The risks of amplified music for disc-jockeys working in nightclubs

Loud Music and Leisure Noise Is a Common Cause of Chronic Hearing Loss, Tinnitus and Hyperacusis

High sound levels capable of permanently damaging the ear are experienced not only in factories and war zones but in concert halls, nightclubs, sports stadiums, and many other leisure environments. This review summarizes evidence that loud music and other forms of "leisure noise" are common causes of noise-induced hearing loss, tinnitus, and hyperacusis, even if audiometric thresholds initially remain within clinically normal limits. Given the huge global burden of preventable noise-induced hearing loss, noise limits should be adopted in a much broader range of settings, and education to promote hearing conservation should be a higher public health priority.

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.

Pilot study of patron sound level exposure in loud restaurants, bars, and clubs in New York city

Visiting restaurants, bars, clubs, and lounges is a regular part of urban cultural life for residents and tourists alike; however, anecdotal reports and diner surveys suggest that sound levels are excessive and diners dislike them. High sound levels in these venues can contribute to both patron and employee overexposure, and young people may be particularly at risk. To supplement the paucity of literature and data on noise in urban venues, patron noise exposure was measured inside a sample of loud New York City restaurants, bars, clubs, and lounges. Sound level measurements were obtained in 59 venues. Field staff conducted one 20-162 minute visit per venue on a Thursday, Friday, or Saturday evening. The equivalent continuous sound pressure level on the A-scale (L_Aeq) was calculated for each visit. Median and mean L_Aeq among all venues sampled were both 92 decibels (dBA). Clubs and lounges had a higher mean L_Aeq than restaurants and bars (97 vs. 91 dBA, p < 0.05). A greater number of patrons was associated with a higher L_Aeq. Higher L_Aeq values were observed during later hours of the evening (9 PM and later). For 80% (N = 47) of the venues, the L_Aeq was above 85 dBA. In 49% (N = 29) of the venues, the visit exceeded the maximum allowable daily noise dose based on National Institute of Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL) of 85 dBA 8-hr Time-Weighted Average (TWA). Venues should assess indoor sound levels including employee exposure and aim to maintain sound levels that are within NIOSH guidelines.

Amplitude-modulation detection by recreational-noise-exposed humans with near-normal hearing thresholds and its medium-term progression

Noise exposure can affect the functioning of cochlear inner and outer hair cells (IHC/OHC), leading to multiple perceptual changes. This work explored possible changes in detection of amplitude modulation (AM) at three Sensation Levels (SL) for carrier frequencies of 3, 4 and 6 kHz. There were two groups of participants, aged 19 to 24 (Young) and 26 to 35 (Older) years. All had near-normal audiometric thresholds. Participants self-assessed exposure to high-level noise in recreational settings. Each group was sub-grouped into low-noise (LN) or high-noise (HN) exposure. AM detection thresholds were worse for the HN than for the LN sub-group at the lowest SL, for the males only of the Young group and for both genders for the Older group, despite no significant difference in absolute threshold at 3 and 4 kHz between sub-groups. AM detection at the lowest SL, at both 3 and 4 kHz, generally improved with increasing age and increasing absolute threshold, consistent with a recruitment-like process. However, poorer AM detection was correlated with increasing exposure at 3 kHz in the Older group. It is suggested that high-level noise exposure produces both IHC- and OHC-related damage, the balance between the two varying across frequency. However, the use of AM detection offers poor sensitivity as a measure of the effects.

Epidemiology of noise-induced tinnitus and the attitudes and beliefs towards noise and hearing protection in adolescents

Background and objectives

Previous research showed an increase of noise-induced symptoms in adolescents. Permanent tinnitus as a consequence of loud music exposure is usually considered as noise-induced damage. The objective was to perform an epidemiological study in order to obtain prevalence data of permanent noise-induced tinnitus as well as temporary tinnitus following noise exposure in a young population. In addition the attitudes and beliefs towards noise and hearing protection were evaluated in order to explain the use/non-use of hearing protection in a young population.

