Trends in the Prevalence of Hearing Loss Among Young Adults Entering An Industrial Workforce 1985 to 2004

Evaluating the Accuracy of Android Applications in Monitoring Environmental Noise Levels

Objective This study aimed to evaluate the accuracy of Android applications (apps) in measuring environmental noise levels, focusing on their potential use for occupational health assessments. Methods The top 10, highly rated, free Android apps were tested on a Samsung Galaxy A54 Smartphone (Samsung Group, Samsung Town, Seoul, South Korea) using pure tones at 100 Hz, 2000 Hz, and 4000 Hz, across four noise levels (25 dB, 40 dB, and 85 dB). Measurements were compared with a calibrated Precision Gold N09AQ environment meter (Maplin Electronics Ltd, Wath-Upon-Dearne, United Kingdom) in a controlled room. Data were analyzed using linear regression to determine R2 values for each app. Results The control meter showed the highest accuracy (R2 = 0.99). SPL Meter dB and sound Meter (KTW apps, Petaling Jaya, Selangor, Malaysia) and Sound Meter (Pony AI Inc.,Guangzhou, Guangdong, China) had the best performance (R2 = 0.98). Accuracy declined at higher noise levels, with Sound Meter (ABC Apps) showing the least accuracy (R2 = 0.85). User ratings did not correlate consistently with app performance. Conclusion Android apps offer potential as affordable noise measurement tools, with some apps demonstrating high accuracy at lower decibels. However, limitations such as reduced accuracy at higher decibels and lack of A-weighting for regulatory compliance hinder their use in professional settings. Further development and real-world testing are needed.

Prevalence of hearing loss in college students: a meta-analysis

Introduction

Hearing loss among college students, specifically noise-induced hearing loss (NIHL), appears to be increasing. This may be particularly challenging for this population as college students are required to listen to lectures in classrooms that may have suboptimal listening environments. College-aged musicians are at a particularly high risk due to repeated and extended exposure to loud noise. Therefore, the purpose of the current study was (1) to examine the prevalence of hearing loss in college students and (2) to emphasize the importance of detecting hearing loss at 6,000 Hz.

Methods

A meta-analysis was conducted using the PRISMA model. The literature search yielded 8 studies (1,950 subjects) that tested hearing loss using an audiogram and Distortion Product Otoacoustic Emissions (DPOAEs). All studies used audiologic tests to detect hearing loss among college students between the ages of 17-35 years.

Results

Results indicate that the prevalence of hearing loss in college students is 19%. In addition, the prevalence of hearing loss at 6,000 Hz is 85% among student musicians. For this meta-analysis, slight sensorineural hearing loss, or thresholds greater than 20 dB bilaterally or unilaterally, qualified as hearing loss.

Discussion

Decreased hearing at 6,000 Hz may lead to an individual's inability to hear important environmental factors and high frequency speech sounds. College students without full auditory function at this frequency may have difficulties performing in class based on decreased attention, comprehension, and memory. Although students may not realize the influence of their 6,000 Hz hearing loss or be unaware of its presence, it could significantly change their likelihood to succeed in college. Therefore, implementing a hearing conservation program may be advised for colleges and universities to help prevent hearing loss in students, particularly for collegiate musicians. In addition, it may be beneficial to screen hearing in college students at 6,000 Hz for better detection of hearing loss overall.

Leisure noise exposure and hearing outcomes among Canadians aged 6 to 79 years

OBJECTIVE

To examine the association between individual and cumulative leisure noise exposure in addition to acceptable yearly exposure (AYE) and hearing outcomes among a nationally representative sample of Canadians.

DESIGN

Audiometry, distortion-product otoacoustic emissions (DPOAEs) and in-person questionnaires were used to evaluate hearing and leisure noise exposure across age, sex, and household income/education level. High-risk cumulative leisure noise exposure was defined as 85 dBA or greater for 40 h or more per week, with AYE calculations also based on this occupational limit.

STUDY SAMPLE

A randomised sample of 10,460 respondents, aged 6-79, completed questionnaires and hearing evaluations between 2012 and 2015.

RESULTS

Among 50-79 year olds, high-risk cumulative leisure noise was associated with increased odds of a notch while high exposure to farming/construction equipment noise was associated with hearing loss, notches and absent DPOAEs. No associations with hearing loss were found however, non-significant tendencies observed included higher mean hearing thresholds, notches and hearing loss odds.

CONCLUSION

Educational outreach and monitoring of hearing among young and middle-aged populations exposed to hazardous leisure noise would be beneficial.

Preventing Excessive Noise Exposure in Infants, Children, and Adolescents

Noise exposure is a major cause of hearing loss in adults. Yet, noise affects people of all ages, and noise-induced hearing loss is also a problem for young people. Sensorineural hearing loss caused by noise and other toxic exposures is usually irreversible. Environmental noise, such as traffic noise, can affect learning, physiologic parameters, and quality of life. Children and adolescents have unique vulnerabilities to noise. Children may be exposed beginning in NICUs and well-baby nurseries, at home, at school, in their neighborhoods, and in recreational settings. Personal listening devices are increasingly used, even by small children. Infants and young children cannot remove themselves from noisy situations and must rely on adults to do so, children may not recognize hazardous noise exposures, and teenagers generally do not understand the consequences of high exposure to music from personal listening devices or attending concerts and dances. Environmental noise exposure has disproportionate effects on underserved communities. In this report and the accompanying policy statement, common sources of noise and effects on hearing at different life stages are reviewed. Noise-abatement interventions in various settings are discussed. Because noise exposure often starts in infancy and its effects result mainly from cumulative exposure to loud noise over long periods of time, more attention is needed to its presence in everyday activities starting early in life. Listening to music and attending dances, concerts, and celebratory and other events are sources of joy, pleasure, and relaxation for many people. These situations, however, often result in potentially harmful noise exposures. Pediatricians can potentially lessen exposures, including promotion of safer listening, by raising awareness in parents, children, and teenagers. Noise exposure is underrecognized as a serious public health issue in the United States, with exposure limits enforceable only in workplaces and not for the general public, including children and adolescents. Greater awareness of noise hazards is needed at a societal level.

