data on demographics, knowledge of NIHL, and hearing protection practices among medical students. Subsequently, a semi-structured interview was conducted to obtain in-depth insights into the students' experiences, attitudes, and beliefs regarding NIHL and the use of hearing protection. RESULTS: The level about NIHL was 59.32%. Better access to information is associated with increased odds of awareness (odds ratio=3.07, p=0.012). Having relatives with hearing loss increases the odds of awareness (odds ratio =2.49, p=0.034). Individuals with hearing loss or impairment have higher odds of awareness (odds ratio =2.27, p=0.046). Ear Pain, temporary hearing loss, tinnitus, or ringing in the ear: These factors are not significantly associated with awareness of noise-induced hearing loss (p>0.05). Using hearing aids is strongly associated with increased odds of awareness (odds ratio =3.94, p=0.006).The quantitative analysis provided statistical information on the prevalence rates and factors influencing hearing protection usage, while the qualitative analysis uncover nuanced perspectives and experiences. CONCLUSION: This research will contribute to the understanding of NIHL and hearing protection practices among medical students in Saudi Arabia. Improving hearing protection awareness and practices among medical students can ultimately reduce the incidence of NIHL and promote a healthier work environment within the healthcare sector.

[Quantitative analysis of the characteristics and influencing factors of hearing loss among workers exposed to noise in Tianjin].

Objective: To analyze the characteristics of high-frequency average hearing loss in both ears of noise exposed workers in Tianjin in 2020, and quantitatively analyze the influencing factors of high-frequency hearing loss in both ears of workers. Methods: In March 2023, Collect and organize basic information about noise-hazardous enterprises and personal information of workers exposed to noise. Data from the Tianjin Occupational Disease and Health Hazard Factors Information Monitoring System from January 2020 to December 2020, and analyze the impact of basic information of employees, enterprise size, regional distribution, industry category, and economic type on the high-frequency average hearing loss of workers during work. Apply logistic regression to quantitatively analyze the influencing factors of abnormal high-frequency average hearing threshold of noise exposed workers. Results: The size, economic type, industry category, and regional distribution of enterprises, as well as the gender, age, length of service of workers, have an impact on the abnormal high-frequency average hearing threshold of noise exposed workers (χ(2)=733.56、3 497、27、1352.84、1197.62、2570.59、22.30、506.60, P<0.001) . Quantitative analysis using a logistic regression model showed that in the basic information of workers, noise exposed workers were male (OR=2.500, P<0.001) and aged 30-39, 40-49, and 50-59 years (OR=1.33, P<0.001; OR=1.68, P<0.001; OR=1.52, P< 0.001) , with a length of service of 4 to<10 years and≥10 years (OR=1.08, P<0.001; OR=1.615, P<0.001) being the influencing factors for high-frequency hearing loss in both ears of noise exposed workers; In terms of enterprise characteristics, medium-sized, small and micro enterprises (OR=1.12, P<0.001; OR=1.75, P<0.001; OR=2.09, P<0.001) , enterprises located in the fourth district around the city (OR=1.268, P<0.001) , and enterprises with economic types of collective economy, other economy, private economy, Hong Kong, Macao and Taiwan investment, shareholding system, and other industry economies (OR are all >1, P<0.001) are all factors affecting high-frequency hearing loss in noise exposed personnel. Conclusion: Noise is a common occupational hazard factor in Tianjin's enterprises, especially for workers in micro enterprises who face a high risk of hearing abnormalities. Therefore, enterprises need to strengthen the management and intervention of noise operations to prevent the occurrence of hearing loss in workers.

[Analysis of disease burden and trends of noise-induced hearing loss in China from 1990 to 2019].

