High-Frequency Audiometry for Early Detection of Hearing Loss: A Narrative Review

Early identification of potential occupational noise-induced hearing loss: a systematic review

OBJECTIVE

This systematic review addressed two questions: 1) For which audiometric test frequencies or pure tone averages are hearing threshold levels (HTLs) most susceptible to early occupational noise induced hearing loss (NIHL) before significant damage? 2) Which early flag metric best detects early hearing shifts due to noise for occupational NIHL surveillance?

DESIGN

Systematic searches were conducted in Ovid MEDLINE(R) and Embase from July 2021 to May 2024. Eligibility was screened by two independent reviewers using Covidence. HTL results were analysed for susceptibility to noise-induced changes, and sensitivity and specificity of early flag metrics were assessed.

STUDY SAMPLE

Of 175 studies retrieved, 18 met the inclusion criteria.

RESULTS

Ten studies emphasised the importance of testing at frequencies above 8 kHz, with HTLs at 12, 14, and 16 kHz frequently identified as the most noise susceptible. Conventional frequencies of 3-6 kHz were also noted as susceptible. NIOSH and OSHA metrics had low sensitivity and specificity, but modifications improved their performance to 100% sensitivity and 98% specificity.

CONCLUSION

The review highlights the need to refine current metrics and explore extended high frequencies for NIHL monitoring. Research is required to determine frequencies for warning metrics and sensitive metrics for early occupational NIHL detection.

Combined effects of benzene, toluene, xylene, ethylbenzene, and styrene exposure on hearing loss mediated by oxidative stress at realistic low levels

The link between benzene, toluene, ethylbenzene, xylene, and styrene (BTEXS) exposure and hearing loss (HL) is not well-established. This study investigated 1694 petrochemical workers in southern China to examine the effects of BTEXS urinary metabolites on auditory function, considering oxidative stress (OS) as a potential cause. Using generalized linear models, elastic net regression, and quantile g-computation, we evaluated the single and combined effects of BTEXS, OS indicators, and HL. Subgroup analysis explored interactions between BTEXS and cumulative noise exposure (CNE), while mediation analysis assessed OS's role in BTEXS-related HL. Positive associations were found between hippuric acid (HA) and HL (OR = 1.20, P < 0.05) and high-frequency hearing loss (HFHL) (OR = 1.22, P < 0.05). The ENET model linked 3&4-methylhippuric acid (3&4-MHA) with increased HFHL risk. The qgcomp model showed a 23% increased HL risk and a 20% increased HFHL risk per quartile increase in BTEXS exposure. Toluene metabolites (SBMA and HA) were significant contributors to HL, HFHL, and speech-frequency hearing loss (SFHL). Higher BTEXS SBMA, MA and HA levels exacerbated HL risk in workers exposed to CNE. Interaction analysis revealed synergistic effects between tt-MA and other metabolites on HFHL risk. Total SOD (TSOD) significantly mediated the BTEXS-HL relationship. These findings highlight a dose-effect association between BTEXS exposure and HL due to oxidative damage, with toluene metabolites being critical pollutants. BTEXS exposure also synergistically increased HL risk with noise.

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.

A Comparative Study of Hearing Handicap Inventory and Pure-Tone Audiometry Scores in Unilateral Hearing Impaired Patients

Objective: To investigate the consistency between the hearing handicap inventory (HHI) and pure-tone audiometry (PTA) scores in assessing hearing status to provide valuable insights for clinical application. Methods: Retrospective analysis of clinical data and the HHI reporting status of 6540 patients admitted between April 2020 and July 2022 for self-reported unilateral hearing loss who met the study inclusion and exclusion criteria. The kappa coefficient was used to evaluate the consistency of HHI and PTA in assessing the hearing status of the participants. Results: The PTA results showed that among the 6540 participants, 3895 exhibited normal hearing, 1434 showed mild hearing loss, 809 presented with moderate hearing loss, and 402 showed severe hearing loss. The mean hearing thresholds from 0.5 to 4 kHz in healthy ears ranged from 3.65 to 18.45 dB HL, with a mean of 10.83 ± 5.29 dB HL; in ears affected by hearing loss, this ranged from 35 to 125 dB HL, with a mean of 69.63 ± 28.45 dB HL. The HHI scores showed that 4820 people had normal hearing, 1245 had mild-to-moderate hearing loss, and 475 had severe hearing loss. The kappa coefficients of normal, mild-to-moderate, and severe hearing loss were 0.312, 0.223, and 0.716, respectively (P = .001). The consistency between the 2 groups was particularly significant in the assessment of severe hearing loss. Using the PTA results as a benchmark, the sensitivity, specificity, positive predictive value, and negative predictive value of the HHI were found to be 73.08%, 87.83%, 95.60%, and 70.98%, respectively. Conclusion: The HHI and PTA results were consistent in the assessment of hearing status, particularly in the assessment of severe hearing loss, and the level of consistency between the 2 methods was high. The combined use of these tools can facilitate a comprehensive assessment of the auditory status of patients with hearing loss.