Cross-species experiments reveal widespread cochlear neural damage in normal hearing

Animal models suggest that cochlear afferent nerve endings may be more vulnerable than sensory hair cells to damage from acoustic overexposure and aging. Because neural degeneration without hair-cell loss cannot be detected in standard clinical audiometry, whether such damage occurs in humans is hotly debated. Here, we address this debate through co-ordinated experiments in at-risk humans and a wild-type chinchilla model. Cochlear neuropathy leads to large and sustained reductions of the wideband middle-ear muscle reflex in chinchillas. Analogously, human wideband reflex measures revealed distinct damage patterns in middle age, and in young individuals with histories of high acoustic exposure. Analysis of an independent large public dataset and additional measurements using clinical equipment corroborated the patterns revealed by our targeted cross-species experiments. Taken together, our results suggest that cochlear neural damage is widespread even in populations with clinically normal hearing.

Cross-species experiments on chinchillas and at-risk humans suggest cochlear synaptopathy from noise exposure and aging are widespread even among individuals with clinically normal hearing status.

Toward a better understanding of nonoccupational sound exposures and associated health impacts: Methods of the Apple Hearing Study

Globally, noise exposure from occupational and nonoccupational sources is common, and, as a result, noise-induced hearing loss affects tens of millions of people. Occupational noise exposures have been studied and regulated for decades, but nonoccupational sound exposures are not well understood. The nationwide Apple Hearing Study, launched using the Apple research app in November 2019 (Apple Inc., Cupertino, CA), is characterizing the levels at which participants listen to headphone audio content, as well as their listening habits. This paper describes the methods of the study, which collects data from several types of hearing tests and uses the Apple Watch noise app to measure environmental sound levels and cardiovascular metrics. Participants, all of whom have consented to participate and share their data, have already contributed nearly 300 × 10⁶ h of sound measurements and 200 000 hearing assessments. The preliminary results indicate that environmental sound levels have been higher, on average, than headphone audio, about 10% of the participants have a diagnosed hearing loss, and nearly 20% of the participants have hearing difficulty. The study's analyses will promote understanding of the overall exposures to sound and associated impacts on hearing and cardiovascular health. This study also demonstrates the feasibility of collecting clinically relevant exposure and health data outside of traditional research settings.

Awareness about the relation of noise induced hearing loss and use of headphones at Hail region

Background

Noise induced hearing loss is the one of the most preventable causes of hearing loss in all age groups. Occupational, environmental, infectious and genetic factors all play a role in determining the level of hearing loss. However, the use of headphones and personal listening devices is now very common, especially in younger generations. Healthy habits are needed to prevent them from developing hearing loss over time. We aim to assess the awareness level of hearing loss among residents of Hail region and its relation to personal listening devices.

Methodology

This is a cross-sectional survey based study that was conducted in 2021 over a duration of four months. The survey purpose was to assess the level of awareness about the Relation of Noise-Induced Hearing Loss and Use of Headphones. The questionnaire had a total of 37 questions which were divided into 6 categories. All data was analyzed using SPSS 21, and a p-value of <0.05 was deemed significant.

Results

The study included a total of 1086 participants. Sampled population age ranged from 18 to 55 years with a mean age of 24.8 ± 12.6 years old. Meanwhile, 636 (58.6%) of the participants were females and 1074 (98.9%) were Saudi. Hearing problems were significantly higher among those who were exposed to noise at work setting than others (26% vs. 15.9%, respectively; P = .001). Duration of the listening session/per day for more than 5 h was significantly associated with higher rates of hearing problems among participants (33.9% vs. 16.5%, respectively = .001). Typical level of TV or radio volume of 90–100 was associated with hearing problems among 32% compared to 11.2% for 0–49% (P = .001).

Conclusion

There is a low awareness level of hearing loss and its causes among the population with more than half of the respondent having unhealthy habits in listening to sounds through their personal devices. Factors related to develop hearing loss included age, volume level and duration of weekly sessions.

•

Hearing loss prevalence rate has been increasing in the past decade.

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The most common preventable type of hearing loss is noise-induced hearing loss.

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Young generations are more exposed to noises due to increase use of headphones, headsets and other devices.

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Assessing the awareness of hearing loss and its relation to the personal listening devices using pattern is beneficial to reduce rates of noise-induced hearing loss.

Listening Effort Measured Using a Dual-task Paradigm in Adults With Different Amounts of Noise Exposure

OBJECTIVES

Excessive noise levels can result in hearing damage and/or hearing-related symptoms, thereby leading to impaired communication and, eventually a decrease in the quality of life. Moreover, in daily practice, subjects often indicate that listening in noisy situations is a challenging and often exhausting experience, even in the absence of a clinically significant hearing loss. Hence, a person's perceived difficulty of the listening situation will also be important to consider. It has been suggested that beyond the peripheral factors, there are some central cognitive correlates of speech understanding that are essential for communication abilities. The aim of the present study was to evaluate the effect of the amount of noise exposure on hearing as measured by pure-tone audiometry and otoacoustic emissions (OAEs) on the one hand and listening effort measured using a dual-task paradigm on the other hand.

DESIGN

The study included 152 adults between 18 and 40 years of age. First, participants completed a self-administered questionnaire regarding the amount of noise exposure. Second, hearing status was evaluated using pure-tone audiometry and transient evoked OAEs (TEOAEs) as well as distortion product OAEs (DPOAEs). Finally, listening effort was evaluated using a dual-task paradigm, which consisted of a primary speech-recognition task in different listening conditions and a secondary visual memory task that were performed both separately and simultaneously. Based on the quartiles of their subjective estimation of noise exposure, the participants were categorized into a group with low noise exposure (lower quartile), moderate noise exposure (two middle quartiles), and high noise exposure (upper quartile).

