Audiogram configurations among older adults: Prevalence and relation to self-reported hearing problems

Elderly people with hearing loss and cognitive decline: speech perception performance in noise

PURPOSE

To verify the influence of verbal intellectual-cognitive skills on speech perception in noise, in elderly with sensorineural hearing loss, considering education, age, and degree of hearing loss.

METHODS

36 elderly between 60 and 89 years old with bilateral sensorineural hearing loss participated in the study. After psychological assessment using the Wechsler Intelligence Scale for Adults (WAIS-III), they were grouped into (GI) 24 elderly without cognitive alteration and (GII) 12 elderly with risk of cognitive alteration. They underwent otorhinolaryngological assessment, audiological interview, pure tone audiometry, and assessment of speech perception in noise using the Hearing in Noise Test (HINT-Brazil). The Mann-Whitney U statistical test compared the results between the groups, and the Spearman correlation verified the variable's age, degree of hearing loss, and level of education.

RESULTS

There was no difference between the groups in the ability to perceive speech in noise, except in the noise on the left condition, in which GII showed better performance in HINT-Brazil. The degree of hearing loss and level of education influenced the perception of speech in noise. The level of education was correlated with the WAIS-III results.

CONCLUSION

The decline in verbal intellectual-cognitive skills did not affect speech perception of noise in the elderly with hearing loss. The degree of hearing loss and level of education influenced the performance of the elderly in the speech perception test in noise. Performance in verbal cognitive skills varied according to the level of education.

Development and validation of prediction model to estimate vertigo risk after endolymphatic sac decompression in Meniere's disease: a retrospective cohort study

PURPOSE

To study the efficacy predictors of endolymphatic sac decompression (ESD) in Meniere's disease (MD), and to establish and verify the prediction model of vertigo after ESD in patients with MD.

METHODS

The retrospective cohort data of 56 patients with unilateral MD who underwent ESD surgery were recorded. A stepwise regression method was used to select optimal modeling variables, and we established a logistic regression model with the outcome of vertigo after ESD. The bootstrap method was used for internal validation.

RESULTS

Potential predictors included sex, age, follow-up duration, disease course, attack duration, frequency of attack, pure-tone threshold average (PTA) of the patient's speech frequency, audiogram type, glycerin test results, MD subtype, and 10-year atherosclerotic cardiovascular disease risk classification. Using the stepwise regression method, we found that the optimal modeling variables were the audiogram type and PTA of the patient's speech frequency. The prediction model based on these two variables exhibited good discrimination [area under the receiver operating characteristic curve: 0.72 (95% confidence interval: 0.57-0.86)] and acceptable calibration (Brier score 0.21).

CONCLUSION

The present model based on the audiogram type and PTA of the patient's speech frequency was found to be useful in guidance of ESD efficacy prediction and surgery selection.

A history of occupational noise exposure is associated with steep-slope audiograms and poorer self-reported hearing-aid outcomes

OBJECTIVE

To investigate the effects of previous occupational noise exposure in older adults with hearing loss on (1) audiometric configuration and acoustic reflex (AR) thresholds and (2) self-reported hearing abilities and hearing aid (HA) effectiveness.

DESIGN

A prospective observational study.

STUDY SAMPLE

The study included 1176 adults (≥60 years) with bilateral sensorineural hearing loss. Pure-tone audiometry, AR thresholds, and responses to the abbreviated version of the Speech, Spatial, and Qualities of Hearing Scale (SSQ12) and the International Outcome Inventory for Hearing Aids (IOI-HA) questionnaire were obtained, along with information about previous occupational noise exposure.

RESULTS

Greater occupational noise exposure was associated with a higher prevalence of steeply sloping audiograms in men and women and a 0.32 (95% CI: -0.57; -0.06) scale points lower mean SSQ12 total score among noise-exposed men. AR thresholds did not show a significant relation to noise-exposure status, but hearing thresholds at a given frequency were related to elevated AR thresholds at the same frequency.