Objective: To analyze the disease burden of Noise-Induced Hearing Loss (NIHL) in China from 1990 to 2019, forecast the disease burden of NIHL from 2020 to 2030, and provide data support for the prevention and control of NIHL. Methods: In July 2022, the disease burden data of NIHL in different age groups and genders in China during 1990-2019 were selected from the GBD database. The Jointpoint regression model was established to analyze the trend of the disease burden of NIHL in China. An age-period-cohort model was constructed to analyze the changing trend of NIHL in terms of age, period, and cohort, and a Bayesian age-period-cohort model was developed to predict the disease burden of NIHL in China from 2020 to 2030. Results: From 1990 to 2019, the disability adjusted life year (DALY) of China's NIHL increased from 1361600 to 2327700 years. The coarse rate of DALY increased from 115.03/100000 to 163.65/100000 (AAPC=1.23, P<0.001), and the normalization rate of DALY decreased from 127.67/100000 to 119.83/100000 (AAPC=-0.21, P<0.001). It is predicted that from 2020 to 2030, the DALYs of China's NIHL will increase from 2412900 in 2020 to 2655000 in 2030, and the DALY normalization rate will decrease from 241.29/100000 in 2020 to 125.71/100000 in 2030. Conclusion: The burden of noise-induced hearing loss (NIHL) in China is significant and should not be overlooked. To reduce this burden, we need to focus on strengthening source management, process control, personal protection, and comprehensive prevention and treatment through various methods.

[Study on the fit testing for the workers wearing hearing protection device in machinery manufacturing enterprises].

Objective: To investigate the occupational noise hazards in five machinery manufacturing enterprises, and to evaluate the individual noise reduction values and influencing factors of workers wearing hearing protection device (HPD) by individual fit testing. Methods: From November 2021 to January 2022, 5 machinery manufacturing enterprises in Bao'an District of Shenzhen were selected to conduct an occupational health survey to understand the noise exposure level of workers. The 3MTM E-A-RfitTM fitness test system was used to test the baseline individual sound attenuation value level (PAR) of the daily wear of the ear protecters for 485 workers in typical noise working positions. Workers whose PAR values could not meet the requirements of noise reduction at work were instructed to wear and repeated tests were conducted. PAR results of the workers before and after the intervention were collected and analyzed. Results: The noise workers who received the suitability test were mainly distributed in 24 types of work, the job noise exposure level was 80.2 dB (A) ~ 95.0 dB (A), and the job noise excess rate was 52.5% (138/263). The median baseline PAR [M (Q(1), Q(3)) ] for 485 workers was 6.0 (0.0, 14.0) dB. The baseline PAR of male workers, those with more than 15 years of working experience, those with more than 15 years of using ear guards, those who considered ear guards comfortable to wear, those with college degree or above, and those exposed to noise level 90 dB (A) were higher, and the difference was statistically significant (P<0.05). A total of 275 workers (56.7%) did not pass the baseline PAR test, and there was no statistically significant difference in the intervention rate of workers in different noise groups (P>0.05). PAR in subjects who did not pass baseline after intervention increased from 0.0 (0.0, 3.0) dB to 15.0 (12.0, 18.2) dB. Conclusion: The workplace noise hazard of machinery manufacturing enterprises is serious, and there is a great difference between the baseline PAR and the nominal value of the hearing guard worn by the noise exposed workers. The intervention measures can effectively improve the protective effect of wearing ear protectors.

Effectiveness of Kurtosis-Adjusted Cumulative Noise Exposure in Assessing Occupational Hearing Loss Associated With Complex Noise.