Relationship between hypertension/blood pressure and hearing sensitivity among drivers: A correlation analysis

BACKGROUND

One of the most common chronic diseases is hypertension. The majority of research has linked hearing loss to hypertension. However, the relationship between hypertension and hearing is still unknown. The primary goal of the study is to investigate the effect of hypertension on hearing and to find out the association between blood pressure levels and auditory health in auto-rickshaw drivers.

MATERIALS AND METHODS

The study utilized 121 healthy professional auto-drivers between the age range of 25 and 55 years. Pure-tone audiometry (PTA) and extended high-frequency audiometry (EHFA) were used to determine the participants' hearing thresholds from 0.25 to 16 kHz. The cochlear hair cell functioning was evaluated using distortion-product otoacoustic emission (DPOAE) testing. Blood pressure (mmHg) measurements were categorized under hypertension stage (normal (120; <80); elevated (120-129; <80); hypertension - stage 1 (130-139; 80-89); hypertension - stage 2 (≥140; ≥90)).

RESULTS

The mean age of the study participants was 42.17 ± 9.03 years. The mean systolic and diastolic BP of all the study participants were 138.24 ± 19.73 (105-216) mmHg and 87.69 ± 12.14 (60-134) mmHg, respectively. BP levels were normal for 17.4% (N = 21) of the study participants, 21.5% (N = 26) had elevated blood pressure, 21.5% (N = 26) of the population falls under stage 1 hypertension, and 39.7% (N = 48) had stage 2 hypertension. Our study discovered a significant difference between main group effects and no significant difference between group interaction effects. Hearing thresholds were significantly higher in hypertensive participants compared to non-hypertensive participants. However, there was no statistically significant relationship between the two variables hypertension and hearing loss.

CONCLUSION

Implementing health promotion initiatives and raising awareness about hearing health could improve the quality of life for a high-risk occupational group of drivers.

Peripheral vestibular loss in noise-exposed firefighters

Introduction

Occupational workers are increasingly aware of the risk of noise overexposure to the auditory system but lack awareness about potential risks to the vestibular system. The purpose of this study was to investigate changes in vestibular end organ function in a known at-risk noise-exposed population, firefighters compared to age- and sex-matched controls using electrophysiologic measures of cervical vestibular evoked myogenic potentials (cVEMP).

Methods

A cross-sectional observational study compared cVEMP response characteristics in 38 noise-exposed firefighters. Firefighters were grouped by years of exposure in the fire service. The cVEMP responses were compared within firefighter groups and between firefighters and age- and sex-matched controls. Dependent variables included the response characteristics of amplitude, latency and threshold.

Results

cVEMP response amplitudes were significantly decreased in firefighters compared to their age- and sex-matched controls. Threshold of the cVEMP responses were significantly higher in firefighters compared to controls and firefighters had a higher incidence of absent cVEMP responses compared to controls. Response amplitudes decreased with increasing years in the fire-service at an increased rate compared to their age- and sex-matched controls. Latency of the cVEMP response was not significantly different in firefighters compared to controls. These findings are consistent with both animal and human studies suggesting noise-induced changes in the sacculocollic pathway.

Discussion

In the absence of any reported vestibular symptoms or auditory indicators of noise-induced hearing loss, these early effects on the vestibular system point to a potential hidden vestibular loss.

