Key Takeaways:

1. Preventable Causes: Childhood infections such as rubella, mumps, and meningitis are significant yet preventable causes of hearing loss, particularly in low-resource settings.
2. Evidence Gaps: Despite identifying 26 hearing-loss-related pathogens, only nine studies met criteria for assessing vaccine impact, revealing a major gap in empirical data and geographic coverage.
3. Policy Implications: Recognizing hearing loss prevention as an added benefit of vaccination could support stronger immunization efforts and reduce vaccine hesitancy globally.

Over 1.5 billion people worldwide are affected by some degree of hearing loss. While it is often linked to aging, a lesser-known but significant cause is infections contracted during childhood and adolescence, many of which are preventable.

This is particularly true in low- and middle-income countries, where access to hearing care is often limited. According to the World Health Organization, nearly 60% of childhood hearing loss could be prevented through public health measures such as vaccination against rubella and certain forms of meningitis.

Statistics like these led a team of researchers, including several from Université de Montréal’s School of Public Health (EPSUM), to conduct an in-depth review of the scientific literature exploring the role vaccination could play in preventing hearing loss in children and adolescents. The results of the review are published in Communications Medicine. 

The team included Mira Johri, a professor in the Department of Health Management, Evaluation and Policy at ESPUM; Shoghig Téhinian, a professional doctorate candidate at ESPUM; Myriam Cielo Pérez Osorio, a public health researcher at Quebec’s Integrated Health and Social Services Centre for Montérégie-Ouest; Enis Barış, a professor at the University of Washington; and Brian Wahl, a professor at the Yale School of Public Health.

26 Pathogens

The researchers conducted an extensive review of the literature to map existing knowledge on the relationship between vaccination and hearing loss prevention.

“It was an extremely detailed review because we looked at the pathogens one by one,” explains Téhinian. “We identified the available vaccines, their mechanisms of action, and what is known about their impact on hearing.”

The research team identified 26 infectious agents that can potentially cause hearing loss, including the virus responsible for common diseases such as measles as well as rubella, which is especially dangerous if contracted during pregnancy because it can harm the developing auditory system and cause congenital deafness.

Also on the list are the virus that causes mumps, which can lead to sensorineural hearing loss by damaging the inner ear or auditory nerve, and the bacteria Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis, which cause meningitis and result in permanent hearing damage.

Gaps in the Research

The researchers found a glaring lack of empirical data on the protective effects of vaccines against hearing loss. Of the thousands of scientific articles identified as relevant, only nine published over the past 40 years met the criteria for inclusion in the new analysis.

Moreover, these nine studies covered just three infectious agents—rubella, mumps and pneumococcus—and were conducted exclusively in high-income countries, such as Sweden, Finland, the Netherlands, the United States, Australia and Japan.

“If a vaccine is shown to save lives, it’s reasonable for policy decisions to be made on that basis,” says Johri. “But vaccines can also offer significant benefits in preventing other harms, such as hearing loss, and these benefits deserve greater attention.”

The design of clinical trials can obscure these additional benefits: since their primary goal is to demonstrate effectiveness against the target disease, the prevention of side effects such as hearing loss is rarely evaluated systematically.

Some Clear Evidence

The nine empirical studies that did examine linkages between vaccines and hearing loss prevention had mixed results. Some found that vaccination can provide protection while others showed no effect. Additionally, the methods used to measure hearing loss varied considerably, making direct comparisons difficult.

Population-level studies show that rubella and mumps vaccination significantly reduces rates of deafness associated with these diseases. In Australia, for instance, the introduction of a rubella vaccination program led to a marked decline in cases of congenital deafness.

In Sweden, the implementation of an MMR (measles, mumps, and rubella) vaccination program was associated with a significant reduction in hearing problems among children. Studies on mumps in Japan and the United States also highlight the importance of vaccination in preventing hearing loss caused by this infection.

On the other hand, three clinical trials evaluating the efficacy of pneumococcal vaccines in preventing middle ear infections (serous otitis media) found no significant reduction in infection rates. The authors point out, however, that serous otitis media is not a direct indicator of permanent hearing loss.

Expanding Vaccine Access

The researchers believe that raising awareness of the hearing-related benefits of vaccination could help strengthen existing immunization programs—especially in low- and middle-income countries, where vaccination coverage is still inadequate.

“If vaccination against measles, for example, is already recommended to reduce mortality, the fact that it can also prevent hearing loss could be highlighted as an additional benefit,” explains Johri. “This could bolster the case for adopting a universal vaccination program.”

The study recommends including the effect on hearing loss in vaccine evaluations, both during development and for products already on the market. This factor could also help inform research priorities for new vaccine formulations.

“These indirect benefits of vaccination need to be better documented and communicated to the public,” says Téhinian. “It could help reduce vaccine hesitancy.”

