Noise-induced Hearing Threshold Shifts Research Articles

Noise-Induced Hearing Threshold Shift Correlated with Body Weight and External-Ear Amplification in Chinchilla: a Preliminary Analysis

BackgroundExternal-ear amplification (EEA) has been shown to vary from 5–19 dB-A in large datasets of pediatric, adolescent, and adult human participants. However, variable EEA is an overlooked characteristic that likely plays a role in individual noise-induced hearing loss (NIHL) susceptibility. A noise exposure varying 5–19 dB-A translates to high-EEA individuals theoretically experiencing 3–4 times greater NIHL risk than low-EEA individuals.ObjectiveThe purpose of this preliminary analysis was to test the hypothesis that higher EEA is correlated with increased noise-induced threshold shift susceptibility.DesignNine chinchillas were exposed to 4-kHz octave-band noise at 89 dB-SPL for 24 h. Auditory brainstem response thresholds were obtained pre-exposure, 24-h post-exposure, and 4-week post-exposure. Relationships between EEA and threshold shift were analyzed.ResultsOpen-ear EEA ranged 11–19 dB-SPL, and occluded-ear EEA ranged 10–21 dB-SPL. Higher occluded-ear EEA was correlated with increased NIHL susceptibility (p = 0.04), as was lower body weight (p = 0.01). Male animals exhibited more threshold shift than female animals (p = 0.02), lower body weight than female animals (p = 0.02), and higher occluded-ear EEA (male mean = 18 dB; female mean = 15 dB).ConclusionsTaken together, increased threshold shift susceptibility was observed in the smallest animals, animals with the highest occluded-ear EEA, and in male animals (which tended to have higher occluded-ear EEA). Given the established relationship between smaller body size and higher occluded-ear EEA, these preliminary results suggest that body size (and occluded-ear EEA; a function of body size) could be a potential, underlying driver of NIHL susceptibility differences, rather than true sex differences.

Monitoring of noise-induced hearing threshold shifts among adolescents: The relevance of exposure to leisure noise in the prospective Ohrkan cohort study

Introduction: Exposure to high continuous noise during leisure activities such as attending discotheques or listening to portable listening devices at high volume levels is presumed to have harmful effects on the hearing system of young adolescents. Therefore, the follow-up study Ohrkan funded by the Bavarian State Ministry for the Environment and Health was initiated to track its members over a 10 years period. Currently, the 5-year follow-up is ongoing. Objectives: Analysis of the association of hearing threshold shifts and total leisure noise exposure over five years. Methods: A total of 2,149 students of grade 9 (mostly aged 15-16 years) in the City of Regensburg were recruited from 2009-2011. In the baseline survey and in the recent survey five years later exposure to leisure noise was assessed by self-administered questionnaire and audiometric examinations were performed at the university hospital of Regensburg. The self-reported frequency of participation in noisy activities was combined with literature-based values of usual sound pressure levels of these activities to calculate the total leisure noise exposure. Two different outcomes were defined: a noise notch with a distinct audiometric pattern as well as the maximum threshold shift of both ears at 3, 4, 6 kHz. A longitudinal analysis of these data by generalized linear models (GLM) is in progress to determine the long-term effects of total leisure noise exposure. Results: Up to now, data from over 1,000 students are available. The study methods including the statistical model as well as the latest results using 5-year follow-up data will be presented. Conclusions: Results will be discussed with respect to the burden of leisure noise exposure and the association with the hearing ability of adolescents. Potential implications for the development of early prevention programs and for regulatory measures to reduce leisure noise exposure will be suggested.

The prevalence of noise-induced hearing threshold shifts in adolescents: The Ohrkan-study

Background: While noise exposure at the workplace is regulated to minimize the risk of hearing loss, leisure noise exposure is likely to pose a risk for hearing as well. However, valid recent data ...