The effect of recreational noise exposure on amplitude-modulation detection, hearing sensitivity at frequencies above 8 kHz, and perception of speech in noise

Psychoacoustic and speech perception measures were compared for a group who were exposed to noise regularly through listening to music via personal music players (PMP) and a control group without such exposure. Lifetime noise exposure, quantified using the NESI questionnaire, averaged ten times higher for the exposed group than for the control group. Audiometric thresholds were similar for the two groups over the conventional frequency range up to 8 kHz, but for higher frequencies, the exposed group had higher thresholds than the control group. Amplitude modulation detection (AMD) thresholds were measured using a 4000-Hz sinusoidal carrier presented in threshold-equalizing noise at 30, 60, and 90 dB sound pressure level (SPL) for modulation frequencies of 8, 16, 32, and 64 Hz. At 90 dB SPL but not at the lower levels, AMD thresholds were significantly higher (worse) for the exposed than for the control group, especially for low modulation frequencies. The exposed group required significantly higher signal-to-noise ratios than the control group to understand sentences in noise. Otoacoustic emissions did not differ for the two groups. It is concluded that listening to music via PMP can have subtle deleterious effects on speech perception, AM detection, and hearing sensitivity over the extended high-frequency range.

Dietary magnesium and calcium intake is associated with lower risk of hearing loss in older adults: A cross-sectional study of NHANES

Aim

Dietary intake as a modifiable factor has been reported to be associated with hearing loss (HL). The relationship between magnesium (Mg) and calcium (Ca) as common dietary nutrients and HL in the elderly has rarely been reported. This study aimed to assess the association between Mg and Ca intake and HL in older adults.

Method

This cross-sectional study included participants aged ≥70 years from the National Health and Nutrition Examination Survey (NHANES) 2005–2006, 2009–2010, and 2017–2018. Outcomes were low-frequency [pure-tone averages (PTAs) at 500, 1000, and 2000 Hz &gt;25 dB] and speech-frequency (PTAs at 500, 1000, 2000, and 4,000 Hz &gt;25 dB) HL. Multivariate logistic analysis was utilized to explore the association between dietary Mg and Ca intake and their combined intake (Ca/Mg, Ca*Mg) and HL, and was described as odds ratio (OR) and 95% confidence interval (CI).

Results

A total of 1,858 participants were included, of which 1,052 (55.95%) had low-frequency HL and 1,349 (72.62%) had speech-frequency HL. Dietary Ca intakes [OR = 0.86, 95%CI: (0.74–0.99)] and Mg intakes [OR = 0.81, 95%CI: (0.68–0.95)] and Ca * Mg [OR = 0.12, 95%CI: (0.02–0.87)] were associated with lower odds of low-frequency HL after adjusting for confounders. Similar, dietary Ca intakes [OR = 0.85, 95%CI: (0.77–0.95)] and Mg intakes [OR = 0.78, 95%CI: (0.68–0.90)] and Ca * Mg [OR = 0.23, 95%CI: (0.05–0.78)] were related to lower odds of speech-frequency HL. For different levels of Mg and Ca intake, the combined intake of Ca (≥1,044 mg) and Mg (≥330 mg) was related to lower odds of low-frequency HL [OR = 0.02, 95%CI: (0.00–0.27)] and speech-frequency HL [OR = 0.44, 95%CI: (0.21–0.89)].

Conclusion

Dietary intakes of Mg and Ca were associated with lower odds of HL and are a promising intervention to be further explored in older adults with HL.

Extended high-frequency audiometry: hearing thresholds in adults

PURPOSE

This study aimed to determine hearing thresholds in an otologically normal population without occupational noise exposure aged 18 to 64 years using extended high-frequency audiometry (EHFA).

METHODS

Individuals from the general population who have never had hearing problems and whose job was not associated with noise exposure were included in the study and classified by age into 5 categories: 18-24 and, further, by 10 years of age. Each of these groups was further divided according to gender. All subjects underwent tympanometry, conventional pure-tone audiometry within the 0.125-8 kHz range, and extended high-frequency audiometry within the 9-16 kHz range, performed according to the standards. The significance level for statistical testing was set at 5%.

RESULTS

Here, we established hearing thresholds in an otologically healthy population within the extended high-frequency (EHF) range (9-16 kHz). We found the EHFA to be a highly sensitive method for early detection of hearing loss, with hearing thresholds decreasing as soon as 35 years of age. In males, the hearing thresholds grew with age more rapidly than in women. The ability to respond at EHF gradually decreased with age and increasing frequency.

CONCLUSION

Our results can help improve the knowledge of EHF hearing thresholds for individual sexes and age groups. So far, the standard 7029:2017 is not binding and, moreover, it only reaches up to the frequency of 12.5 kHz. EHFA is a highly sensitive method for the evaluation of hearing loss depending on age and sex.