CONCLUSIONS

A noise exposure history is linked to steeper audiograms in older adults with hearing loss as well as to poorer self-reported hearing abilities in noise-exposed men. More attention to older adults with previous noise exposure is warranted in hearing rehabilitation.

The effect of vascular risk factors on the efficacy of endolymphatic sac decompression surgery for Meniere's disease: a retrospective cohort study

Objectives

This study aimed to investigate the effect of vascular risk factors on the outcomes of endolymphatic sac decompression (ESD) surgery in patients with Meniere's disease.

Methods

The study included 56 patients with Meniere's disease, who had undergone unilateral ESD surgery. The patients' vascular risk factors were assessed based on the preoperative 10-year atherosclerotic cardiovascular diseases risk classification. Those with no or low risk were defined as the low-risk group, while those with medium, high, or very high risk were defined as the high-risk group. The correlation between the vascular risk factors and ESD efficacy was evaluated by the comparison of vertigo control grade between the two groups. The functional disability score was also assessed to investigate whether ESD improved the quality of life in Meniere's disease patients with vascular risk factors.

Results

After ESD, 78.95 and 81.08% of patients from the low-risk and high-risk groups, respectively, demonstrated at least grade B vertigo control; no statistically significant difference was observed (p = 0.96). The postoperative functional disability scores in both groups were significantly lower compared with those before surgery (p < 0.01), with a median decrease of two (1, 2) points in both groups. No statistically significant difference between the two groups was observed (p = 0.65).

Conclusion

Vascular risk factors have little effect on the efficacy of ESD in patients with Meniere's disease. Patients with one or more vascular risk factors can still experience a not poor vertigo control and improved quality of life after ESD.

Analysis of sensorineural hearing loss in patients attending an otolaryngology clinic in North Central Nigeria

Hearing loss is the third leading cause of years lived with disability. Approximately 1.4 billion people have hearing loss, of which 80% reside in low- and middle-income countries with limited audiology and otolaryngology care available to them. The objective of this study was to estimate period prevalence of hearing loss and audiogram patterns of patients attending an otolaryngology clinic in North Central Nigeria. A 10-year retrospective cohort study was carried out analyzing 1507 patient records of pure tone audiograms of patients at the otolaryngology clinic at Jos University Teaching Hospital, Plateau State, Nigeria. Prevalence of hearing loss of moderate or higher grade increased significantly and steadily after age 60. Compared to other studies, there was a higher prevalence of overall sensorineural hearing loss (24-28% in our study compared to 1.7-8.4% globally) and higher proportions of the flat audiogram configuration among the younger age patients (40% in younger patients compared to 20% in patients older than 60 years). The higher prevalence of the flat audiogram configuration compared to other parts of the world may be suggestive of an etiology specific to this region, such as the endemic Lassa Fever and Lassa virus infection in addition to cytomegalovirus or other viral infections associated with hearing loss.

Inner-hair-cell induced hearing loss: A biophysical modeling perspective

In recent years, experimental studies have demonstrated that malfunction of the inner-hair cells and their synapse to the auditory nerve is a significant hearing loss (HL) contributor. This study presents a detailed biophysical model of the inner-hair cells embedded in an end-to-end computational model of the auditory pathway with an acoustic signal as an input and prediction of human audiometric thresholds as an output. The contribution of the outer hair cells is included in the mechanical model of the cochlea. Different types of HL were simulated by changing mechanical and biochemical parameters of the inner and outer hair cells. The predicted thresholds yielded common audiograms of hearing impairment. Outer hair cell damage could only introduce threshold shifts at mid-high frequencies up to 40 dB. Inner hair cell damage affects low and high frequencies differently. All types of inner hair cell deficits yielded a maximum of 40 dB HL at low frequencies. Only a significant reduction in the number of cilia of the inner-hair cells yielded HL of up to 120 dB HL at high frequencies. Sloping audiograms can be explained by a combination of gradual change in the number of cilia of inner and outer hair cells along the cochlear partition from apex to base.