Investigation of screening methods for identifying population susceptible to noise-induced hearing loss

To investigate the screening methods for identifying the populations susceptible and resistant to noise-induced hearing loss (NIHL) and to provide a reference for future research. Workers who were exposed to 75 ∼ 120 dB noise in enterprises were included in the study. Field investigation of occupational health was conducted; workers' basic information and data on hearing threshold levels were collected. Paired chi-square test was used to compare each two of three screening methods, which were used at home and abroad to identify noise-susceptible and noise-sensitive populations, in terms of noise exposure level, general information, and noise-induced hearing threshold shift. There were no significant differences in the noise exposure level, basic information, and left and right ears' hearing threshold levels of noise-susceptible and noise-sensitive populations between each two of the three screening methods (P > 0.05), according to the paired chi-square test. However, high-frequency hearing threshold had statistically significant difference among the three methods. As a whole, methods B and C were superior to method A. The workers in China are younger than before, with more awareness of self-protection, and individual protection is enhanced in them. Currently, method B is more suitable for screening out the population susceptible to NIHL in China.

Noise-induced hearing threshold shift among US adults and implications for noise-induced hearing loss: National Health and Nutrition Examination Surveys

The objective of this study was to estimate the prevalence and evaluate the associated risk factors of the noise-induced hearing threshold shift (NITS) in the US adult population based on the National Health and Nutrition Examination Surveys (NHANES). The study population consisted of 5,418 individuals aged 20-69 years who had complete audiologic data from the NHANES database. Stringent criteria were used to define NITS. Prevalence of unilateral, bilateral, and total NITS and their association with several socio-demographic and hearing-related factors were evaluated. The prevalence of unilateral, bilateral, and total NITS was 9.4, 3.4 and 12.8%, respectively. Prevalence of bilateral NITS was higher in subjects with older age, male gender, white (non-Hispanic) and Hispanic ethnicities, education level less than or equal to high school diploma, married/living with partner status, Mexico as country of birth, service in armed forces, smoking history, diabetes, and different kinds of noise exposure. Odds of NITS were only higher in older people, males, and smokers. This study provides comprehensive information on the prevalence of NITS in the US adult population and its associated risk factors. More targeted interventions may be done for educational, preventative, and screening purposes.

Otoacoustic detection of risk of early hearing loss in ears with normal audiograms: A 3-year follow-up study

Introduction Distortion product otoacoustic emissions (DPOAEs) are known to represent the contractile amplifier function of cochlear outer hair cells. It is known that low or absent DPOAEs are associated with hearing loss on audiograms. However, low DPOAEs can also be found associated with normal audiograms. It is unknown whether low DPOAEs in normal hearing ears are risk markers for subsequent early hearing loss when subjects are exposed to noise. Materials and methods A 3-year follow-up study was carried out on a population of pilots aged 20–40 years ( n = 521). Data collection consisted of tonal audiograms, DPOAEs measurements with a calculation of an index of abnormality (the IaDPOAE). Of the 521 pilots enrolled, 350 (67%) had follow-up data 3 years later. In pilots with normal audiograms ( n = 219, all frequencies = 10 dB HL), we observed the occurrence of hearing threshold shifts after 3 years depending on whether the IaDPOAE was initially high (group 1) or low (group 2). We used this index to test the hypothesis that reduced DPOAEs levels are potential ear vulnerability biomarkers in apparent normal hearing ears. After a 3-year follow-up, the initial IaDPOAE in normal hearing subjects was correlated with final noise-induced hearing threshold shifts at high frequencies ( p < 0.01). The occurrence of abnormal audiograms was significantly higher in group 1 compared to group 2 ( p = 0.003). In group 1, 13% of audiograms were found with at least one frequency ⩾25 dB HL compared to 3% of audiograms in group 2. In both groups, impairments occurred at high frequencies and hearing in the 4 kHz frequency range was significantly more impaired in group 1 ( p = 0.035). Group 1 was associated with a relative risk of 2.29 (95% CI 1.26–4.16, p = 0.005) of sustaining early hearing loss. There was no significant differences between groups for age and noise exposure. Discussion In adults with a normal audiogram, ear vulnerability to noise could be elicited by the use of objective DPOAE measurements. A high IaDPOAE that corresponded to reduced DPOAE levels constitutes a risk for early hearing loss. This study emphasised the interest of DPOAE measurements in public health and occupational noise prevention policies. The IaDPOAE calculation may also be interesting for clinicians because no DPOAE index of abnormality is currently available.