Methods

A questionnaire was completed by 3892 high school students (mean age: 16.64 years old, SD: 1.29 years). The prevalence of temporary and permanent tinnitus was assessed. In addition the ‘Youth Attitudes to Noise Scale’ and the ‘Beliefs About Hearing Protection and Hearing Loss’ were used in order to assess the attitudes and beliefs towards noise and hearing protection respectively.

Results

The prevalence of temporary noise-induced tinnitus and permanent tinnitus in high school students was respectively 74.9% and 18.3%. An increasing prevalence of temporary tinnitus with age was present. Most students had a ‘neutral attitude’ towards loud music and the use of hearing protection was minimal (4.7%). The limited use of hearing protection is explained by a logistic regression analysis showing the relations between certain parameters and the use of hearing protection.

Conclusions

Despite the very high prevalence of tinnitus in such a young population, the rate of hearing protection use and the knowledge about the risks of loud music is extremely low. Future preventive campaigns should focus more on tinnitus as a warning signal for noise-induced damage and emphasize that also temporary symptoms can result in permanent noise-induced damage.

Facing the music: pre- and postconcert assessment of hearing in teenagers

OBJECTIVE

Determine the effect of exposure to a single rock/pop concert on pure-tone hearing thresholds and outer hair cell function in teenagers.

STUDY DESIGN

Repeated measures pre- and postconcert assessment of hearing.

SETTING

Mobile hearing conservation test vehicle and large indoor concert venue.

SUBJECTS

Twenty-nine normal-hearing teenagers and young adults ages 13 to 20 years.

INTERVENTION

Attendance at a public rock/pop concert.

MAIN OUTCOME MEASURES

Pre- and postconcert pure-tone thresholds in both ears from 500 Hz to 8 kHz, pure-tone average (PTA) for 2, 3, and 4 kHz, distortion product otoacoustic emissions (DPOAEs), proportion of subjects experiencing a PTA change of 10 dB or greater.

RESULTS

Concert sound levels at the subjects' position averaged 98.5 dBA. Only 3 subjects used the hearing protection provided. Thresholds for 2 to 6 kHz increased significantly from pre- to postconcert (p ≤ 0.001). The increase in PTA (2, 3, and 4 kHz) between test intervals averaged 6.3 and 6.5 dB for the right and left ears, respectively, and 33.3% of subjects had a threshold shift of 10 dB or greater in the PTA in at least 1 ear (p ≤ 0.001). The number of subjects experiencing a reduction in DPOAE amplitude (17/25) and the change in mean amplitude were statistically significant (p ≤ 0.001 and p ≤ 0.004, respectively).

CONCLUSION

Exposure to a single live-music rock/pop concert can produce a threshold shift and decrease in otoacoustic emissions amplitude indicating impact on outer hair cell function. Results clearly indicate a need for research on this public health issue regarding "safe" listening levels, especially in younger people with more years for accrual of damage.

Trauma-associated tinnitus: audiological, demographic and clinical characteristics

Background

Tinnitus can result from different etiologies. Frequently, patients report the development of tinnitus after traumatic injuries. However, to which extent this specific etiologic factor plays a role for the phenomenology of tinnitus is still incompletely understood. Additionally, it remains a matter of debate whether the etiology of tinnitus constitutes a relevant criterion for defining tinnitus subtypes.

Objective

By investigating a worldwide sample of tinnitus patients derived from the Tinnitus Research Initiative (TRI) Database, we aimed to identify differences in demographic, clinical and audiological characteristics between tinnitus patients with and without preceding trauma.

Materials

A total of 1,604 patients were investigated. Assessment included demographic data, tinnitus related clinical data, audiological data, the Tinnitus Handicap Inventory, the Tinnitus Questionnaire, the Beck Depression Inventory, various numeric tinnitus rating scales, and the World Health Organisation Quality of Life Scale (WHOQoL).

Results

Our data clearly indicate differences between tinnitus patients with and without trauma at tinnitus onset. Patients suffering from trauma-associated tinnitus suffer from a higher mental burden than tinnitus patients presenting with phantom perceptions based on other or unknown etiologic factors. This is especially the case for patients with whiplash and head trauma. Patients with posttraumatic noise-related tinnitus experience more frequently hyperacousis, were younger, had longer tinnitus duration, and were more frequently of male gender.