“Our School of Public Health is located very close to the former Montreal Institute for the Deaf and Mute,” Johri points out. “Only a few decades ago, there were so many children with hearing loss that we needed a dedicated facility for them. Now, thanks to antibiotics and vaccines, fewer people in Canada are affected by hearing loss. This is a success story that could be replicated around the world.”

Featured image: Dreamstime

Key Takeaways:

1. PedsHEAR uses readily available clinical data to predict hearing loss risk with 95% accuracy, offering a new level of individualized care.
2. The model was trained and validated using data from over 1,400 patients across North America, ensuring broad applicability and reliability.
3. This predictive tool marks a major shift in pediatric oncology, allowing doctors to tailor interventions like hearing monitoring or STS use based on each child’s specific risk.

The powerful chemotherapy drug cisplatin has been used since the late 1970s to treat a variety of cancers. It’s highly effective against solid tumors and is often a core element of treatment for children with brain and spinal cord tumors, neuroblastoma, and rhabdomyosarcoma.

Yet, cisplatin is well known to cause devastating side effects. In children, the most common side effect following therapy is debilitating hearing loss. Depending on the treatment plan, up to 80% of children treated with cisplatin end up with permanent hearing loss that affects their social lives, school performance, and future careers. 

Now, an international team led by Etan Orgel, MD, at Children’s Hospital Los Angeles has developed a novel machine learning model that can predict an individual child’s risk of developing hearing loss from cisplatin treatment. Called PedsHEAR, the tool uses routine, readily available information to quickly predict this risk—with 95% confidence.

The team, which includes researchers from the Keck School of Medicine of USC and other institutions across the U.S. and Canada, is the first to develop and validate a novel machine learning model for this purpose. 

Results were published in the Journal of Clinical Oncology, and the model is now available for public use.

A Decades-Long Journey to Personalize Care

The study grew out of two decades of efforts to try to prevent cisplatin-induced hearing loss in children. Investigators from CHLA led the pivotal phase 3 Children’s Oncology Group trial of sodium thiosulfate (STS), and in 2022, the Food and Drug Administration approved STS as the first treatment to reduce the risk of hearing loss in children given cisplatin.

But patients’ treatment regimens are already highly complex, and some may not need STS to prevent hearing loss. For those who are not eligible for STS, it’s critical for clinicians to understand each patient’s risk and what options they have to protect that child’s hearing.  

“We want to give families and providers the tools they need to understand their child’s risk and make an informed decision,” explains Dr Orgel, who directs Quality and Patient Safety at CHLA’s Cancer and Blood Disease Institute. “This is the paradigm shift we’re aiming for—speaking in certainties for each child versus speaking in generalities by regimen.”

This new predictive model is informed by a landmark study designed and led by Dr Orgel in 2021. Researchers analyzed data from more than 1,400 cisplatin-treated patients across the United States and Canada to establish the first benchmarks for the prevalence of cisplatin-induced hearing loss in children and adolescents.

Researchers used the 1,400-person dataset as the foundation for their model, training it to analyze risk factors and probabilities and accurately predict a child’s risk level for hearing loss. The researchers also brought in two new, real-world data sets from the Children’s Oncology Group and a children’s hospital in Texas to validate the model in other populations. The now publicly available web model provides each patient with a percentage indicating the child’s individual probability of hearing loss.

Machine Learning Approaches

Joshua Millstein, PhD, from the Keck School of Medicine of USC, led the creation and optimization of the highly complex machine learning model.

“We assessed a wide variety of modeling strategies to arrive at our final approach, which combines several machine learning methods, then applies a higher-level model—called an ensemble predictor—to integrate each model’s predictions into a single interpretable result,” he explains. “The main challenges of building the final model involved tuning it, which requires finding the model parameters that would optimize the tool’s performance.”

Recent advancements in ensemble predictor modeling helped the team overcome several challenges that have caused other models to fail in the past. “Ensuring that these models have enough patient data for pattern recognition can be exceedingly tricky when developing solutions for rare childhood cancers,” adds Dr Millstein. “These new statistical techniques empowered us to deliver a more refined output, even with many differences between patients within our cohorts.”

Creating a New Treatment Planning Standard

“My goal is for this to become a routine clinical tool,” says Dr Orgel. “What’s unique about this model is that it only uses routinely available data, so any doctor can use it from day one of diagnosis to plan treatment. 

“Forewarned is forearmed going into chemotherapy,” he adds. “It’s so important to understand the options in front of you—and how to approach potential interventions with planned monitoring, such as frequency and compliance, with hearing testing.”

The research team’s next goal is to expand the model to young adults and adults up to 65 and to integrate genomics to make the model even more powerful.  

“Ultimately, we aim to expand our approach to understand and predict risk for other common side effects of common chemotherapies,” says Dr Orgel. “We want to equip all patients beginning their cancer journey with knowledge that supports meaningful discussions with their doctors on what to expect during and after treatment.”

The National Institute for Occupational Safety and Health announced that nominations for the annual Safe-in-Sound Excellence in Hearing Loss Prevention Awards are being accepted.