Advances in Hearing Conservation Practices: An Interview With Mark Stephenson

Abstract It is estimated that 30 million Americans are exposed to hazardous noise levels at work (Stephenson et al., 2003). The Occupational Safety and Health Act of 1970 created two separate agencies dedicated to promoting worker health and safety: the Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH). Research at NIOSH informs OSHA regulations. This report comprises an interview with Mark Stephenson, PhD, Scientific Research Coordinator for the NIOSH noise and hearing loss research program. He provides insights into the latest advances in hearing conservation practices, what works and why. Current hearing conservation practices developed at NIOSH and not yet mandated by OSHA use methods borrowed from evidence-based health communication theories to change the ways individuals view the problem of noise exposure, eliminate barriers that prevent effective hearing protector use, and create a culture of self-efficacy with respect to hear...

Innovations in Preventing Noise-Induced Hearing Loss and Tinnitus

No AccessPerspectives on Hearing and Hearing Disorders: Research and DiagnosticsArticle1 Apr 2004Innovations in Preventing Noise-Induced Hearing Loss and Tinnitus William Hal Martin, Susan E. Griest and Linda C. Howarth William Hal Martin Department of Otolaryngology, Oregon Hearing Research Center, Oregon Health & Science UniversityPortland, OR Google Scholar More articles by this author , Susan E. Griest Department of Otolaryngology, Oregon Hearing Research Center, Oregon Health & Science UniversityPortland, OR Google Scholar More articles by this author and Linda C. Howarth Department of Otolaryngology, Oregon Hearing Research Center, Oregon Health & Science UniversityPortland, OR Google Scholar More articles by this author https://doi.org/10.1044/hhd8.1.12 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationTrack Citations ShareFacebookTwitterLinked In References FolmerR. L. (2002). Why aren’t hearing conservation practices taught in schools?.Educational Audiology Review, 10, 12–16. Google Scholar Folmer, R. L., Griest, S. E., & Martin, W. H. (2002). Hearing conservation education programs for children: A review.Journal of School Health, 72 (2), 51–5. CrossrefMedlineGoogle Scholar Montgomery, J. K., & Fujikawa, S. (1992). Hearing thresholds of students in the second, eighth and twelfth grades.Language, Speech, and Hearing Services in Schools, 23, 61–63. ASHAWireGoogle Scholar Niskar, A. S., Kieszak, S. M., Holmes, A. E., Esteban, E., Rubin, C., & Brody, D. J. (2001). Estimated prevalence of noise-induced hearing threshold shifts among children 6 to 19 years of age: The third national health and nutrition examination survey, 1988–1994, United States.Pediatrics, 108(1), 40–43. CrossrefMedlineGoogle Scholar Strategies for Prevention of Deafness and Hearing Impairment, Number 3 (1997). Prevention of noise-induced hearing loss.Report of a World Health Organization-Prevention of Deafness and Hearing Impairment Informal Consultation (Geneva, p. 6). Retrieved April 7, 2004, from www.who.int/pbd/pdh/Docs/NOISEREP_V08.pdf Google Scholar Additional Resources FiguresReferencesRelatedDetails Volume 8Issue 1April 2004Pages: 12-15 Get Permissions Add to your Mendeley library History Published in issue: Apr 1, 2004 Metrics Topicsasha-topicsleader-topicsasha-sigsasha-article-typesCopyright & Permissions© 2004 American Speech-Language-Hearing AssociationPDF DownloadLoading ...