RESULTS

There was no significant difference in hearing thresholds between the participants with low, moderate, and high noise exposure for each frequency of the pure-tone audiometry. In contrast, more absent TEOAEs and DPOAEs were found in the high noise exposed group. Regarding the primary speech-recognition task of the dual-task paradigm, no significant difference in speech recognition was found between the different groups of noise exposure. For the amount of listening effort, it was found that across all listening conditions subjects with high noise exposure expend significantly more listening effort compared with subjects with low and moderate noise exposure.

CONCLUSIONS

This study is a first exploration of the effects of different amounts of noise exposure on listening effort showing that, listening effort is increased in subjects with high noise exposure compared with subjects with low and medium noise exposure. The most plausible hypothesis pertains to an effect of noise exposure on the peripheral and central auditory system, or a combination of effects on both the auditory system and the high-level cognitive functions necessary for speech understanding in the subjects with high levels of noise exposure. As such, a test for listening effort would be useful as part of a comprehensive test battery within the assessment of subjects exposed to noise.

Hearing threshold levels of Australian coal mine workers: a retrospective cross-sectional study of 64196 audiograms

OBJECTIVE

This study examined the hearing threshold levels (HTL) of workers commencing employment in Australian coal mines in the State of New South Wales (NSW). The aim was to establish if some degree of hearing loss was identifiable in the mandatory pre-employment audiograms of workers.

DESIGN

This was an observational, retrospective, repeated cross-sectional study.

STUDY SAMPLE

De-identified audiometric records of 64196 employees entering NSW coal mining in three representative five-year periods between 1991-2015 were utilised.

RESULTS

Although HTLs were lower (better) in more recent years, the results showed clinically significant hearing loss (≥25dBHL) for older workers, 45-60 years. Pure tone average (PTA) hearing losses were greater at the higher frequencies associated with excessive noise exposure (3-6 kHz), than at the speech frequencies (0.5-4 kHz). Hearing loss in the left ears were higher compared to the right ears, with higher prevalence of audiometric notches in males.

CONCLUSION

Almost a fifth (14.8-20.1%) of male workers commencing work in NSW coal mines presented with an audiometric notch at 4 kHz. Further research is required to determine if these notches represent true NIHL, and how the residual hearing of workers may be conserved.

Better Hearing in Norway: A Comparison of Two HUNT Cohorts 20 Years Apart

OBJECTIVE

To obtain updated robust data on a age-specific prevalence of hearing loss in Norway and determine whether more recent birth cohorts have better hearing compared with earlier birth cohorts.

DESIGN

Cross-sectional analyzes of Norwegian representative demographic and audiometric data from the Nord-Trøndelag Health Study (HUNT)-HUNT2 Hearing (1996-1998) and HUNT4 Hearing (2017-2019), with the following distribution: HUNT2 Hearing (N=50,277, 53% women, aged 20 to 101 years, mean = 50.1, standard deviation = 16.9); HUNT4 Hearing (N=28,339, 56% women, aged 19 to 100 years, mean = 53.2, standard deviation = 16.9). Pure-tone hearing thresholds were estimated using linear and quantile regressions with age and cohort as explanatory variables. Prevalences were estimated using logistic regression models for different severities of hearing loss averaged over 0.5, 1, 2, and 4 kHz in the better ear (BE PTA4). We also estimated prevalences at the population-level of Norway in 1997 and 2018.

RESULTS

Disabling hearing loss (BE PTA4 ≥ 35 dB) was less prevalent in the more recent born cohort at all ages in both men and women (p < 0.0001), with the largest absolute decrease at age 75 in men and at age 85 in women. The age- and sex-adjusted prevalence of disabling hearing loss was 7.7% (95% confidence interval [CI] 7.5 to 7.9) and 5.3% (95% CI 5.0 to 5.5) in HUNT2 and HUNT4, respectively. Hearing thresholds were better in the more recent born cohorts at all frequencies for both men and women (p < 0.0001), with the largest improvement at high frequencies in more recent born 60- to 70-year old men (10 to 11 dB at 3 to 4 kHz), and at low frequencies among the oldest.

CONCLUSIONS

The age- and sex-specific prevalence of hearing impairment has decreased in Norway from 1996-1998 to 2017-2019.

Noise exposure limit for children in recreational settings: Review of available evidence

It is universally recognized that prolonged exposure to high levels of non-impulsive noise will lead to noise-induced hearing loss. These high levels of noise have traditionally been found in an occupational setting, but exposure to high levels of noise is increasingly common in recreational settings. There is currently no established acceptable risk of hearing loss in children. This review assumed that the most appropriate exposure limit for recreational noise exposure in children would be developed to protect 99% of children from hearing loss exceeding 5 dB at the 4 kHz audiometric test frequency after 18 years of noise exposure. Using the ISO 1999:2013 model for predicting hearing loss, it was estimated that noise exposure equivalent to an 8-h average exposure (L_EX) of 82 dBA would result in about 4.2 dB or less of hearing loss in 99% of children after 18 years of exposure. The 8-h L_EX was reduced to 80 dB to include a 2 dB margin of safety. This 8-h L_EX of 80 dBA is estimated to result in 2.1 dB or less of hearing loss in 99% of children after 18 years of exposure. This is equivalent to 75 dBA as a 24-h equivalent continuous average sound level.