Awards are granted in two categories:

• Excellence – recognizes those who go out of their way to ensure safety of employees’ hearing by limiting or eliminating risks from noise exposure in their workplace.
• Innovation – recognizes individuals or organizations for their dedication to fostering and implementing unique advances in the prevention of hearing loss and creating innovative solutions to real workplace hearing loss prevention challenges.

The Safe-in-Sound Excellence in Hearing Loss Prevention Awards are cosponsored by NIOSH, the National Hearing Conservation Association (NHCA), and the Council for Accreditation of Hearing Conservationists (CAOHC).

The deadline to nominate another individual, group, or company is June 8, 2023. For self-nominations, the deadline is August 18, 2023. To learn how to submit a nomination, visit the Safe-in-Sound website.

Previous winners have been recognized for purchasing quieter tools or equipment, regularly checking noise levels, providing effective hearing protection tailored to workers’ needs, conducting careful analysis of the annual hearing test results, trained all workers effectively on noise both on and off the job, controlled noise to the levels recommended by NIOSH, and evaluated their program each year to improve deficiencies.

Winners are invited to receive the award and present their real-world examples at the Annual National Hearing Conference, which will take place this year on February 9, 2024 in Albuquerque, New Mexico.

NIOSH recommends removing hazardous noise from the workplace whenever possible and implementing an effective hearing loss prevention program in those situations where dangerous noise exposures have not yet been controlled or eliminated.

For more information about noise and hearing loss prevention research at NIOSH, click here.

Photo 20283767 © Bobebbesen | Dreamstime.com

By Emily Urry, PhD and Elizabeth Stewart, AuD, PhD

Across a lifespan, an individual’s hearing capacity is influenced by genetic, biological, psychosocial, and environmental factors. These factors can either lead to hearing loss or protect against it.¹ The link between diabetes and hearing capacity hit the headlines in recent years due to the American Diabetes Association (ADA)² and the Centers for Disease Control (CDC) recognizing diabetes as a risk factor for hearing loss. Indeed, as per ADA’s website: “…if you live with diabetes, you are twice as likely to experience hearing loss.” However, in academia, the association between diabetes and hearing loss remains somewhat controversial. Study findings are often weakened by the use of self-reported outcome measures or an incomplete collection of medical history (e.g., noise exposure, medication with ototoxic properties) and confounding factors such as age, sex, duration of diabetes, and smoking.³

Diabetes mellitus occurs when raised blood glucose levels persist because the body cannot produce or use insulin effectively. Diabetes can damage many of the body’s organs, leading to serious complications such as cardiovascular diseases and nerve, kidney, and eye damage.⁴ Both diabetes and hearing loss are age-related and highly prevalent conditions. Specifically, 537 million people live with diabetes worldwide (about one in 10)4 while disabling hearing loss affects 430 million people.⁵ Clarifying their association is essential for enabling evidence-based narratives in clinics and providing holistic and person-centered care—an emerging goal in hearing healthcare.⁶ Thus, a literature search was executed to ensure a systematic identification, assessment, and analysis of high-quality data on the association between hearing loss and diabetes, with the goal of providing an overview of the association.

Methods

Relevant evidence was identified as part of a broader literature search investigating the relationship between hearing loss and metabolic risks of cardiovascular disease (CVD)—including diabetes, obesity, hypertension, and dyslipidemia (e.g., high cholesterol). The initial search yielded 1,093 abstracts, which were screened for relevance to the research question and quality of evidence (Figure 1).

Examples of exclusion criteria used during abstract screening included:

• Papers other than peer-reviewed journal articles (e.g., editorials, opinion papers, technical papers, conference posters, etc.)
• Studies in which hearing status and metabolic risk factors for CVD were not the primary focus of the study
• Studies in which hearing and/or metabolic risk factors for CVD were measured subjectively (e.g., self-report)
• Studies related to treatment of CVD metabolic risk factors
• Studies in children and teenagers
• Studies focused on gestational diabetes

The 77 articles that met the screening criteria were then classified according to the metabolic risk captured by study outcome measures. The relationship between hearing loss and diabetes was the most frequently investigated, with 37 potentially relevant articles.

Due to the high number of diabetes papers, only those examining type 2 diabetes mellitus (T2DM) were included—this type typically developed in older age and is thus the most representative of the target population. Further, the most recent meta-analysis regarding the association between hearing loss and T2DM7 was used as a cornerstone in that the exclusion criteria used by the authors were applied to the present analysis; in addition, all papers covered by the time range of their search (all available papers up to April 2013) were removed.

This resulted in 11 remaining papers regarding the diabetes risk factor and hearing loss. An additional two studies identified during the full-text review were considered relevant, for a total of 13 full-text articles assessed for relevance to the research question. Of these, one article was excluded due to use of self-report for the diabetes measure (not identified during abstract screening), and an additional seven were omitted due to the inclusion of a participant cohort not representative of the population of interest or outcome measures not reflective of hearing status, as measured clinically. Thus, five articles were used to summarize the evidence regarding the association between hearing loss and T2DM.