OBJECTIVES: Occupational noise-induced hearing loss (NIHL) is one of the most prevalent occupational diseases worldwide. Few studies have been reported on applying kurtosis-adjusted noise energy (e.g., kurtosis-adjusted cumulative noise exposure, CNE-K) as a joint indicator for assessing NIHL. This study aimed to analyze the effectiveness of CNE-K in assessing occupational hearing loss associated with complex noise in typical manufacturing industries. DESIGN: A cross-sectional survey of 1404 Chinese manufacturing workers from typical manufacturing industries was conducted. General demographic characteristics, noise exposure data, and noise-induced permanent threshold shifts (NIPTS) at 3, 4, and 6 kHz (NIPTS 346 ) were collected and analyzed. The role of kurtosis in high-frequency noise-induced hearing loss (HFNIHL) was also analyzed. The degree of overlap of the two logistic curves (i.e., between complex noise CNE-K and HFNIHL%, and between Gaussian noise CNE and HFNIHL%) was used to evaluate the effectiveness of CNE-K, using a stratified analysis based on age, sex, industry, or job type. RESULTS: The binary logistic regression analysis showed that in addition to age, sex, exposure duration, and Eight-hour Continuous Equivalent A-weighted Sound Pressure Level (L Aeq,8h ), kurtosis was a key factor influencing HFNIHL% in workers (odds ratio = 1.18, p < 0.05), and its odds ratio increased with an increase in kurtosis value. Multiple linear regression analysis demonstrated that the contribution of kurtosis to NIPTS 346 was second to L Aeq,8h . Complex noise led to a higher risk of NIHL than Gaussian noise at frequencies of 3, 4, 6, and 8 kHz after adjusting for age, sex, and CNE ( p < 0.05). As kurtosis increased, the notch in the audiogram became deeper, and the frequency at which the notch began to deepen shifted from 3 to 1 kHz. The logistic curve between complex noise CNE-K and HFNIHL% nearly overlapped with that between Gaussian noise CNE and HFNIHL%, and the average difference in HFNIHL% between the two curves decreased from 8.1 to 0.4%. Moreover, the decrease of average difference in HFNIHL% between the two logistic curves was evident in several subgroups, such as male workers, aged <30 and 30 to 50 years, furniture and woodworking industries and gunning and nailing job types with relatively high kurtosis values. CONCLUSIONS: Kurtosis, as an indirect metric of noise temporal structure, was an important risk factor for occupational NIHL. Kurtosis-adjusted CNE metric could be more effective than CNE alone in assessing occupational hearing loss risk associated with complex noise.

Community Perspectives on Hearing Loss in Rural Alaska.

OBJECTIVES: The aim of this study is to present an explanatory model of hearing loss in the Bering Strait region of Alaska in order to contextualize the results of a cluster randomized trial and propose implications for regional hearing-related health care. DESIGN: To promote ecological validity, or the generalizability of trial findings to real world experiences, qualitative methods (focus groups and interviews) were used within a mixed methods cluster randomized trial evaluating school hearing screening and follow-up processes in 15 communities in the Bering Strait region of Alaska. Focus groups were held between April and August 2017, and semistructured interviews were conducted between December 2018 and August 2019. Convenience sampling was used for six of the 11 focus groups to capture broad community feedback. Purposive sampling was used for the remaining five focus groups and for all interviews to capture a variety of experiences with hearing loss. Audio recordings of focus groups and interviews were transcribed, and both notes and transcripts were deidentified. All notes and transcripts were included in the analysis. The constant comparative method was used to develop a codebook by iteratively moving between transcripts and preliminary themes. Researchers then used this codebook to code data from all focus groups and interviews using qualitative analysis software (NVIVO 12, QSR International) and conducted thematic analyses to distill the findings presented in this article. RESULTS: Participants in focus groups (n = 116) and interviews (n = 101) shared perspectives in three domains: etiology, impact, and treatment of hearing loss. Regarding etiology, participants emphasized noise-induced hearing loss but also discussed infection-related hearing loss and various causes of ear infections. Participants described the impact of hearing loss on subsistence activities, while also detailing social, academic, and economic consequences. Participants described burdensome treatment pathways that are repetitive and often travel and time intensive. Communication breakdowns within these pathways were also described. Some participants spoke positively of increased access via onsite hearing health care services in "field clinics" as well as via telemedicine services. Others described weaknesses in these processes (infrequent field clinics and communication delays in telemedicine care pathways). Participants also described home remedies and stigma surrounding the treatment for hearing loss. CONCLUSIONS: Patient-centered health care requires an understanding of context. Explanatory models of illness are context-specific ways in which patients and their networks perceive and describe the experience of an illness or disability. In this study, we documented explanatory models of hearing loss to foster ecological validity and better understand the relevance of research findings to real-life hearing-related experiences. These findings suggest several areas that should be addressed in future implementation of hearing health care interventions elsewhere in rural Alaska, including management of repetitious treatments, awareness of infection-mediated hearing loss, mistrust, and communication breakdowns. For hearing-related health care in this region, these findings suggest localized recommendations for approaches for prevention and treatment. For community-based hearing research, this study offers an example of how qualitative methods can be used to generate ecologically valid (i.e., contextually grounded) findings.