Neural signatures of auditory hypersensitivity following acoustic trauma

Neurons in sensory cortex exhibit a remarkable capacity to maintain stable firing rates despite large fluctuations in afferent activity levels. However, sudden peripheral deafferentation in adulthood can trigger an excessive, non-homeostatic cortical compensatory response that may underlie perceptual disorders including sensory hypersensitivity, phantom limb pain, and tinnitus. Here, we show that mice with noise-induced damage of the high-frequency cochlear base were behaviorally hypersensitive to spared mid-frequency tones and to direct optogenetic stimulation of auditory thalamocortical neurons. Chronic two-photon calcium imaging from ACtx pyramidal neurons (PyrNs) revealed an initial stage of spatially diffuse hyperactivity, hyper-correlation, and auditory hyperresponsivity that consolidated around deafferented map regions three or more days after acoustic trauma. Deafferented PyrN ensembles also displayed hypersensitive decoding of spared mid-frequency tones that mirrored behavioral hypersensitivity, suggesting that non-homeostatic regulation of cortical sound intensity coding following sensorineural loss may be an underlying source of auditory hypersensitivity. Excess cortical response gain after acoustic trauma was expressed heterogeneously among individual PyrNs, yet 40% of this variability could be accounted for by each cell's baseline response properties prior to acoustic trauma. PyrNs with initially high spontaneous activity and gradual monotonic intensity growth functions were more likely to exhibit non-homeostatic excess gain after acoustic trauma. This suggests that while cortical gain changes are triggered by reduced bottom-up afferent input, their subsequent stabilization is also shaped by their local circuit milieu, where indicators of reduced inhibition can presage pathological hyperactivity following sensorineural hearing loss.

How Does the "Cookie-Bite" Audiogram Shape Perform in Discriminating Genetic Hearing Loss in Adults?

"Cookie-bite" or U-shaped audiograms-specifically, those showing midfrequency sensorineural hearing loss (HL)-are traditionally taught to be associated with genetic HL; however, their utility as a screening tool has not been reported. We aim to determine the performance of a cookie-bite audiogram shape in stratifying patients carrying putative loss-of-function variants in known HL genes from wild-type controls. We merged audiometric and exome sequencing data from adults enrolled in a large biobank at a tertiary care center. Of 321 patients, 50 carried a putative loss-of-function variant in an HL gene. The cookie-bite shape was present in 9 of those patients, resulting in low sensitivity (18%) and positive predictive value (15%) in stratifying genetic carrier status; 84% of patients with a cookie-bite audiogram did not carry a genetic variant. A cookie-bite audiogram should not be used to screen adults for possible genetic testing.

Prevalence and incidence of hearing impairment among adults: a 13-year follow-up study

OBJECTIVE

The aim of this study was to investigate the prevalence and incidence of hearing impairment (HI) in a longitudinal setting among adults.

DESIGN

An unscreened, population-based epidemiological 13-year follow-up study. Study sample: 850 randomly sampled 54 to 66-year-old baseline participants, of whom 559 participated in the follow-up study at the age of 68 to 79 years. A questionnaire-based interview, an otological examination and pure-tone audiometry were performed.

RESULTS

The overall prevalence of HI was 70.3%, defined by better ear hearing level (BEHL)  ≥ 20 dB in the 0.5-4 kHz frequency range. The prevalence was higher among men (78.6%) than among women (63.7%). The overall incidence rate for HI was 45.8 per 1000 person years and the 13-year cumulative incidence was 60.9%. The incidence was higher among men and older participants.

CONCLUSION

HI is highly prevalent and incident among older adults in Northern Finland.

Hearing examinations in Southern Denmark (HESD) database: a valuable tool for hearing-related epidemiological research

OBJECTIVE

To introduce and document the recently established HESD (Hearing Examinations in Southern Denmark) database, including the necessary data preprocessing steps, and to describe the hearing loss (HL) characteristics of the study sample.