Findings

Detailed analysis of the remaining five studies led to the following conclusions:

1. T2DM is associated with poorer hearing sensitivity.^7-11
2. Hearing loss is significantly more prevalent in groups with T2DM, compared to groups without diabetes.^7-11 For example, the systematic review and meta-analysis of 18 studies by Akinpelu, Mujica-Mota, and Daniel⁷ showed that overall, the prevalence of hearing loss was nearly twice as high (1.91x) in the diabetes group. Indeed, the prevalence of hearing loss ranged between 44% and 70% for T2DM groups, significantly higher than in control groups (20% to 49%). Interestingly, the authors also found that auditory brainstem response results showed prolonged wave V latencies in the T2DM groups compared to the control groups, suggesting reduced retrocochlear function in individuals with diabetes, relative to those without.⁷
3. Individuals with T2DM are more likely to suffer from mild hearing loss (hearing thresholds 26-40 dB HL)12 at high conventional audiometric frequencies (4-8 kHz) compared to individuals without T2DM.^7,8,10,11 Since this pattern is consistent with the presentation of age-related hearing loss, these results suggest that diabetes may speed up the progression of age-related hearing loss or even induce an earlier-than-usual onset.⁷
4. Preliminary evidence revealed significantly lower distortion product otoacoustic emission (DPOAE) amplitudes in T2DM patients^8,9,11 and pre-T2DM,⁸ relative to non-T2DM controls.

This finding suggests that this quick and easily-administered objective measure of hearing function may be useful in identifying negative effects of T2DM on cochlear and retrocochlear function that are detectable prior to audiometric changes. That is, with further research, OAE testing may be an eligible examination for early identification of hearing impairment in T2DM patients.⁹

Does diabetes cause hearing loss?

The potential causal mechanisms underlying the association between diabetes and hearing loss are still under debate. It could be argued that the increased prevalence of hearing loss in T2DM is simply a correlation due to shared biological processes. However, research in humans and animals suggests that diabetes, which damages other parts of the body (e.g., eyes, kidneys) via small blood vessels and nerve dysfunction, may similarly impair the functioning of the inner ear.³ For example, evidence from at least one human temporal bone study revealed significant thickening of the walls of cochlear blood vessels, as well as atrophy of the stria vascularis and outer hair cell loss—all of which may result in or contribute to hearing impairment in individuals with T2DM compared to non-diabetic controls.¹³

Limitations and future research recommendations

The present literature review revealed insufficient evidence to reliably explain and define the effect of both the duration of diabetes and the sex of patients on the association between T2DM and hearing loss. Since about 17.7 million more men than women are living with diabetes,⁴ it would be important to investigate sex differences in the association between diabetes and auditory function. Further, in order to better understand the link between impaired blood glucose regulation and reduced auditory function more broadly, high-quality longitudinal studies are required. Here, objective hearing and diabetes-related data should be collected over time to elucidate their potential causal relationship, to clarify sub-groups of diabetes patients, particularly at risk of hearing loss, and to identify interventions to reduce said risk.

Clinical implications for audiologists

In adults aged 65 or older, a core patient population in hearing care, an estimated 33% have diabetes.¹⁴ Hearing care professionals should be aware that diabetes increases the risk of developing hearing loss and may accelerate its progression. Therefore, when taking a case history at an initial consultation, a question about diabetes status should be included, as well as any family history of the disease (a significant risk factor for diabetes).⁴ In subsequent sessions, any changes in health status and medication intake should be discussed. More broadly, patients should be encouraged to lead healthy, active lifestyles. Smoking and poor nutrition are risk factors for both T2DM⁴ and hearing loss and should be avoided, while regular physical activity, which improves health and reduces diabetes risk¹⁴, should be promoted. HR

Emily Urry, PhD, is an experienced clinical health scientist whose work focuses on cardio-metabolic health promotion via health behavior change. At Sonova, she runs a program that explores the health challenges of people with hearing loss and ways to address said challenges. Elizabeth Stewart, AuD, PhD, is a senior research audiologist in the Phonak Audiology Research Center (Sonova US). She manages various external study collaborations and supports background research activities relevant to Phonak and other Sonova initiatives.