Hearing loss and respiratory health symptoms among large-scale sawmill workers of the timber processing factories within the Gert Sibande District Municipality: a comparative cross-sectional study.

BACKGROUND: Occupational exposure to wood dust may cause respiratory illnesses, while prolonged exposure to loud noise may cause noise-induced hearing loss. OBJECTIVE: The objective of the study was to assess the prevalence of hearing loss and respiratory symptoms among large-scale sawmill workers within the Gert Sibande Municipality in Mpumalanga Province, South Africa. METHODS: A comparative cross-sectional study consisting of 137 exposed and 20 unexposed randomly selected workers was undertaken from January to March 2021. The respondents completed a semi-structured questionnaire on hearing loss and respiratory health symptoms. DATA ANALYSE: The data was analysed using Statistical Package for Social Sciences (SPSS) version 21 (Chicago II, USA). The statistical analysis of the difference between the two proportions was done using an independent student t-test. The level of significance was set at p < 0.05. RESULTS: There was a statistically significant difference between the exposed and unexposed workers on the prevalence of respiratory symptoms like phlegm (51.8 vs. 0.0%) and shortness of breath (chest pain) (48.2 vs. 50%). There was also a statistically significant difference between the exposed and unexposed workers on the signs and symptoms of hearing loss like tinnitus (ringing in the ears) (50 vs. 33.3%), ear infections (21.4 vs. 66.7%), ruptured ear drums (16.7 vs. 0.0%), and ear injuries (11.9 vs. 0.0%). The exposed workers reported always wearing personal protective equipment (PPE) (86.9%) compared to the unexposed workers (75%). The reason for not wearing PPE consistently by the exposed workers was due to not being available (48.5%), compared to the unexposed workers who reported other reasons (100%). CONCLUSION: The prevalence of respiratory symptoms among the exposed workers was higher than that of the unexposed workers, except for chest pains (shortness of breath). The prevalence of symptoms of hearing loss among the exposed workers was higher than the unexposed workers, except for ear infections. The results suggest that measures should be implemented at the sawmill to help protect workers' health.

The rate of occupational noise-induced hearing loss among male workers in Israel and implication on hearing surveillance frequency.

OBJECTIVES: To investigate the annual rate of NIHL in Israel, a modern economy with relatively low industrial hazardous noise exposure. To review international protocols of hearing surveillance. To recommend an effective, efficient, hearing screening frequency protocol. METHODS: A historical cohort study was conducted. Audiometric surveillance data from the Jerusalem occupational medicine registry of male employees in various industries from 2006 to 2017 were used. Mean individual annual threshold shifts simulating 1-8 checkup interval years were calculated. Joinpoint regression analysis was used to assess the interval in which the slope of the calculated ATS variability moderates significantly. RESULTS: A total of 263 noise-exposed workers and 93 workers in the comparison group produced 1913 audiograms for analysis. Among the noise-exposed workers, using the 1-4 kHz average, threshold shifts stabilized from 3 years onwards at around 1 dB per year in all age groups and 0.83 dB in the stratum younger than 50 years. No enhanced decline was detected in the first years of exposure. CONCLUSION: Although most countries conduct annual hearing surveillance, hearing threshold shifts of noise-exposed workers become more accurate and show less variability when calculated at 3-year checkup intervals onwards than shorter intervals. Since margins of errors of the test method are much larger than the annual shift found, screening schedule that enables each subsequent test to identify a real deterioration in hearing is necessary. Triennial audiometric screening would be a better surveillance frequency for noise-exposed workers younger than 50 years of age in the category of 85-95 dBLAeq,8 h without other known risk factors.

Investigation of critical factors influencing the underestimation of hearing loss predicted by the ISO 1999 predicting model.