Risk of noise-induced hearing loss due to recreational sound: Review and recommendations

This review was conducted to address three questions related to recreational sound exposure: (1) what criteria are used to determine noise exposure limits, (2) are there differences in the risk of hearing loss from occupational noise versus recreational sound, and (3) what is an appropriate exposure limit for recreational sound? For the first question, most standards specify an 8-h occupational noise exposure limit (L_EX) of 85 dBA. This limit assumes that some workers exposed at the limit will develop hearing loss. To eliminate the risk of hearing loss, a 24-h equivalent continuous level (L_EQ24h) limit of 70 dBA is appropriate. For the second question, there is some evidence that the effects of occupational noise on hearing may be worse than energetically equivalent recreational sound. Limits developed for noise are nevertheless applicable to recreational sound, and use of existing statistical models to predict hearing loss from recreational sound is appropriate, with the caveat that these models are limited to durations ≤40 years. For the third question, a recreational sound limit of 80 dBA L_EX, equivalent to a 75 dBA L_EQ24h, will virtually eliminate the risk of recreationally induced hearing loss in adults. Lower limits may be warranted for vulnerable or susceptible individuals.

Prevalence of loud leisure noise activities among a representative sample of Canadians aged 6-79 years

This population-based study estimates the prevalence of loud leisure noise exposure and hearing protection usage among Canadians, as well as the population potentially at-risk using an occupational limit of 85 dBA, LEX 40 h, which denotes a typical occupational noise limit for a 40 hour work week. A total of 10 460 participants, aged 6-79 years, completed a Canadian Health Measures Survey household questionnaire. Loud leisure noise was defined by vocal effort required while communicating at arm's length except for loud personal listening device (PLD) usage with earbuds/headphones, which included both volume setting and vocal effort. The most prevalent loud leisure noise activities were amplified music, car/home stereo listening, and power tools, with 40% reporting each source, followed by sporting/entertainment (25%), gasoline engines (23%), and loud PLD listening (19.5%). Loud leisure noise was more prevalent among 12-39 year olds and males. Hearing protection usage was uncommon, from 44.2% (firearms) to 20.3% (power tools) and below 3% during amplified music and sporting/entertainment events. Calculations using self-reported duration of loud leisure noise activities estimated that 6.6 × 10⁶ Canadians were in the high cumulative noise exposure category. A large proportion of Canadians would be expected to develop some degree of noise-induced hearing loss should this pattern persist over years.

The test-retest reliability of questionnaires regarding attitudes and beliefs toward noise, hearing loss, and hearing protector devices in young adults

Context:

Young people expose themselves to high noise levels during leisure activities, and might thus be at risk of acquiring hearing-related problems. Therefore, information regarding risk-taking behavior is necessary to prevent future hearing problems and to optimize future preventive campaigns.

Aim:

This study evaluated the test–retest reliability of the Youth Attitude to Noise Scale (YANS) and beliefs about hearing protection and hearing loss (BAHPHL) instrument.

Settings and Design:

Forty-three young adults between 18 and 29 years filled in a questionnaire at two test moments.

Materials and Methods:

The YANS and BAHPHL instrument were used to evaluate the attitudes toward noise, hearing loss, and hearing protection. Each participant completed the retest within 21–55 days after the first administration of the questionnaire.

Results:

Paired Student’s t-tests showed no significant differences in mean scores between test and retest for both the entire YANS and BAHPHL instrument as well as their factors. Furthermore, a good agreement between test and retest scores was seen by Bland–Altman analyses. Intraclass correlation coefficients were above 0.70 for the entire YANS and the factor related to youth culture as well as for the entire BAHPHL and all the factors of the BAHPHL instrument, except for the factor related to the severity of the consequences of hearing loss.

Conclusion:

Reliable test–retest measurements of the YANS and BAHPHL instrument can be performed. Hence, these questionnaires can be used in longitudinal studies to explore young adults’ changes in attitudes toward noise, hearing loss, and hearing protection, with or without an educational intervention.

Non-Invasive Assays of Cochlear Synaptopathy - Candidates and Considerations

Studies in multiple species, including in post-mortem human tissue, have shown that normal aging and/or acoustic overexposure can lead to a significant loss of afferent synapses innervating the cochlea. Hypothetically, this cochlear synaptopathy can lead to perceptual deficits in challenging environments and can contribute to central neural effects such as tinnitus. However, because cochlear synaptopathy can occur without any measurable changes in audiometric thresholds, synaptopathy can remain hidden from standard clinical diagnostics. To understand the perceptual sequelae of synaptopathy and to evaluate the efficacy of emerging therapies, sensitive and specific non-invasive measures at the individual patient level need to be established. Pioneering experiments in specific mice strains have helped identify many candidate assays. These include auditory brainstem responses, the middle-ear muscle reflex, envelope-following responses, and extended high-frequency audiograms. Unfortunately, because these non-invasive measures can be also affected by extraneous factors other than synaptopathy, their application and interpretation in humans is not straightforward. Here, we systematically examine six extraneous factors through a series of interrelated human experiments aimed at understanding their effects. Using strategies that may help mitigate the effects of such extraneous factors, we then show that these suprathreshold physiological assays exhibit across-individual correlations with each other indicative of contributions from a common physiological source consistent with cochlear synaptopathy. Finally, we discuss the application of these assays to two key outstanding questions, and discuss some barriers that still remain. This article is part of a Special Issue entitled: Hearing Loss, Tinnitus, Hyperacusis, Central Gain.

Prevalence of Hearing Loss in US Children and Adolescents: Findings From NHANES 1988-2010

Importance

There have been concerns about increasing levels of hearing impairment in children and adolescents, especially in relation to noise exposure, because even mild levels of hearing loss can affect educational outcomes.

Objective

To further characterize changes in prevalence of hearing loss and noise exposures in the US pediatric population over time.

Design, Setting, and Participants

This is a retrospective analysis of demographic and audiometric data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994), NHANES 2005-2006, NHANES 2007-2008, and NHANES 2009-2010. The NHANES are nationally representative survey data sets collected and managed by the US National Center for Health Statistics, and this study includes a total of 7036 survey participants ages 12 to 19 years with available audiometric measurements.

Exposures

Hearing-related behaviors and risk factors such as history of ear infections, noise exposures, firearm use, and hearing protection use.