References

1. World report on hearing. Licence: CC BY-NC-SA 3.0 IGO. In: World Health Organization (WHO); 2021: https://www.who.int/publications/i/item/world-report-on-hearing.
2. American Diabetes Association Professional Practice C, American Diabetes Association Professional Practice C, Draznin B, et al. 4. Comprehensive Medical Evaluation and Assessment of Comorbidities: Standards of Medical Care in Diabetes-2022. Diabetes Care. 2022;45(Suppl 1):S46-S59.
3. Samocha-Bonet D, Wu B, Ryugo DK. Diabetes mellitus and hearing loss: A review. Ageing Res Rev. 2021;71:101423.
4. IDF Diabetes Atlas (10th ed.). In: International Diabetes Federation (IDF); 2021: https://diabetesatlas.org/atlas/tenth-edition/.
5. Deafness and hearing loss. World Health Organization. https://www.who.int/health-topics/hearing-loss#tab=tab_2. Accessed 10 March 2023.
6. Maidment DW, Wallhagen MI, Dowd K, et al. New horizons in holistic, person-centred health promotion for hearing healthcare. Age Ageing. 2023;52(2).
7. Akinpelu OV, Mujica-Mota M, Daniel SJ. Is type 2 diabetes mellitus associated with alterations in hearing? A systematic review and meta-analysis. Laryngoscope. 2014;124(3):767-776.
8. Li J, Zhang Y, Fu X, et al. Alteration of auditory function in type 2 diabetic and pre-diabetic patients. Acta Otolaryngol. 2018;138(6):542-547.
9. Li Y, Liu B, Li J, Xin L, Zhou Q. Early detection of hearing impairment in type 2 diabetic patients. Acta Otolaryngol. 2020;140(2):133-139.
10. Ren H, Wang Z, Mao Z, et al. Hearing Loss in Type 2 Diabetes in Association with Diabetic Neuropathy. Arch Med Res. 2017;48(7):631-637.
11. Ren J, Ma F, Zhou Y, et al. Hearing impairment in type 2 diabetics and patients with early diabetic nephropathy. J Diabetes Complications. 2018;32(6):575-579.
12. Fukushima H, Cureoglu S, Schachern PA, Paparella MM, Harada T, Oktay MF. Effects of type 2 diabetes mellitus on cochlear structure in humans. Arch Otolaryngol Head Neck Surg. 2006;132(9):934-938.
13. Diabetes and older adults. Endocrine Society. https://www.endocrine.org/patient-engagement/endocrine-library/diabetes-and-older-adults. Published January 2022. Accessed 23 February 2023.
14. WHO guidelines on physical activity and sedentary behaviour: at a glance. 2020;Licence: CC BY-NC-SA 3.0 IGO.

A review of classroom noise and teacher health

By Pam Millett, PhD

The detrimental effects of noise on speech perception for a number of different populations (eg, students with hearing loss, English Language learners, students with learning challenges, etc…) have been well documented. However, we should not forget the other ways in which high noise levels may impact student and teacher health and well-being at school. The number of studies on the non-auditory effects of noise continues to grow (see Waye & Van Kempen, 2021 for a review of occupational and community noise effects).¹ There are some interesting differences in the research on non-auditory effects of classroom noise compared to research in other areas (eg, on sleep disturbance or job performance). While there is a small literature on the effects of environmental noise on classroom teachers (see Sargent et al, 1980),² most classroom noise consists of speech, so non-auditory effects of noise may look different for classrooms than for other settings. A second difference is that much of this research has come as a byproduct of reducing the impact of the noise (ie, the implementation of sound field system, or classroom audio distribution systems), where anecdotal comments after the installation of these systems has highlighted problems of which people were previously unaware. Of course, research on sound field systems investigates the effects of improving the classroom listening environment by improving signal-to-noise ratio, rather than investigating the effects of reducing classroom noise. However, we can still find clues there. 

Issues which have been extensively studied in other research on the non-auditory effects of noise (such as annoyance, blood pressure changes, health problems, and stress) have received almost no attention for classroom teachers. This may be related to the fact that classroom noise is “relatively” low in comparison to, for example, construction noise, or to the fact that any annoyance factor may be minimized since the noise source is primarily student voices. In fact, in one study by Kristiansen et al,³ the authors noted that “Noise disturbance attributed to traffic noise and ventilation and machinery in the schools…received very low disturbance ratings from most of the respondents” and found that student talking was the most prevalent and most annoying type of noise. This study indicated that approximately 82% of the teachers reported being exposed to disturbing noise for at least ¼ of the workday, and that annoyance reports regarding noise were highly correlated with reverberation times in classrooms.

Teacher vocal fatigue and absenteeism can be considered an indirect effect of classroom noise, but they are important nonetheless. Teachers are unquestionably at higher risk for vocal problems than other professionals.⁴ Research on teacher absenteeism due to vocal problems suggests that vocal problems may be the most common reason for teacher absenteeism.⁵ The societal cost of voice problems in teachers alone may be of the order of about $2.5 billion annually in the US (Rosow et al, 2016).⁶ While some of the vocal problems in teachers are attributable simply to the amount of talking they do during the school day, high noise levels exacerbate this problem because of the need to project one’s voice over the noise, not just occasionally to get students’ attention, but on an ongoing basis throughout the day.⁷