Estimated prevalence of noise-induced hearing threshold shifts among children 6 to 19 years of age: the Third National Health and Nutrition Examination Survey, 1988-1994, United States.

This analysis estimates the first nationally representative prevalence of noise-induced hearing threshold shifts (NITS) among US children. Historically, NITS has not been considered a common cause of childhood hearing problems. Among children, NITS can be a progressive problem with continued exposure to excessive noise, which can lead to high-frequency sound discrimination difficulties (eg, speech consonants and whistles). The Third National Health and Nutrition Examination Survey (NHANES III) was conducted from 1988 to 1994. NHANES III is a national population-based cross-sectional survey with a household interview, audiometric testing at 0.5 to 8 kHz, and compliance testing. A total of 5249 children aged 6 to 19 years completed audiometry and compliance testing for both ears in NHANES III. The criteria used to assess NITS included audiometry indicating a noise notch in at least 1 ear. Of US children 6 to 19 years old, 12.5% (approximately 5.2 million) are estimated to have NITS in 1 or both ears. In the majority of the children meeting NITS criteria, only 1 ear and only 1 frequency are affected. In this analysis, all children identified with NITS passed compliance testing, which essentially rules out middle ear disorders such as conductive hearing loss. The prevalence estimate of NITS differed by sociodemographics, including age and sex. These findings suggest that children are being exposed to excessive amounts of hazardous levels of noise, and children's hearing is vulnerable to these exposures. These data support the need for research on appropriate hearing conservation methods and for NITS screening programs among school-aged children. Public health interventions such as education, training, audiometric testing, exposure assessment, hearing protection, and noise control when feasible are all components of occupational hearing conservation that could be adapted to children's needs with children-specific research.

Activities of Na +,K +-ATPase and Ca 2+-ATPase in cochlear lateral wall after acoustic trauma

Na +,K +-ATPase and Ca 2+-ATPase are well known participants in the active transport of ions in the inner ear. These two enzymes play an important role in maintaining cochlear function. Although changes in these enzymes’ activities in the cochlea have been implicated in noise-induced hearing loss, no evidence of quantitative alteration of Na +,K +-ATPase or Ca 2+-ATPase activities has ever been shown. The present study was undertaken to determine the quantitative alterations of their activities by microcolorimetric assay in the cochlear lateral wall after acoustic trauma. Adult albino guinea pigs were exposed to white noise at 105±2 dB A for 10 min or 40 h. The age-matched control animals were not exposed to noise. Noise exposure resulted in a significant threshold shift of the auditory brainstem response ( P<0.001). Significant decreases in activities of Na +,K +-ATPase and Ca 2+-ATPase were found in the cochlear lateral wall after noise exposure ( P<0.001). Statistical analysis indicated that a good correlation held not only between the decline of these enzyme activities and noise-induced hearing loss, but also between the gradual partial recovery of these parameters during the first 10-day recovery period. The present findings suggest that metabolic damage and ionic disturbance may contribute, at least partially, to noise-induced hearing threshold shift.

Noise-exposed male sheet-metal workers using hearing protectors. A longitudinal study of hearing threshold shifts covering fifteen years.

The hearing thresholds of male sheet-metal workers have been studied in a longitudinal investigation with pure tone audiometry during three periods covering 1972-1987. Using these data, the hearing threshold shifts were calculated in various age groups. When the annual rate of mean hearing threshold shift over the frequency range 2-8 kHz was considered, it was not possible to establish a difference in the threshold shift between noise-exposed groups and an otologically normal 'highly screened' male population from ISO 7029, database A. The correction for ageing in the noise-exposed group according to the empirical formula in ISO 1999 (1990) is discussed. The results show that a hearing conservation programme including effective use of hearing protectors and reduction of noise emission levels can eliminate noise-induced hearing threshold shifts and progressive hearing loss.