The effect of age and hearing sensitivity at frequencies above 8 kHz on auditory stream segregation and speech perception

The effects of age and mild hearing loss over the extended high-frequency (EHF) range from 9000 to 16 000 Hz on speech perception and auditory stream segregation were assessed using four groups: (1) young with normal hearing threshold levels (HTLs) over both the conventional and EHF range; (2) older with audiograms matched to those for group 1; (3) young with normal HTLs over the conventional frequency range and elevated HTLs over the EHF range; (4) older with audiograms matched to those for group 3. For speech in quiet, speech recognition thresholds and speech identification scores did not differ significantly across groups. For monosyllables in noise, both greater age and hearing loss over the EHF range adversely affected performance, but the effect of age was much larger than the effect of hearing status. Stream segregation was assessed using a rapid sequence of vowel stimuli differing in fundamental frequency (F0). Larger differences in F0 were required for stream segregation for the two groups with impaired hearing in the EHF range, but there was no significant effect of age. It is argued that impaired hearing in the EHF range is associated with impaired auditory function at lower frequencies, despite normal audiometric thresholds at those frequencies.

Auditory changes following firearm noise exposure, a review

Firearms produce peak sound pressure levels (peak SPL) between ∼130 and 175 dB peak SPL, creating significant risk of noise-induced hearing loss (NIHL) in those exposed to firearm noise during occupational, recreational, and/or military operations. Noise-induced tinnitus and hearing loss are common in military service members, public safety officers, and hunters/shooters. Given the significant risk of NIHL due to firearm and other noise sources, there is an interest in, and demand for, interventions to prevent and/or treat NIHL in high-risk populations. However, research and clinical trial designs assessing NIHL prevention have varied due to inconsistent data from the literature, specifically with end point definitions, study protocols, and assessment methodologies. This article presents a scoping review of the literature pertaining to auditory changes following firearm noise exposure. Meta-analysis was not possible due to heterogeneity of the study designs. Recommendations regarding audiologic test approach and monitoring of populations at risk for NIHL are presented based on critical review of the existing literature.

Early detection of noise-induced hearing loss

BACKGROUND

Noise-induced hearing loss (NIHL) is the second most common acquired hearing loss following presbycusis. Exposure to recreational noise and minimal use of hearing protection increase the prevalence of NIHL in young females. NIHL is irreversible. Identifying minor hearing pathologies before they progress to hearing problems that affect daily life is crucial.

AIM

To compare the advantages and disadvantages of extended high frequency (EHF) and otoacoustic emission and determine an indicator of hearing pathologies at the early sub-clinical stage.

METHODS

This cross-sectional study was implemented in West China Hospital of Sichuan University from May to September 2019. A total of 86 participants, aged 18-22 years, were recruited to establish normative thresholds for EHF. Another 159 adults, aged 18-25 years with normal hearing (0.25-8 kHz ≤ 25 dBHL), were allocated to low noise and noise exposure groups. Distortion otoacoustic emission (DPOAE), transient evoked otoacoustic emissions (TEOAE), and EHF were assessed in the two groups to determine the superior technique for detecting early-stage noise-induced pathologies. The chi-square test was used to assess the noise and low noise exposure groups with respect to extended high-frequency audiometry (EHFA), DPOAE, and TEOAE. P ≤ 0.05 was considered statistically significant.

RESULTS

A total of 86 participants (66 females and 20 males) aged between 18 and 22 (average: 20.58 ± 1.13) years were recruited to establish normative thresholds for EHF. The normative thresholds for 9, 10, 11.2, 12.5, 14, 16, 18, and 20 kHz were 15, 10, 20, 15, 15, 20, 28, and 0 dBHL, respectively. A total of 201 participants were recruited and examined for eligibility. Among them, 159 adults aged between 18 and 25 years were eligible in this study. No statistical difference was detected between the noise exposure and the low noise exposure groups using EHFA, DPOAE, and TEOAE (P > 0.05) except in the right ear at 4 kHz using TEOAE (abnormal rate 20.4% vs 5.2%, respectively; P = 0.05).

CONCLUSION

These results showed TEOAE as the earliest indicator of minor pathology compared to DPOAE and EHFA. However, a multicenter controlled study or prospective study is essential to verify these results.