Main Outcomes and Measures

Level of hearing loss measured by pure-tone audiometry, as well as high-frequency and low-frequency hearing loss and noise-induced threshold shifts.

Results

Overall, data from 7036 survey participants ages 12 to 19 years with available audiometric measurements were analyzed. The prevalence of hearing loss increased from NHANES III to NHANES 2007-2008 (17.0% to 22.5% for >15 dB hearing loss; absolute difference, 5.5%; 95% CI, 6.1%-10.3%) but decreased in the NHANES 2009-2010 to 15.2% (absolute difference, 7.2%; 95% CI, 2.0%-12.4%) with no significant overall secular trend identified. There was an overall rise in exposure to loud noise or music through headphones 24 hours prior to audiometric testing from NHANES III to NHANES 2009-2010. However, noise exposure, either prolonged or recent, was not consistently associated with an increased risk of hearing loss across all surveys. The most recent survey cycle showed that nonwhite race/ethnicity and low socioeconomic status are independent risk factors for hearing loss.

Conclusions and Relevance

This analysis did not identify significant changes in prevalence of hearing loss in US youth ages 12 to 19 years over this time period despite increases in reported noise exposures. No consistent associations were shown between noise exposure and hearing loss, though there was an association between racial/ethnic minority status and low socioeconomic status and increased risk of hearing loss. Ongoing monitoring of hearing loss in this population is necessary to elucidate long-term trends and identify targets for intervention.

Application of the online hearing screening test "Earcheck": Speech intelligibility in noise in teenagers and young adults

Objective:

The objective was to describe the speech intelligibility in noise test results among Dutch teenagers and young adults aged 12–24 years, using a national online speech reception threshold (SRT) test, the Earcheck. A secondary objective was to assess the effect of age and gender on speech intelligibility in noise.

Design:

Cross-sectional SRT data were collected over a 5-year period (2010–2014), from participants of Earcheck. Regression analyses were performed, with SRT as the dependent variable, and age and gender as explaining variables. To cross-validate the model, data from 12- to 24-year olds from the same test distributed by a hearing aid dispenser (Hoorscan) were used.

Results:

In total, 96,803 valid test results were analyzed. The mean SRT score was −18.3 dB signal-to-noise ratio (SNR) (standard deviation (SD) = 3.7). Twenty-five percent of the scores was rated as insufficient or poor. SRT performance significantly improved with increasing age for teenagers aged 12–18 years by 0.49 dB SNR per age-year. A smaller age-effect (0.09 dB SNR per age-year) was found for young adults aged 19–24 years. Small differences between male and female users were found.

Conclusion:

Earcheck generated large quantities of national SRT data. The data implied that a substantial number of users of Earcheck may have some difficulty in understanding speech in noise. Furthermore, the results of this study showed an effect of gender and age on SRT performance, suggesting an ongoing maturation of speech-in-noise performance into late adolescence. This suggests the use of age-dependent reference values, but for this purpose, more research is required.

Epidemiology and Risk Factors for Leisure Noise-Induced Hearing Damage in Flemish Young Adults

CONTEXT

Young people regularly expose themselves to leisure noise and are at risk for acquiring hearing damage.

AIMS

The objective of this study was to compare young adults' hearing status in relation to sociodemographic variables, leisure noise exposure and attitudes and beliefs towards noise.

SETTINGS AND DESIGN

A self-administered questionnaire regarding hearing, the amount of leisure noise exposure and attitudes towards noise and hearing protection as well as an audiological test battery were completed. Five hundred and seventeen subjects between 18 and 30 years were included.

SUBJECT AND METHODS

Hearing was evaluated using conventional audiometry, transient evoked and distortion product otoacoustic emissions. On the basis of their hearing status, participants were categorised into normal hearing, sub-clinical or clinical hearing loss.

STATISTICAL ANALYSIS USED

Independent samples t-tests, chi-square tests and multiple regression models were used to evaluate the relation between groups based on hearing status, sociodemographics, leisure noise and attitudes towards noise.

RESULTS

Age was significantly related to hearing status. Although, the subjects in this study frequently participated in leisure activities, no significant associations between leisure noise exposure and hearing status could be detected. No relation with subjects' attitudes or the use of hearing protection devices was found.

CONCLUSIONS

This study could not demonstrate clinically significant leisure noise-induced hearing damage, which may lead to more non-protective behaviour. However, the effects of leisure noise may become noticeable over a long-term use since age was found to be related with sub-clinical hearing loss. Longitudinal studies are needed to evaluate the long-term effects of noise exposure.

Prevalence of Hazardous Occupational Noise Exposure, Hearing Loss, and Hearing Protection Usage Among a Representative Sample of Working Canadians

OBJECTIVE

The aim of this study was to estimate the prevalence of hearing loss (HL), self-reported occupational noise exposure, and hearing protection usage among Canadians.

METHODS

In-person household interviews were conducted with 3666 participants, aged 16 to 79 years (1811 males) with 94% completing audiometry and distortion-product otoacoustic emission (DPOAE) evaluations. Occupational noise exposure was defined as hazardous when communicating with coworkers at an arm's length distance required speaking in a raised voice.

RESULTS

An estimated 42% of respondents reported hazardous occupational noise exposure; 10 years or more was associated with HL regardless of age, sex or education. Absent DPOAEs, tinnitus, and the Wilson audiometric notch were significantly more prevalent in hazardous workplace noise-exposed workers than in nonexposed. When mandatory, 80% reported wearing hearing protection.

CONCLUSIONS

These findings are consistent with other industrialized countries, underscoring the need for ongoing awareness of noise-induced occupational HL.