DESIGN

Clinical auditory information has been collected for approximately 20 years in the state-funded clinics of the Region of Southern Denmark. We reviewed these data and conducted extensive preprocessing through data selection, integration, cleaning, transformation, and classification. HL profiling was then assessed in terms of severity, asymmetry, configuration, site of lesion, and audiogram shape.

STUDY SAMPLE

The final number of complete audiograms available in the HESD database was 271,556, corresponding to detailed hearing information for 143,793 adults.

RESULTS

The distribution of HL characteristics differed significantly (p < 0.001) between men and women for all categories analysed. Clear differences were observed for asymmetry and audiogram configuration. However, both men and women had higher prevalence of unilateral, moderate, and sensorineural HL.

CONCLUSIONS

This work highlights the potential of the HESD database as a source of audiology-related epidemiological data. It can be used to evaluate the distribution of HL characteristics and also to investigate risk factors for HL and the associations between HL and other health outcomes.

A Novel Method for Classifying Hearing Impairment in Epidemiological Studies of Aging: The Wisconsin Age-Related Hearing Impairment Classification Scale

Purpose Longitudinal population-based cohort data were used to develop a standardized classification system for age-related hearing impairment using thresholds for frequencies (0.5-8 kHz) typically measured in cohort studies. Method Audiometric testing data collected in the Epidemiology of Hearing Loss Study from participants (n = 1,369) with four visits (1993-1995, 1998-2000, 2003-2005, and 2009-2010) were included (10,952 audiograms). Cluster analyses (Wald's method) were used to identify audiometric patterns. Maximum allowable threshold values were defined for each cluster to create an ordered scale. Progression was defined as a two-step change. Results An eight-step scale was developed to capture audiogram shape and severity of hearing impairment. Of the 1,094 participants classified as having normal hearing based on a pure-tone average, only 25% (n = 277) were classified as Level 1 (all thresholds ≤ 20 dB HL) on the new scale, whereas 17% (n = 182) were Levels 4-6. During the 16-year follow-up, 64.9% of those at Level 1 progressed. There was little regression using this scale. Conclusions This is the first scale developed from population-based longitudinal cohort data to capture audiogram shape across time. This simple, standardized scale is easy to apply, reduces misclassification of normal hearing, and may be a useful method for identifying risk factors for early, preclinical, age-related changes in hearing.

Data-Driven Audiogram Classification for Mobile Audiometry

Recent mobile and automated audiometry technologies have allowed for the democratization of hearing healthcare and enables non-experts to deliver hearing tests. The problem remains that a large number of such users are not trained to interpret audiograms. In this work, we outline the development of a data-driven audiogram classification system designed specifically for the purpose of concisely describing audiograms. More specifically, we present how a training dataset was assembled and the development of the classification system leveraging supervised learning techniques. We show that three practicing audiologists had high intra- and inter-rater agreement over audiogram classification tasks pertaining to audiogram configuration, symmetry and severity. The system proposed here achieves a performance comparable to the state of the art, but is significantly more flexible. Altogether, this work lays a solid foundation for future work aiming to apply machine learning techniques to audiology for audiogram interpretation.

Auditory function and prevalence of specific ear and hearing related pathologies in the general population at age 70

Objective: To describe the auditory function in early old age in detail based on both psychoacoustic and physiological measures, and to investigate the prevalence of specific audiological and otological pathologies.Design: An unscreened subsample from a population-based geriatric investigation was examined with otoscopy; tympanometry; pure-tone audiometry; word-recognition-in-noise test; distortion-product otoacoustic emissions; and auditory-evoked brainstem responses. Audiometric subtypes and diagnoses were established based on set criteria. The association between word scores and ABR was examined with linear regression analysis.Study Sample: 251 persons aged 70 (113 men, 138 women, born in 1944) that were representative of the inhabitants of the city of Gothenburg.Results: The prevalence of conductive pathology was 2% versus 49% for cochlear and 2% for auditory-neural pathology. Four percent had indeterminate type. Cochlear dysfunction was present in the majority of ears and around 20% performed worse-than-expected on speech testing. Poor performance on the speech in noise test was associated with prolonged interpeak latency interval of ABR waves I-V.Conclusion: Specific otological and audiological pathologies, other than cochlear hearing loss, are rare in the general population at age 70. Additionally, there is subtle evidence of age-related decline of the auditory nerve. Longitudinal follow-up would be of great interest.