Conclusions

Trauma before tinnitus onset seems to represent a relevant criterion for subtypization of tinnitus. Patients with posttraumatic tinnitus may require specific diagnostic and therapeutic management. A more systematic and – at best - standardized assessment for hearing related sequelae of trauma is needed for a better understanding of the underlying pathophysiology and for developing more tailored treatment approaches as well.

The comparison of acoustic and psychic parameters of subjective tinnitus

We aim to assess the correlation between audiometric data, and psychotic and acoustic measures associated with subjective tinnitus (ST) and to clarify the importance of the psychological process in determining the degree of subjective annoyance and disability due to tinnitus. Fifty-four patients experiencing unilateral ST were allocated for the study. Acoustic assessment of patients including LDL (loudness discomfort levels), MML (minimum masking level) and RI (residual inhibition) was performed. Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI) and Visual Analog Scale (VAS) tests were performed for the psychological aspects of subjective annoyance. RI was positive in 23 patients with 13 frequency-matched stimuli at 8,000 Hz. Masking treatment response was successful in 16 RI-positive patients. Mean and standard deviation (SD) of THI scores were 38.77 ± 23.63. Ten patients (%18.51) with tinnitus had ≥ 17 points score, which was significant for BDI. Mean and SD were 5.01 ± 2.31 for VAS-1 scores (severity of tinnitus), 7.98 ± 2.79 for VAS-2 (frequency and duration of tinnitus), 5.77 ± 2.72 for VAS-3 (discomfort level), 3.56 ± 3.30 for VAS-4 (attention deficit) and 3.31 ± 3.31 for VAS-5 (sleep disorders). A significant correlation was found between the tinnitus duration time, age, gender and THI scores (P < 0.05). There were statistically significant correlations between VAS 1, 2, 3 scores and LDL, MML and RI (P > 0.05). RI might be largely frequency dependent and was found as an indicator for the masking treatment response. We did not notice statistically significant correlations between audiometric data and THI and BDI. There were correlations between with VAS and LDL and with MML and RI. VAS was simpler and easier for the assessment of ST. We should consider the psychological aspects of ST and assess it as a symptom separately with acoustic and psychotic tests.

Queixas auditivas de disc jockeys da cidade de Recife

OBJETIVO: investigar a ocorrência de queixas auditivas em disc jockeys da cidade de Recife/PE. MÉTODOS: foi realizada uma entrevista com 30 disc jockeys, com idade entre 19 e 28 anos, abordando informações ocupacionais, conhecimentos gerais sobre o ruído e queixas auditivas (diminuição da acuidade auditiva, desconforto a sons intensos, zumbido, sensação de ouvido abafado e otalgia). A análise foi realizada por meio de abordagem quantitativa, utilizando o teste estatístico t-student. RESULTADOS: dentre os dados mais relevantes, destacam-se: 46,7% dos disc jockeys apresentaram, espontaneamente, queixas auditivas, em especial, a diminuição da acuidade auditiva (relatada por todos os sujeitos); 14 disc jockeys (46,67%) referiram desconforto a sons intensos e 13 (43,33%) mencionaram zumbido. Todos afirmaram ter conhecimento sobre os riscos do ruído para a saúde auditiva, mas 76,7% não realizam qualquer medida preventiva de suas consequências. A perda auditiva foi referida pelos sujeitos como o principal risco da exposição a níveis intensos de pressão sonora. CONCLUSÃO: todos os disc jockeys apresentaram queixa de perda auditiva e, entre as demais queixas auditivas, destacaram-se o desconforto a sons intensos e o zumbido. Tendo em vista a irreversibilidade da perda auditiva induzida por elevados níveis de pressão sonora, os disc jockeys devem ser periodicamente avaliados a fim de que se confirme ou não a perda auditiva de que se queixaram e, caso ela exista, deve ser monitorada para que seja passível de intervenção pelo fonoaudiólogo. Desta forma, percebe-se a necessidade de atuação da Fonoaudiologia junto aos disc jockeys, uma vez que poder-se-á propiciar a otimização do exercício profissional com o mínimo de risco possível.