OBJECTIVE: To analyze factors influencing the underestimation of noise-induced permanent threshold shift (NIPTS) among manufacturing workers, providing baseline data for revising noise exposure standard. DESIGN: A cross-sectional study was designed with 2702 noise-exposed workers from 35 enterprises from 10 industries. Personal noise exposure level(LAeq,8h) and noise kurtosis level were determined by a noise dosimeter. Questionnaires and hearing loss tests were performed for each subject. The predicted NIPTS was calculated using the ISO 1999:2013 model for each participant, and the actual measured NIPTS was corrected for age and sex. The factors influencing the underestimation of NIPTS were investigated. RESULTS: The predicted NIPTS at each test frequency (0.5, 1, 2, 3, 4, or 6kHz) and mean NIPTS at 2, 3, 4, and 6kHz (NIPTS2346) using the ISO 1999:2013 model were significantly lower than their corresponding measured NIPTS, respectively (P < 0.001). The ISO model significantly underestimated the NIPTS2346 by 12.36 dB HL. The multiple linear regression analysis showed that noise exposure level, exposure duration, age, and kurtosis could affect the degree of underestimation of NIPTS2346. The generalized additive model (GAM) with (penalized) spline components showed nonlinear relationships between critical factors (age, exposure duration, noise level, and kurtosis) and the underestimated NIPTS2346.The underestimated NIPTS2346 decreased with an increase in exposure duration (especially over ten years). There was no apparent trend in the underestimated NIPTS2346 with age. The underestimated NIPTS2346 decreased with the increased noise level [especially > 90 dB(A)]. The underestimated NIPTS2346 increased with an increase in noise kurtosis after adjusting for the noise exposure level and exposure duration and ultimately exhibiting a linear regression relationship. CONCLUSIONS: The ISO 1999 predicting model significantly underestimated the noise-induced hearing loss among manufacturing workers. The degree of underestimation became more significant at the noise exposure condition of fewer than ten years, less than 90 dB(A), and higher kurtosis levels. It is necessary to apply kurtosis to adjust the underestimation of hearing loss and consider the applying condition of noise energy metrics when using the ISO predicting model.

Noise-induced hearing loss profile among Taiwan Airforce on duty pilots.

PURPOSE: Noise-induced hearing loss (NIHL) often results in impaired functional hearing and accidental injuries; thus, reducing military performance and endangering flight safety. While a few studies addressing laterality (left-right ear differences) and NIHL incidence between fixed-winged (jet-fighter) and rotary-wing (helicopter) aircrafts yielded inconsistent results, little is known about the NIHL profile among different types of jet-fighter pilots. This study aims to conduct a fine-grained examination of NIHL among Airforce jet pilots, with planned comparisons of laterality and aircraft type, along with the goal to compare the sensitivity of different hearing indices in predicting military pilot NIHL. MATERIALS AND METHODS: This cross-sectional study utilizes the health and hearing data of 1025 Taiwanese Air Force Military pilots from the 2019 Taiwanese physical examination database to assess the changes in their hearing thresholds, and evaluate their risk for NIHL. RESULTS: Our results showed that, among available military aircraft types, the trainer aircraft and M2000-5 jet-fighter had the highest risk of NIHL, in addition to a left ear inferiority found in the overall population of military pilots. Among the three hearing indices used in this study -the International Organization for Standardization (ISO) three-point hearing index, the Occupational Safety and Health Administration (OSHA) three-point hearing index, and the American Academy of Otolaryngology-Head and Neck Surgery's (AAO-HNS) high-frequency three-point hearing index-, the OSHA the AAO-HNS were the most sensitive. CONCLUSION: Our results suggest a better noise protection for trainer and M2000-5 pilots, especially for the left ear, is warranted.

Noise exposure in pediatric otolaryngology clinic: A sound survey of a single-institution tertiary care facility.