Spatial release from informational masking declines with age: Evidence from a detection task in a virtual separation paradigm

Declines in spatial release from informational masking may contribute to the speech-processing difficulties that older adults often experience within complex listening environments. The present study sought to answer two fundamental questions: (1) Does spatial release from informational masking decline with age and, if so, (2) does age predict this decline independently of age-typical hearing loss? Younger (18-34 years) and older (60-80 years) adults with age-typical hearing completed a yes/no target-detection task with low-pass filtered noise-vocoded speech designed to reduce non-spatial segregation cues and control for hearing loss. Participants detected a target voice among two-talker masking babble while a virtual spatial separation paradigm [Freyman, Helfer, McCall, and Clifton, J. Acoust. Soc. Am. 106(6), 3578-3588 (1999)] was used to isolate informational masking release. The younger and older adults both exhibited spatial release from informational masking, but masking release was reduced among the older adults. Furthermore, age predicted this decline controlling for hearing loss, while there was no indication that hearing loss played a role. These findings provide evidence that declines specific to aging limit spatial release from informational masking under challenging listening conditions.

Análise comparativa dos métodos prescritivos NAL-NL2 e DSL v5.0a na adaptação do AASI em idosos

RESUMO Objetivo Analisar comparativamente os métodos prescritivos NAL-NL2 e DSL v5.0a de acordo com programação individualizada do AASI para o indivíduo idoso com deficiência auditiva. Método Participaram do estudo 60 indivíduos idosos com deficiência auditiva, submetidos à mensuração da RECD (Real Ear to Coupler Difference) e programação individualizada do AASI com os métodos prescritivos NAL-NL2 e DSL v5.0a. A verificação do desempenho com cada prescrição foi realizada por meio das medidas da REAR (Real Ear Aided Response), cálculo do SII (Speech Intelligibility Index) e teste HINT (Hearing In Noise Test). A análise estatística comparativa foi realizada por meio do teste “t” pareado. Resultados O método NAL-NL2 apresentou melhor desempenho na avaliação da REAR em frequências baixas e altas para sons de média e forte intensidade, em frequências altas para sons de fraca intensidade, e no cálculo do SII para sons fracos. O método DSL v5.0a apresentou melhores resultados na avaliação da REAR em frequências médias para sons médios, em frequências baixas e médias para sons fracos, no cálculo do SII para sons médios e fortes, e no teste HINT no silêncio e ruído. Conclusão Os achados deste estudo apontam para um desempenho equivalente entre os métodos DSL v5.0a e NAL-NL2 na adaptação do AASI em idosos com deficiência auditiva. A amplificação calculada pela DSL v5.0a forneceu melhor percepção de fala no silêncio.

Impact of indian public health standards for rural health care facilities on national programme for control of deafness in India: The results of a cohort study

Introduction:

In National Programme for Prevention and Control of Deafness (NPPCD), the management of ear diseases of rural India is now guided by Revised Indian Public Health Standards (IPHS) for Rural Health Facilities for providing quality ear care. However, despite the IPHS existence, coverage and quality ear care is questionable. Moreover, this issue has not yet been studied till now in the Indian context. The objective of the study was to assess the role of Private Medical College Training Center (Rural Health Training Centre [RHTC]) in augmenting quality of ear care services in NPPCD at district level by adopting IPHS Standards.

Materials and Methods:

A combined retrospective and prospective cohort study was done at RHTC of a Medical College in West Uttar Pradesh from January 1, 2013, to December 31, 2017, by retrospective approach of selecting all ear patients (n = 3840) and prospective way of assessing the impact of IPHS for ear care. The semi-structured Pro forma was used in exploring the coverage and quality of ear care. The data were analyzed by Epi Info version 7.2.