Vocal effort is related to individual factors such as fatigue, but also to environmental factors such as listener-speaker difference and background noise.⁸ Several studies have theorized that physical education teachers and kindergarten teachers are at highest risk because they teach in the highest noise levels and therefore have more vocal strain.⁹ Unsurprisingly, research has noted that voice power levels are related to room size and reverberation time, such that the same vocal effort will result in lower voice power levels and poorer speech intelligibility in a highly reverberant room (such as a gym) than in a smaller, less reverberant classroom.¹⁰ Bottalico et al (2016)¹¹ measured teacher vocal effort and vocal comfort under a variety of acoustical conditions (including varying room size, reverberation time and background noise consisting of children’s speech babble) and found that vocal effort decreased when measures were put in place to improve the acoustical environment. They concluded that speakers change their vocal effort in response to auditory feedback of their own voices under different acoustical conditions. Mattiske et al (1998),⁴ discussed strategies for the prevention and treatment of vocal problems in teachers and reported that there is surprisingly little research on vocal use and vocal hygiene training programs for teachers. What is more surprising to me, though, is the very meager body of research on the effects of simply improving the acoustical environment of the classroom so that teachers do not have to strain their voices, despite the fact that Roy et al (2002),¹² found that sound field amplification had a greater impact on vocal strain than did teacher hygiene training programs and that teachers using voice amplification reported less voice handicap and voice disorder severity, corroborated by objective acoustic analysis. Sapienza et al (1999),¹³ found that teachers used less vocal effort with a sound field amplification system, while Jonsdottir et al,¹⁴ in a study of teachers and students from both elementary school and college/university classrooms, noted that without amplification, 70% of teachers reported throat discomfort prior to trial of sound field amplification. This decreased to 27% after sound field installation.

The COVID-19 pandemic has offered us an interesting perspective on this approach of addressing vocal problems by improving the acoustical environment. Shekaraiah and Suresh (2021),¹⁵ in a systematic review of the effects of masks on vocal production during the pandemic, reported that masks result in results in increased vocal effort, vocal fatigue, discomfort, and perceived voice problems. However, there has been a decrease in reported vocal problems among teachers during the pandemic with remote learning,¹⁶ which is theorized to be due to decreased background noise levels.

Citation for this article: Millett P. Non-auditory effects of noise in the classroom on teachers. Hearing Review. 2022;29(8):20-21.

References

1. Waye KP, Van Kempen E. Non-auditory effects of noise: An overview of the state of the science of the 2017–2020 period. Paper presented at: 13th ICBEN Congress on Noise as a Public Health Problem; June 14-17, 2021; Stockholm, Sweden.
2. Sargent JW, Gidman MI, Humphreys MA, Utley WA. The disturbance caused to school teachers by noise. Journal of Sound and Vibration. 1980;70(4):557-572.
3. Kristiansen J, Lund SP, Nielsen PM, Persson R, Shibuya H. Determinants of noise annoyance in teachers from schools with different classroom reverberation times. Journal of Environmental Psychology. 2011;31(4):383-392.
4. Mattiske JA, Oates JM, Greenwood KM. Vocal problems among teachers: A review of prevalence, causes, prevention, and treatment. Journal of Voice. 1998;12(4):489-499.
5. Medeiros AMD, Vieira MDT. Work absenteeism due to voice disorders in Brazilian schoolteachers. Cadernos de Saúde Pública.2019;35(Suppl 1):e00171717..
6. Rosow DE, Szczupak M, Saint-Victor S, et al. The economic impact of vocal attrition in public school teachers in Miami-Dade County. The Laryngoscope. 2016;26(3):665-671.
7. Smith E, Lemke J, Taylor M, Kirchner HL, Hoffman H. Frequency of voice problems among teachers and other occupations. Journal of Voice. 1998;12(4):480-488.
8. Pelegrín-García D, Smits B, Brunskog J, Jeong, C-H. Vocal effort with changing talker-to-listener distance in different acoustic environments. The Journal of the Acoustical Society of America. 2011;129(4):1981.
9. Sarfati J. Vocal retraining of teachers. Rev Laryngol. 1989;110(4):393-395.
10. Astolfi A, Bottalico P, Accornero A, et al. Relationship between vocal doses and voice disorders on primary school teachers. Paper presented at: Euronoise 2012; June 10-14, 2012; Prague, Czechoslovakia.
11. Bottalico P, Graetzer S, Hunter EJ. Effects of speech style, room acoustics, and vocal fatigue on vocal effort. The Journal of the Acoustical Society of America. 2016;139(5):2870.
12. Roy N, Weinrich B, Gray SD, et al. Voice amplification versus vocal hygiene instruction for teachers with voice disorders: A treatment outcomes study. Journal of Speech, Language, and Hearing Research. 2002;45(4):625-638. 
13. Sapienza CM, Crandell, CC, Curtis B. Effects of sound-field frequency modulation amplification on reducing teachers’ sound pressure level in the classroom. Journal of Voice.1999;13(3):375-381.
14. Jonsdottir V, Laukkanen A-M, Siikki I. Changes in teachers’ voice quality during a working day with and without electric sound amplification. Folia Phoniatrica et Logopaedica. 2003;55(5):267-280.
15. Shekaraiah S, Suresh K. Effect of face mask on voice production during COVID-19 pandemic: A systematic review. Journal of Voice. September 23, 2021.
16. Patjas M, Vertanen-Greis H, Pietarinen P, Geneid A. Voice symptoms in teachers during distance teaching: A survey during the COVID-19 pandemic in Finland. European Archives of Oto-Rhino-Laryngology. 2021;278:4383-4390.