BACKGROUND: The Occupational Safety and Health Administration (OSHA) considers acoustic exposure of 90 decibels (dB) an occupational risk for noise-induced hearing loss. Pediatric healthcare clinicians are exposed to considerable noise especially during invasive procedures, predisposing them to noise-induced hearing loss, increased work-related stress, and increased complications associated with intense noise exposure. While there has been extensive research in noise exposure in dentistry, to date there has been no research on noise exposure in the pediatric otolaryngology clinic setting. The objective of this study is to quantify the degree of noise exposure that pediatric otolaryngologists encounter in the clinical setting. METHODS: A sound survey was performed of 420 pediatric otolaryngology clinic visits within a single-institution tertiary care facility from January 2022 to March 2022, with a total of 409 visits included. At each visit, noise was measured using a calibrated National Institute for Occupational Safety and Health (NIOSH) Sound Meter application, an iPad, and a microphone. The Equivalent Continuous Sound Pressure Level (LAeq), peak sound pressure level (SPL), C-weighted peak noise level (LCpeak), and the 8-hour time-weighted average (TWA) sound level were recorded. RESULTS: The average LAeq was 61.1 dB, the median LAeq was 60.3 dB, and the average peak SPL was 80.5 dB. Only 0.5 % of visits reached an LAeq above 80 dB, however, 51 % were above 60 dB and 99 % were above 45 dB. No clinicians were exposed to noise exceeding established limits of safety. Patients younger than ten years old (p < 0.001) and those who underwent procedures such as cerumen removal (p < 0.001) elicited higher ranges of elevated noise. Multivariate analysis confirmed that increased age decreased acoustic exposure while procedures increased acoustic exposure. CONCLUSIONS: The results of this study suggest that pediatric otolaryngology clinicians do not exceed hazardous noise limit exposure. However, they are exposed to levels above those which have been linked to stress, poor productivity, and stress-related disorders. This analysis also reports that patients who are younger and those that undergo procedures, specifically cerumen removal, tend to expose their providers to the highest levels of noise. This is the first study examining noise exposure in pediatric otolaryngology, and further research should evaluate the risks of noise exposure in this environment.

The relationship between hearing status, listening effort, and the need for recovery in employees of a manufacturing company.

OBJECTIVE: Hearing screening can be used to detect hearing loss, but its value for identifying employees with work functioning difficulties is unclear. The objective of this study was to assess the association between the hearing status measured with an occupational hearing-in-noise screening test, Listening Effort (LE), and Need For Recovery (NFR) in employees of a manufacturing company, and to examine whether these associations depend on the perceived noise level at the workplace. METHODS: Employees of coatings and paints manufacturing company were included. Their hearing status was assessed with an occupational hearing-in-noise screening test. An online survey was used to assess their LE, NFR, and the perceived noise level at the workplace. Responses from 143 employees were analyzed (mean age = 53 years) using hierarchical multiple regression analysis with the outcomes LE and NFR. RESULTS: Regression analysis-with adjustments for gender, age, educational level, health status, pace/amount of work, job variety, and work pleasure-revealed that hearing status was significantly associated with LE, but the interaction between hearing status and the perceived noise level was not. Hearing status nor the interaction between hearing status and the perceived noise level was significantly associated with NFR. CONCLUSION: The results confirm that poorer hearing is associated with higher LE, but not with higher NFR. These associations were unrelated to the perceived noise level at the workplace. Therefore, the value of occupational hearing screening appears to be early identification of hearing loss in employees, but not identification of work functioning difficulties.

Re-estimated normal hearing threshold levels for pure tones using the calculation procedure of ISO 7029:2017.

OBJECTIVE: The objectives of this study were (1) to re-calculate hearing threshold levels (HTLs) for pure tones as described in an international standard, ISO 7029:2017, and (2) to explain the procedure of how HTLs in the standard had been derived. DESIGN: Pure-tone hearing threshold data used for developing ISO 7029:2017 and additional data sets were combined to re-estimate median HTLs and the distribution of individual HTLs around the median. The calculation was done for audiometric frequencies from 125 Hz to 8000 Hz and extended high frequencies from 9000 Hz to 12,500 Hz for ages from 18 to 80 years. STUDY SAMPLE: Approximately 9000 men and 20,000 women employed in 15 studies in nine countries. They had been rigorously screened for hearing abnormalities. RESULTS: A new set of median HTLs and distribution around the median was obtained as a function of age for males and females separately and compared with the estimates in ISO 7029. The differences among these threshold values were discussed. CONCLUSIONS: The calculation procedure described would help understand how the normative HTLs in ISO 7029:2017 had been obtained. Re-calculated HTLs could serve as a basis for the next edition of the standard that covers a wider range of population.