Prevalência de perda auditiva em adolescentes e adultos jovens decorrentes de exposição a ruído social: meta-análise

RESUMO: A exposição a ruídos no lazer de adolescentes e jovens adultos tem chamado atenção, dada a repercussão da perda auditiva nessa população. Esse estudo propôs estimar a prevalência de perda auditiva dessa população decorrentes de exposição a ruídos sociais. Foram identificados 17 artigos para análise que atenderam aos critérios de seleção, sobre os quais se observaram informações de: delineamento, faixa etária, localização, modo de avaliação e a prevalência de perda auditiva. Nos estudos autorreferidos, a prevalência foi inferior a 2%, enquanto aqueles que realizam audiometria foi de 11,5 e de 15,8%. Concluiu-se uma heterogeneidade entre a prevalência de perda auditiva autorreferida e a mensurada por exames audiométricos na população pesquisada.

Synaptopathy in the noise-exposed and aging cochlea: Primary neural degeneration in acquired sensorineural hearing loss

The classic view of sensorineural hearing loss (SNHL) is that the "primary" targets are hair cells, and that cochlear-nerve loss is "secondary" to hair cell degeneration. Our recent work in mouse and guinea pig has challenged that view. In noise-induced hearing loss, exposures causing only reversible threshold shifts (and no hair cell loss) nevertheless cause permanent loss of >50% of cochlear-nerve/hair-cell synapses. Similarly, in age-related hearing loss, degeneration of cochlear synapses precedes both hair cell loss and threshold elevation. This primary neural degeneration has remained hidden for three reasons: 1) the spiral ganglion cells, the cochlear neural elements commonly assessed in studies of SNHL, survive for years despite loss of synaptic connection with hair cells, 2) the synaptic terminals of cochlear nerve fibers are unmyelinated and difficult to see in the light microscope, and 3) the degeneration is selective for cochlear-nerve fibers with high thresholds. Although not required for threshold detection in quiet (e.g. threshold audiometry or auditory brainstem response threshold), these high-threshold fibers are critical for hearing in noisy environments. Our research suggests that 1) primary neural degeneration is an important contributor to the perceptual handicap in SNHL, and 2) in cases where the hair cells survive, neurotrophin therapies can elicit neurite outgrowth from spiral ganglion neurons and re-establishment of their peripheral synapses. This article is part of a Special Issue entitled .

Hearing in young adults. Part II: The effects of recreational noise exposure

Great concern arises from recreational noise exposure, which might lead to noise-induced hearing loss in young adults. The objective of the current study was to evaluate the effects of recreational noise exposure on hearing function in young adults. A questionnaire concerning recreational noise exposures and an audiological test battery were completed by 163 subjects (aged 18-30 years). Based on the duration of exposure and self-estimated loudness of various leisure-time activities, the weekly and lifetime equivalent noise exposure were calculated. Subjects were categorized in groups with low, intermediate, and high recreational noise exposure based on these values. Hearing was evaluated using audiometry, transient-evoked otoacoustic emissions (TEOAEs), and distortion-product otoacoustic emissions (DPOAEs). Mean differences in hearing between groups with low, intermediate, and high recreational noise exposure were evaluated using one-way analysis of variance (ANOVA). There were no significant differences in hearing thresholds, TEOAE amplitudes, and DPOAE amplitudes between groups with low, intermediate, or high recreational noise exposure. Nevertheless, one-third of our subjects exceeded the weekly equivalent noise exposure for all activities of 75 dBA. Further, the highest equivalent sound pressure levels (SPLs) were calculated for the activities visiting nightclubs or pubs, attending concerts or festivals, and playing in a band or orchestra. Moreover, temporary tinnitus after recreational noise exposure was found in 86% of our subjects. There were no significant differences in hearing between groups with low, intermediate, and high recreational noise exposure. Nevertheless, a long-term assessment of young adults’ hearing in relation to recreational noise exposure is needed.

Hearing in young adults. Part I: The effects of attitudes and beliefs toward noise, hearing loss, and hearing protector devices

There is great concern regarding the development of noise-induced hearing loss (NIHL) in youth caused by high sound levels during various leisure activities. Health-orientated behavior of young adults might be linked to the beliefs and attitudes toward noise, hearing loss, and hearing protector devices (HPDs). The objective of the current study was to evaluate the effects of attitudes and beliefs toward noise, hearing loss, and HPDs on young adults’ hearing status. A questionnaire and an audiological test battery were completed by 163 subjects (aged 18-30 years). The questionnaire contained the Youth Attitude to Noise Scale (YANS) and Beliefs about Hearing Protection and Hearing Loss (BAHPHL). A more positive attitude or belief represented an attitude where noise or hearing loss is seen as unproblematic and attitudes and beliefs regarding HPDs is worse. Hearing was evaluated using (high frequency) pure tone audiometry (PTA), transient evoked and distortion product otoacoustic emissions. First, mean differences in hearing between the groups with different attitudes and beliefs were evaluated using one-way analysis of variance (ANOVA). Second, a χ² test was used to examine the usage of HPDs by the different groups with different attitudes and beliefs. Young adults with a positive attitude had significantly more deteriorated hearing and used HPDs less than the other subjects. Hearing conservation programs (HCPs) for young adults should provide information and knowledge regarding noise, hearing loss, and HPDs. Barriers wearing HPDs should especially be discussed. Further, those campaigns should focus on self-experienced hearing related symptoms that might serve as triggers for attitudinal and behavioral changes.

Prevalence of workers with shifts in hearing by industry: a comparison of OSHA and NIOSH Hearing Shift Criteria

OBJECTIVE

The purpose of this study was to compare the prevalence of workers with National Institute for Occupational Safety and Health significant threshold shifts (NSTS), Occupational Safety and Health Administration standard threshold shifts (OSTS), and with OSTS with age correction (OSTS-A), by industry using North American Industry Classification System codes.

METHODS

From 2001 to 2010, worker audiograms were examined. Prevalence and adjusted prevalence ratios for NSTS were estimated by industry. NSTS, OSTS, and OSTS-A prevalences were compared by industry.