With an estimated 1.6 billion people affected by hearing loss worldwide, there are a variety of early intervention steps that can be taken to reduce the incidence and severity of loss, according to the authors. For developing countries these steps may include improving sanitation, better prenatal care, reduction of occupational exposure to ototoxic drugs and loud noise, and ensuring vaccinations are up to date. In higher income countries, exposure to loud noise from personal devices among young people remains a preventable risk that is strongly associated with hearing loss, according to the authors, who encourage the promotion of safe listening practices.

Further, the authors recommend low-cost screening apps like the World Health Organization’s (WHO) hearWHO or early detection screenings of children, and the use of sign language, autocaptioning, and other methods to address the needs of those with hearing loss.

As part of a 3-part action plan, the JAMA authors advocate for a coordinated healthcare strategy for hearing loss that incorporates all stakeholders; adaptation of health systems to account for the needs of people with hearing loss that include sign language interpreters, assistive technologies, and quiet environments; and research funding to account for the impact of hearing loss on quality of life and economic productivity (NIH funding for hearing research is currently ranked 20th as of 2017, according to the article).

To read the article in its entirety, please click here.

Source: JAMA Network

According to Wirecutter, all of the headphones tested, which included the Avid AE-36, Califone CA-2, Egghead 1005FAUSB, HamiltonBuhl SchoolMate, Learning Headphones LH-55, and the ThinkWrite TW110 and TW210, produced results ranging from the low 90s to low 100s; according to the Centers for Disease Prevention and Control (CDC), volume at 100 decibels can damage hearing in 15 minutes.

The authors conclude that given the nature of educational programming, which is mainly speech at normal volumes, and the fact that children are not allowed to bring the headphones home, probably pose little risk for “most students with healthy ears.” The amount of time children spend engaging with this kind of media varies depending on the child’s age, grade, and school, according to the article.

To read the article in its entirety, please click here.

Source: Wirecutter, NY Times

In 2020, 71% of production workers suffered moderate levels of noise exposure and about 25 percent endured loud noise levels. In the construction industry, at least 25% of those exposed to noise report hearing loss that impacts their day-to-day activities.  

“Hearing conservation programs are designed to protect workers’ hearing and prevent irreversible hearing loss. These programs also provide employers and workers with the knowledge and equipment to control and reduce their exposure to noise,” said OSHA Acting Regional Administrator Steven J. Kaplan in Kansas City, Missouri. “Our Regional Emphasis Program has an outreach phase that encourages employers to address and correct hazards, followed by targeted inspections to ensure employers are taking necessary steps to reduce noise hazards and prevent injuries to their workers.”

By law, OSHA requires employers to implement a hearing conservation program when the average noise exposure over 8 working hours reaches or exceeds 85 decibels, which the Centers for Disease Control and Prevention (CDC) compares to the sound of city traffic (from inside the vehicle) or a gas-powered leaf blower. To prevent noise-induced hearing loss, OSHA provides employers with hearing conservation guidelines.

In the REP’s initial phase, OSHA will send information to employers, professional associations, local safety councils, apprenticeship programs, local hospitals, and occupational health clinics. Agency representatives will also make presentations to industry organizations and stakeholders. The REP will also encourage employers to use OSHA’s free consultation services to help them implement noise safety strategies and ensure compliance with OSHA standards. 

OSHA encourages employers to take steps to identify, reduce, and eliminate hazards related to high levels of noise during the REP’s initial phase. Following its three-month outreach that began February 28, the REP empowers OSHA to schedule and inspect select general industry and construction employers in Kansas, Missouri, and Nebraska with hearing loss rates higher than the national average. 

Learn more about OSHA.

Source: DOL

Under the theme ‘To hear for life, listen with care!’ WHO has issued a new international standard for safe listening at venues and events. The standard applies to places and activities where amplified music is played. 

“Millions of teenagers and young people are at risk of hearing loss due to the unsafe use of personal audio devices and exposure to damaging sound levels at venues such as nightclubs, bars, concerts, and sporting events,” said Dr Bente Mikkelsen, WHO Director for the Department for Noncommunicable Diseases. 

She added: “The risk is intensified as most audio devices, venues, and events do not provide safe listening options and contribute to the risk of hearing loss. The new WHO standard aims to better safeguard young people as they enjoy their leisure activities.”    