Results:

Out of total 4817 ear, nose, and throat (ENT) patients, the majority of ear patients (n = 3840) were initially dissatisfied with coverage and quality of ear services provided by ENT specialists at RHTC. However, when IPHS exposure was given from July 1, 2015 to December 31, 2017, not only majority of patients were satisfied (n = 3110, 81%) but also ear curative treatment was significantly higher (n = 2120, 68.1% vs. n = 130, 17.8%, odds ratio = 9.8, RR = 1.5, P < 0.00001).

Conclusions:

Adherence to IPHS in NPPCD is essential for delivering better ear care by RHTC through primary health-care approach.

Logistic regression analysis of factors influencing the effectiveness of intensive sound masking therapy in patients with tinnitus

OBJECTIVES

To investigate factors influencing the effectiveness of intensive sound masking therapy on tinnitus using logistic regression analysis.

DESIGN

The study used a retrospective cross-section analysis.

PARTICIPANTS

102 patients with tinnitus were recruited at the Sun Yat-sen Memorial Hospital of Sun Yat-sen University, China.

INTERVENTION

Intensive sound masking therapy was used as an intervention approach for patients with tinnitus.

PRIMARY AND SECONDARY OUTCOME MEASURES

Participants underwent audiological investigations and tinnitus pitch and loudness matching measurements, followed by intensive sound masking therapy. The Tinnitus Handicap Inventory (THI) was used as the outcome measure pre and post treatment. Multivariate logistic regression was performed to investigate the association of demographic and audiological factors with effective therapy.

RESULTS

According to the THI score changes pre and post sound masking intervention, 51 participants were categorised into an effective group, the remaining 51 participants were placed in a non-effective group. Those in the effective group were significantly younger than those in the non-effective group (P=0.012). Significantly more participants had flat audiogram configurations in the effective group (P=0.04). Multivariable logistic regression analysis showed that age (OR=0.96, 95% CI 0.93 to 0.99, P=0.007), audiometric configuration (P=0.027) and THI score pre treatment (OR=1.04, 95% CI 1.02 to 1.07, P<0.001) were significantly associated with therapeutic effectiveness. Further analysis showed that patients with flat audiometric configurations were 5.45 times more likely to respond to intervention than those with high-frequency steeply sloping audiograms (OR=5.45, 95% CI 1.67 to 17.86, P=0.005).

CONCLUSION

Audiometric configuration, age and THI scores appear to be predictive of the effectiveness of sound masking treatment. Gender, tinnitus characteristics and hearing threshold measures do not seem to be related to treatment effectiveness. A further randomised control study is needed to provide evidence of the effectiveness of prognostic factors in tinnitus interventions.

A nonsynonymous mutation in the WFS1 gene in a Finnish family with age-related hearing impairment

Wolfram syndrome (WS) is caused by recessive mutations in the Wolfram syndrome 1 (WFS1) gene. Sensorineural hearing impairment (HI) is a frequent feature in WS and, furthermore, certain mutations in WFS1 cause nonsyndromic dominantly inherited low-frequency sensorineural HI. These two phenotypes are clinically distinct indicating that WFS1 is a reasonable candidate for genetic studies in patients with other phenotypes of HI. Here we have investigated, whether the variation in WFS1 has a pathogenic role in age-related hearing impairment (ARHI). WFS1 gene was investigated in a population sample of 518 Finnish adults born in 1938-1949 and representing variable hearing phenotypes. Identified variants were evaluated with respect to pathogenic potential. A rare mutation predicted to be pathogenic was found in a family with many members with impaired hearing. Twenty members were recruited to a segregation study and a detailed clinical examination. Heterozygous p.Tyr528His variant segregated completely with late-onset HI in which hearing deteriorated first at high frequencies and progressed to mid and low frequencies later in life. We report the first mutation in the WFS1 gene causing late-onset HI with audiogram configurations typical for ARHI. Monogenic forms of ARHI are rare and our results add WFS1 to the short list of such genes.