[A cross-sectional study and risk factors analysis of tinnitus in flight support personnel of PLA air force]

Objective:The aim of this study is to understand the epidemiological characteristics of tinnitus among flight support personnel and analyze its audiological characteristics and related risk factors. Methods:The information of tinnitus was collected by a method of cross-sectional investigation using questionnaire survey and audiology test among the flight support personnel of two stations of PLA air force. Results:The incidence of tinnitus among 666 subjects included was 24.2%, the THI grade was mainly grade 1 and grade 2. There were differences in THI scores among groups with different working years, but only differences in tinnitus incidence among groups with different frequency of hearing loss. Multivariate logistic regression analysis showed that grade of high frequency hearing loss（OR=1.39）, conscious hearing loss（OR=1.79） and frequency of asking others to repeat words（OR=1.64） were independent risk factors of tinnitus. The incidence of HF-HL and EHF-HL in ears with tinnitus among 0-5 working years was higher than that without tinnitus, while the incidence of EHF-HL in ears with tinnitus was not different from that without tinnitus among 6-10 and >10 working years. There was moderate correlation between THI scores and SAS standard scores（r=0.759）, and weak correlation between THI scores and PSQI scores（r=0.445）. Conclusion:The risk of tinnitus in high-frequency hearing loss and recessive hearing loss is increased; working years can affect the severity of tinnitus, while hearing conditions at different frequencies only affect the incidence of tinnitus; with increasing age, noise exposure plays a role in the occurrence of tinnitus decreasing gradually.

Analysis of Early Biomarkers Associated With Noise-Induced Hearing Loss Among Shipyard Workers

IMPORTANCE

It is important to determine what frequencies and auditory perceptual measures are the most sensitive early indicators of noise-induced hearing impairment.

OBJECTIVES

To examine whether hearing loss among shipyard workers increases more rapidly at extended high frequencies than at clinical frequencies and whether subtle auditory processing deficits are present in those with extensive noise exposure but little or no hearing loss.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study collected audiometric data (0.25-16 kHz), survey questionnaires, and noise exposure levels from 7890 shipyard workers in a Shanghai shipyard from 2015 to 2019. Worsening hearing loss was evaluated in the group with hearing loss. Speech processing and temporal processing were evaluated in 610 participants with noise exposure and clinically normal hearing to identify early biomarkers of noise-induced hearing impairment. Data analysis was conducted from November to December 2020.

MAIN OUTCOMES AND MEASURES

Linear regression was performed to model the increase in hearing loss as function of cumulative noise exposure and compared with a group who were monitored longitudinally for 4 years. Auditory processing tests included speech-in-noise tests, competing sentence tests, dichotic listening tests, and gap detection threshold tests and were compared with a control group without history of noise exposure.

RESULTS

Of the 5539 participants (median [interquartile range (IQR)] age, 41.0 [34.0-47.0] years; 3861 [86.6%] men) included in the cross-sectional analysis, 4459 (80.5%) were hearing loss positive and 1080 (19.5%) were hearing loss negative. In younger participants (ie, ≤40 years), the maximum rate of increase in hearing loss was 0.40 (95% CI, 0.39-0.42) dB per A-weighted dB-year (dB/dBA-year) at 12.5 kHz, higher than the growth rates of 0.36 (95% CI, 0.35-0.36) dB/dBA-year at 4 kHz, 0.32 (95% CI, 0.31-0.33) dB/dBA-year at 10 kHz, 0.31 (95% CI, 0.30-0.31) dB/dBA-year at 6 kHz, 0.27 (95% CI, 0.26-0.27) dB/dBA-year at 3 kHz, and 0.27 (95% CI, 0.27-0.28) dB/dBA-year at 8 kHz. In the 4-year longitudinal analysis of hearing loss among 403 participants, the mean (SD) annual deterioration in hearing was 2.70 (2.98) dB/y at 12.5 kHz, almost twice as that observed at lower frequencies (eg, at 3kHz: 1.18 [2.15] dB/y). The auditory processing scores of participants with clinically normal hearing and a history of noise exposure were significantly lower than those of control participants (eg, median [IQR] score on speech-in-noise test, noise-exposed group 1 vs control group: 0.63 [0.55-0.66] vs 0.78 [0.76-0.80]; P < .001).

CONCLUSIONS AND RELEVANCE

These findings suggest that the increase in hearing loss among shipyard workers was more rapid at 12.5 kHz than at other frequencies; workers with clinically normal hearing but high cumulative noise exposure are likely to exhibit deficits in speech and temporal processing.