New recommendations to limit risk of hearing loss

The Global Standard for Safe Listening at Venues and Events highlights six recommendations for implementation to ensure that venues and events limit the risk of hearing loss to their patrons while preserving high-quality sound and an enjoyable listening experience. The six recommendations are: 

(1) A maximum average sound level of 100 decibels;

(2) Live monitoring and recording of sound levels using calibrated equipment by designated staff;

(3) Optimizing venue acoustics and sound systems to ensure enjoyable sound quality and safe listening;

(4) Making personal hearing protection available to audiences including instructions on use; 

(5) Access to quiet zones for people to rest their ears and decrease the risk of hearing damage; and 

(6) Provision of training and information to staff.

The new standard was developed under WHO’s Make Listening Safe initiative which seeks to improve listening practices especially among young people, drawing on the latest evidence and consultations with a range of stakeholders including experts from WHO, government, industry, consumers, and civil society.  

Hearing loss due to loud sounds is permanent but preventable

Exposure to loud sounds causes temporary hearing loss or tinnitus. But prolonged or repeated exposure can lead to permanent hearing damage, resulting in irreversible hearing loss. Young people can better protect their hearing by:

• Keeping the volume down on personal audio devices;
• Using well-fitted, and if possible, noise-cancelling earphones/headphones;
• Wearing earplugs at noisy venues;
• Getting regular hearing check-ups.

Advocating for the new global standard

WHO encourages governments to develop and enforce legislation for safe listening and raise awareness of the risks of hearing loss. The private sector should include WHO’s recommendations for safe listening features in their products, venues, and events. To motivate behavior change, civil society organizations, parents, teachers, and physicians can educate young people to practice safe listening habits.

“Governments, civil society, and private sector entities such as manufacturers of personal audio devices, sound systems, and video gaming equipment as well as owners and managers of entertainment venues and events have an important role to play in advocating for the new global standard,” said Dr Ren Minghui, WHO Assistant Director-General. “We must work together to promote safe listening practices, especially among young people.”

Source: WHO

Q: How are heart health and hearing health related?

Normal blood flow is critical for good hearing health. Delicate hair cells in the inner ear (the cochlea) turn sound into electrical impulses that travel to the brain so we can hear speech, music, or noise. Those hair cells rely on good circulation to function properly. Heart disease or hypertension can decrease the blood flow to the inner ear. If those hair cells don’t get enough oxygen, this can permanently damage the hair cells and your hearing over time.

Q: How can people take care of their cardiovascular systems?

It’s all about knowing and decreasing your risk factors. Staying physically active, maintaining a healthy weight, and not smoking are key to good cardiovascular health. You should also know your blood pressure, cholesterol level, and hemoglobin AIC, which is elevated in people with diabetes. If you do have high blood pressure, diabetes, or high cholesterol, make sure you talk to your doctor about taking the right medication and enough medication to get your numbers into a normal range.

By taking care of your cardiovascular system, you’ll also be proactively protecting your hearing. Consider these studies and stats which show cardiovascular risk factors are also associated with hearing loss:

• A new study published in JAMA further confirms that smoking increases the risk of hearing loss.
• Hearing loss is twice as common in people who have diabetes as it is in people of the same age who don’t. Even people with prediabetes (blood sugar levels higher than normal but not high enough yet to have Type 2 diabetes) have a 30% higher rate of hearing loss than people with normal blood sugar levels. 
• Obesity increases the risk of hearing loss .
• Individuals with hearing loss have lower physical activity than those without. 

Q: Can hearing loss be an indicator of issues with cardiovascular health?

It can. The inner ear is small and sensitive and susceptible to changes in blood flow. So, the ear can be one of the first parts of the body to be affected by cardiovascular disease. In fact, about 40% of people with mild or moderate hypertension have hearing loss.

Q: What other health issues are associated with hearing loss?

Hearing loss is strongly associated with dementia. Research from Johns Hopkins shows that mild hearing loss doubles the risk of dementia, while moderate hearing loss triples the risk. Hearing loss also increases the risk of falls and injuries because hearing is an important part of maintaining your balance and equilibrium. People with mild hearing loss are three times more likely to fall and more likely to have an injury when they are working, driving, or just having fun. Finally, people with hearing loss are at high risk for depression and loneliness, because hearing loss leads to being left out of conversations or withdrawing from group interactions altogether. These are all reasons why Starkey is creating Healthable hearing aids, that not only help you hear better but also have embedded sensors and technology to monitor your overall health – including your heart health.

Q: What should someone do if they suspect they have hearing loss?

Don’t procrastinate. Visit a hearing health professional to get your hearing formally tested. They can tell you how severe the hearing loss is and discuss your options. If you aren’t sure whether you have hearing loss, you can do a free online hearing screening test from the privacy of your own home at Starkey.com. Hearing loss is not curable, but it is treatable, and treating it earlier can lead to better outcomes. In fact, researchers are looking at whether earlier use of hearing aids can delay or prevent dementia. If you do need hearing aids, do your research before deciding what hearing aids are right for you. Get the ones that give you the best sound and also have features that make it easy to monitor health and live a healthy lifestyle. 

To learn more about Starkey, please click here.

Source: Starkey