Characteristics of audiogram configuration in multiple-system atrophy C and cortical cerebellar atrophy

CONCLUSION

The prevalence of low-tone hearing loss (LTHL) is significantly high in spinocerebellar degeneration (SCD) with cerebellar predominance, including multiple-system atrophy C (MSA-C) and cortical cerebellar atrophy (CCA).

OBJECTIVE

This study aimed to test the hypothesis that SCD with cerebellar predominance, MSA-C and CCA may cause auditory symptoms.

METHODS

The shape and threshold of pure-tone audiograms were evaluated for MSA-C (n = 47; mean (± SD) age, 61.6 ± 8.9 years), CCA (n = 16; 62.8 ± 9.5 years), and age-matched controls (n = 169; 62.5 ± 10.7 years). To differentiate specific hearing loss for MSA-C and CCA from presbycusis, the shape of audiograms was examined based on previously established audiological criteria.

RESULTS

When audiogram shape was defined according to audiological criteria, the odds ratio for LTHL in SCD compared to controls was 2.492 (95% confidence interval (CI) = 1.208-5.139; p < 0.05, Pearson's Chi-square test) in MSA-C and 2.194 (95% CI = 0.709-6.795) in CCA. When the selection of audiogram shape according to these criteria was verified by three certified audiologists, odds ratios for LTHL in MSA-C and CCA were 3.243 (95% CI = 1.320-7.969) and 3.692 (95% CI = 1.052-12.957), respectively, significantly higher than in controls.

Over-the-Counter Hearing Aids: A Lost Decade for Change

Background. Hearing aids sold directly to consumers in retail stores or through the internet, without individual prescription by audiological professionals, are termed over-the-counter (OTC) devices. This study aimed to determine whether there was any change in the electroacoustic characteristics of OTC devices compared to research carried out a decade earlier. The previous results indicated that most OTC devices were low-frequency-emphasis devices and were unsuitable for elderly people with presbycusis, who were likely to be the major consumers of these products. Methods. Ten OTC devices were selected and their electroacoustic performance was measured. Appropriate clients for the OTC devices were derived, using four linear prescription formulae, and OTC suitability for elderly persons with presbycusis was investigated. Results. OTC electroacoustic characteristics were similar to those in the earlier study. Most OTC devices were not acoustically appropriate for potential consumers with presbycusis. Although several of the devices could match prescriptive targets for individuals with presbycusis, their poor electroacoustic performance—including ineffective volume control function, high equivalent input noise, and irregular frequency response—may override their potential benefit. Conclusion. The low-cost OTC devices were generally not suitable for the main consumers of these products, and there has been little improvement in the appropriateness of these devices over the past decade.

A review of hyperacusis and future directions: part I. Definitions and manifestations

PURPOSE

Hyperacusis can be extremely debilitating, and at present, there is no cure. We provide an overview of the field, and possible related areas, in the hope of facilitating future research.

METHOD

We review and reference literature on hyperacusis and related areas. We have divided the review into 2 articles. In Part I, we discuss definitions, epidemiology, different etiologies and subgroups, and how hyperacusis affects people. In Part II, we review measurements, models, mechanisms, and treatments, and we finish with some suggestions for further research.

RESULTS

Hyperacusis encompasses a wide range of reactions to sound, which can be grouped into the categories of excessive loudness, annoyance, fear, and pain. Many different causes have been proposed, and it will be important to appreciate and quantify different subgroups. Reasonable approaches to assessing the different forms of hyperacusis are emerging, including psychoacoustical measures, questionnaires, and brain imaging.

CONCLUSIONS

Hyperacusis can make life difficult for many, forcing sufferers to dramatically alter their work and social habits. We believe this is an opportune time to explore approaches to better understand and treat hyperacusis.