RESULTS

Twenty percent of workers had an NSTS, 14% had an OSTS, and 6% had an OSTS-A. For most industries, the OSTS and OSTS-A criteria identified 28% to 36% and 66% to 74% fewer workers than the NSTS criteria, respectively.

CONCLUSIONS

Use of NSTS criteria allowing for earlier detection of shifts in hearing is recommended for improved prevention of occupational hearing loss.

Longitudinal changes in hearing threshold levels of noise-exposed construction workers

PURPOSE

Longitudinal analysis of audiometric data of a large population of noise-exposed workers provides insight into the development of noise-induced hearing loss (NIHL) as a function of noise exposure and age, particularly during the first decade of noise exposure.

METHODS

Data of pure-tone audiometry of 17,930 construction workers who underwent periodic occupational hearing screening at least twice during a 4-year period were available for analysis. These concerned all follow-up measurements of the baseline cohort described by Leensen et al. (Int Arch Occup Environ Health 84:577-590, 2011). Linear mixed models explored the relationship between the annual rate of change in hearing and noise exposure level, exposure duration, and age. Data of 3,111 workers who were tested on three occasions were used to investigate the pattern of hearing loss development.

RESULTS

The mean annual deterioration in hearing in this study population was 0.54 dB/yr, and this became larger with increasing noise exposure level and increasing age. Remarkably, during the first decade of noise exposure, an improvement in hearing threshold levels (HTLs) was observed. The change in hearing over three measurements showed a concave development of hearing loss as a function of time, which corresponds to NIHL development.

CONCLUSIONS

Overall, hearing deteriorated over the measurement period. Because HTLs at follow-up were better than those obtained at baseline, no statement can be made about the NIHL development during the first decade of noise exposure. This improvement in HTLs rather resembles the result of measurement variation in occupational screening audiometry than an actual improvement in hearing ability.

The prevention of noise induced hearing loss in children

Increasingly, our acoustic environment is filled with amplified sound sources (e.g., MP3 players, video game stations, and sports/entertainment venues). There is serious concern and also some controversy about the risks of acoustic trauma in children. This overview provides some basic information on the physiological mechanisms that lead to noise induced hearing loss, a survey of various studies that, on balance, indicates that there is cause for concern, and finally a discussion on measures that can help to prevent noise induced hearing loss in children. This paper is designed for public health and other healthcare professions (ENT, audiologists, family doctors, and pediatricians) who should understand the risks of noise induced hearing loss and its prevention.

Impact of sensory acuity on auditory working memory span in young and older adults

The impact of sensory acuity, processing speed, and working memory capacity on auditory working memory span (L-span) performance at 5 presentation levels was examined in 80 young adults (18-30 years of age) and 26 older adults (60-82 years of age). Lowering the presentation level of the L-span task had a greater detrimental effect on the older adults than on the younger ones. Furthermore, the relationship between sensory acuity and L-span performance varied as a function of age and presentation level. These results suggest that declining acuity plays an important explanatory role in age-related declines in cognitive abilities.

A retrospective analysis of noise-induced hearing loss in the Dutch construction industry

Purpose

Noise exposure is an important and highly prevalent occupational hazard in the construction industry. This study examines hearing threshold levels of a large population of Dutch construction workers and compares their hearing thresholds to those predicted by ISO-1999.

Methods

In this retrospective study, medical records of periodic occupational health examinations of 29,644 construction workers are analysed. Pure-tone audiometric thresholds of noise-exposed workers are compared to a non-exposed control group and to ISO-1999 predictions. Regression analyses are conducted to explore the relationship between hearing loss and noise intensity, noise exposure time and the use of hearing protection.

Results

Noise-exposed workers had greater hearing losses compared to their non-noise-exposed colleagues and to the reference population reported in ISO-1999. Noise exposure explained only a small proportion of hearing loss. When the daily noise exposure level rose from 80 dB(A) towards 96 dB(A), only a minor increase in hearing loss is shown. The relation of exposure time and hearing loss found was similar to ISO-1999 predictions when looking at durations of 10 years or more. For the first decade, the population medians show poorer hearing than predicted by ISO-1999.

Discussion

Duration of noise exposure was a better predictor than noise exposure levels, probably because of the limitations in noise exposure estimations. In this population, noise-induced hearing loss was already present at the beginning of employment and increased at the same rate as is predicted for longer exposure durations.

Prevalence of noise-induced hearing-threshold shifts and hearing loss among US youths

OBJECTIVE

We investigated trends in noise-induced threshold shifts (NITSs), high-frequency hearing loss (HFHL), and low-frequency hearing loss (LFHL).

METHODS

A total of 4310 adolescents 12 to 19 years of age completed audiometric testing during National Health and Nutrition Examination Surveys in 1988-1994 and 2005-2006. NITS criteria were audiometric patterns of decreased 3- to 6-kHz thresholds but preserved 0.5- to 1-kHz and 8-kHz thresholds; HFHL and LFHL criteria were high and low pure-tone averages, respectively, of >15 dB HL.

RESULTS

There were no significant increases in NITSs (odds ratio [OR]: 0.81 [95% confidence interval [CI]: 0.53-1.22]; P = .29), HFHL (OR: 1.21 [95% CI: 0.87-1.69]; P = .25), or LFHL (OR: 1.37 [95% CI: 0.77-2.45]; P = .28) between survey periods. However, a significant increase in the prevalence of NITSs occurred among female youths (11.6% [95% CI: 9.0%-14.1%] vs 16.7% [95% CI: 13.2%-20.3%]; P < .0001). The overall prevalence of exposure to loud noise or listening to music through headphones in the previous 24 hours increased from 19.8% (95% CI: 17.6%-22.1%) to 34.8% (95% CI: 31.0%-38.5%; P < .0001). In 2005-2006, female youths had a similar prevalence of exposure to recreational noise (23.6% [95% CI: 19.6%-27.6%] vs 27.7% [95% CI: 23.6%-31.8%]; P < .0001) and a lower prevalence of hearing-protection use (3.4% [95% CI: 1.6%-5.3%] vs 10.3% [95% CI: 7.3%-13.2%]; P < .0001) compared with male youths.