Childhood hearing impairment in northern Finland, etiology and additional disabilities

OBJECTIVES

The purpose of this study was to determine the prevalence and etiology of hearing impairment (HI) in Finnish children and to evaluate the frequency and type of additional disabilities among children with HI.

METHODS

Subjects consisted of 214 children with mild to profound HI ascertained until the age of 10 years. They belonged to the birth cohort spanning the years 1993-2002 in northern Finland. The clinical data were collected from the electronic patient records of the Oulu University Hospital. Age at ascertainment, degree and type of HI and audiogram configuration were determined. Risk factors and etiology of HI and co-existing disabilities were recorded.

RESULTS

The prevalence of childhood HI was 2.3/1000 live births (95% CI; 2.0, 2.7). The etiology of HI was genetic in 47.2%, acquired in 16.4% and unknown in 36.4% children. Among the 214 children with HI, 101 (47.2%) had other minor or major disabilities. The frequency of additional disabilities did not differ between children with mild HI and those with moderate or severe HI (p=0.78). Additional disabilities were more common (65.7%) in children with acquired HI than in children with genetic or unknown HI (43.6%) (p=0.035).

CONCLUSION

The prevalence of childhood HI has remained unchanged in northern Finland as compared to previous studies. Genetic causes were the most common (47%) etiology of childhood HI. Among acquired causes of HI, perinatal risk factors were more common than previously. The frequency of additional disabilities was similar among children with different degrees of HI. Because almost 40% of children had one or more additional disabilities affecting development or learning, it is important to take them into consideration in rehabilitation.

Reference hearing thresholds in an extended frequency range as a function of age

The ISO 7029 (2000) standard defines normative hearing thresholds H (dB hearing level) as a function of age Y (years), given by H = α(Y - 18)(2), up to 8 kHz. The purpose of this study was to determine reference thresholds above 8 kHz. Hearing thresholds were examined using pure-tone audiometry over the extended frequency range 0.125-16 kHz, and the acquired values were used to specify the optimal approximation of the dependence of hearing thresholds on age. A sample of 411 otologically normal men and women 16-70 years of age was measured in both ears using a high-frequency audiometer and Sennheiser HDA 200 headphones. The coefficients of quadratic, linear, polynomial and power-law approximations were calculated using the least-squares fitting procedure. The approximation combining the square function H = α(Y - 18)(2) with a power-law function H = β(Y - 18)(1.5), both gender-independent, was found to be the most appropriate. Coefficient α was determined at frequencies of 9 kHz (α = 0.021), 10 kHz (α = 0.024), 11.2 kHz (α = 0.029), and coefficient β at frequencies of 12.5 kHz (β = 0.24), 14 kHz (β = 0.32), 16 kHz (β = 0.36). The results could be used to determine age-dependent normal hearing thresholds in an extended frequency range and to normalize hearing thresholds when comparing participants differing in age.

Prevalence & characteristics of severe and profound hearing loss in adults in a UK National Health Service clinic

OBJECTIVE

To estimate the prevalence of severe and profound hearing loss in a clinical population and to report the audiological and hearing-aid characteristics for this group, as well as outcome measures from use of hearing aids.

DESIGN

A retrospective observational study initially, followed by a postal Glasgow health status inventory (GHSI) to establish the patients functional outcomes.

STUDY SAMPLE

A clinical database of 32 781 cases was interrogated from which 2199 cases of severe /profound hearing loss were identified. From these, an adult sample stratified in terms of age and gender of n = 302 was contacted.

RESULTS

An estimated 6.7% of the local clinical population and 0.7% of the general population were found to have hearing > 70 dB averaged over 0.5, 1, and 2 kHz. Most patients were fitted with bilateral hearing aids, using a non-linear prescription, and as a group they reported a high level of social support.

CONCLUSIONS

This study has estimated the prevalence of severe and profound hearing loss as 6.7% of the clinical population, and 0.7% of the general population. This is consistent with previous work, although it probably underestimates the prevalence. Further work is indicated to strengthen the estimate.