CONCLUSIONS

Increased exposure to recreational noise and minimal use of hearing protection might have lead to an increase in NITS prevalence among female youths.

Work and its role in shaping the social gradient in health

Adults with better jobs enjoy better health: job title was, in fact, the social gradient metric first used to study the relationship between social class and chronic disease etiology, a core finding now replicated in most developed countries. What has been less well proved is whether this correlation is causal, and if so, through what mechanisms. During the past decade, much research has been directed at these issues. Best evidence in 2009 suggests that occupation does affect health. Most recent research on the relationship has been directed at disentangling the pathways through which lower-status work leads to adverse health outcomes. This review focuses on six areas of recent progress: (1) the role of status in a hierarchical occupational system; (2) the roles of psychosocial job stressors; (3) effects of workplace physical and chemical hazard exposures; (4) evidence that work organization matters as a contextual factor; (5) implications for the gradient of new forms of nonstandard or "precarious" employment such as contract and shift work; and (6) emerging evidence that women may be impacted differently by adverse working conditions, and possibly more strongly, than men.

Effects of externally rated job demand and control on depression diagnosis claims in an industrial cohort

This study examined whether externally rated job demand and control were associated with depression diagnosis claims in a heavy industrial cohort. The retrospective cohort sample consisted of 7,566 hourly workers aged 18-64 years who were actively employed at 11 US plants between January 1, 1996, and December 31, 2003, and free of depression diagnosis claims during an initial 2-year run-in period. Logistic regression analysis was used to model the effect of tertiles of demand and control exposure on depression diagnosis claims. Demand had a significant positive association with depression diagnosis claims in bivariate models and models adjusted for demographic (age, gender, race, education, job grade, tenure) and lifestyle (smoking status, body mass index, cholesterol level) variables (high demand odds ratio = 1.39, 95% confidence interval: 1.04, 1.86). Control was associated with greater risk of depression diagnosis at moderate levels in unadjusted models only (odds ratio = 1.47, 95% confidence interval: 1.12, 1.93), while low control, contrary to expectation, was not associated with depression. The effects of the externally rated demand exposure were lost with adjustment for location. This may reflect differences in measurement or classification of exposure, differences in depression diagnosis by location, or other location-specific factors.

Acquired hearing loss in adolescents

Studies on prevalence of acquired hearing loss across the life span have shown a trend of increase in hearing loss with age. A parallel decline in age of recreational use of loud music and cigarette smoking suggests that these early listening and recreational habits may be major contributing factors to the chronic hearing disability seen in later years. In recognition of these new recreational patterns of adolescents and young adults, Healthy People 2010 has issued a list of objectives for prevention of noise-induced hearing loss and smoking in adolescents and young adults through early education and intervention. In this article, the authors describe the effects of noise- and music-induced and smoking-induced hearing loss and provide guidelines for early identification and hearing conservation. Such an early approach to identification and conservation should ultimately help reduce hearing loss prevalence rates in adults.

Prevalence of hearing loss among 18-year-old Swedish men during the period 1971-1995

AIMS

To study the hearing of 18-year-old men by using screening audiograms obtained at military conscription.

METHODS

The study group comprised 301,873 Swedish men belonging to six age cohorts born from 1953 to 1977 who had been screened at age 18 years from 1971 to 1995. The prevalence of mild to moderate hearing loss was investigated.

RESULTS

Of the entire study group, 13.1% had elevation of one or more pure tone thresholds. In most cases, 11.9%, the elevation was situated in the high-frequency region. High-frequency hearing loss was more common in the left ear (7.5%) than in the right ear (6.2%). The prevalence of hearing loss decreased during the period 1971 to 1981 from 15.7% to 8.3%. During the last part of the study period, 1986 to 1995, the prevalence increased from 9.8% to 16.3%. The increase included mild to moderate degrees of hearing loss with thresholds below 35 dB HL. The prevalence of threshold elevations was highest in sparsely populated areas of Sweden and lowest in large, metropolitan areas of Sweden from 1971 to 1986. During the last part of the study period the geographical differences decreased or disappeared.

CONCLUSIONS

The total prevalence of hearing loss was in accordance with other reports. The frequency 6 kHz was most affected by threshold elevations. The prevalence of hearing loss decreased in the first part of the study period, and increased at the end of the study period. Hearing loss was most commonly seen in rural areas.

Perceived Hearing Status and Attitudes Toward Noise in Young Adults

Purpose

To estimate the prevalence of perceived hearing loss, tinnitus, and temporary threshold shift (TTS) in community college students and to see whether those students' attitudes toward noise affected their perception of their own possible hearing loss, tinnitus, and TTS.

Method

Young adults ( N = 245; age 18–27) completed 3 questionnaires: the Hearing Symptom Description, Youth Attitude to Noise Scale, and Adolescents' Habits and Hearing Protection Use.

Results

Perceived TTS and pain associated with loud noise were the most common hearing related factors, followed by perceived tinnitus and hearing loss. The students' attitudes toward noise in their daily environment showed the most negative response, whereas attitudes toward noise and concentration indicated a more positive, or less harmful, response. Chi-square analysis indicated a significant correlation between perceived hearing loss and respondents' overall attitudes toward noise exposure. Hearing protection use was limited for all participants, with the majority reporting never having used hearing protection.

Conclusion

Approximately 6% of respondents reported perceived hearing loss, and 13.5% reported prolonged tinnitus. In general, participants had neutral attitudes toward noise. Over 20% of participants reported ear pain, tinnitus, and/or TTS after noise exposure at least sometimes. Coincidentally, few participants reported consistent use of hearing protection.