Hearing Loss, Hearing Aid Use, and Risk of Dementia in Older Adults.

Importance: Hearing loss has been suggested as a risk factor for dementia, but there is still a need for high-quality research to better understand the association between these 2 conditions and the underlying causal mechanisms and treatment benefits using larger cohorts and detailed data. Objective: To investigate the association between hearing loss and incident dementia, as well as how hearing aid use contributes to this association. Design, Setting, and Participants: This population-based cohort study was conducted in Southern Denmark between January 2003 and December 2017 and included all residents 50 years and older. We excluded all persons with dementia before baseline as well as those who did not live in the region 5 years before baseline, with incomplete address history, or who had missing covariate information. Exposures: Individual hearing status based on the Hearing Examinations in Southern Denmark database, which contains data on all pure-tone audiometry examinations performed at public hearing rehabilitation clinics in Southern Denmark. Main Outcomes and Measures: Incident cases of dementia and Alzheimer disease as identified from national registries. Results: The study population comprised 573 088 persons (298 006 women [52%]; mean [SD] age, 60.8 [11.3] years) with 23 023 cases of dementia and mean (SD) follow-up of 8.6 (4.3) years. Having a hearing loss was associated with an increased risk of dementia, with an adjusted hazard ratio (HR) of 1.07 (95% CI, 1.04-1.11) compared with having no hearing loss. Severe hearing loss in the better and worse ear was associated with a higher dementia risk, with an HR of 1.20 (95% CI, 1.09-1.32) and 1.13 (95% CI, 1.06-1.20), respectively, compared with having no hearing loss in the corresponding ear. Compared with people without hearing loss, the risk of dementia was higher among people with hearing loss who were not using hearing aids than those who had hearing loss and were using hearing aids, with HRs of 1.20 (95% CI, 1.13-1.27) and 1.06 (95% CI, 1.01-1.10), respectively. Conclusions and Relevance: The results of this cohort study suggest that hearing loss was associated with increased dementia risk, especially among people not using hearing aids, suggesting that hearing aids might prevent or delay the onset and progression of dementia. The risk estimates were lower than in previous studies, highlighting the need for more high-quality longitudinal studies.

AMTASTM and user-operated smartphone research application audiometry-An evaluation study.

OBJECTIVE: To evaluate two user-operated audiometry methods, the AMTASTM PC-based audiometry and a low-cost smartphone audiometry research application (R-App). DESIGN: A repeated-measures within-subject study design was used to compare both user-operated methods to traditional manual audiometry and to evaluate test-retest reliability of each method. STUDY SAMPLE: 58 subjects were recruited in the study of which 83 ears had normal hearing thresholds and 33 ears had hearing loss (pure-tone average > 25 dB HL). Average age of participants was 44.8 years, with an age range of 11-85. RESULTS: Standard deviation of absolute differences ranged between 3.9-6.9 dB on AMTASTM and 4.5-6.8 dB on the R-App. The highest variability was found at the 8000 Hz frequency (R-App and AMTASTM test) and 3000 Hz frequency (AMTASTM retest). Evaluation of test-retest reliability of AMTASTM and R-App showed SD of absolute differences ranging between 3.5-5.8 dB and 3.1-5.0 dB, respectively. The mean threshold difference between test and retest was within ±1.5 dB on AMTASTM and ±1 dB on the R-App. CONCLUSION: Accuracy of AMTASTM and the R-App was within acceptable limits for audiometry and comparable to traditional manual audiometry on all tested frequencies (250-8000 Hz). Evaluation of test-retest reliability showed acceptable variation on both AMTASTM and R-App. Both user-operated methods could be reliably performed in a quiet non-soundproofed environment.

Eye-Tracking on Touch Screen - Evaluating User Interaction.

This paper suggests a setup for using remote eye-tracking on a touchscreen tablet to evaluate user interaction for older adults interacting with a user-driven hearing test. By using video recordings to support the eye-tracking data, it was possible to evaluate quantitative usability metrics that could be compared to other research findings. The video recordings revealed useful information to distinguish between reasons for gaps in data and missing data and to inform future similar studies of human-computer interaction on a touch screen. Using only portable equipment allows researchers to move to the location of the user and investigate the user interaction of devices in real-world scenarios.

Comparison of hearing aid fitting effectiveness with audiograms from either user-operated or traditional audiometry in a clinical setting: a study protocol for a blinded non-inferiority randomised controlled trial.

INTRODUCTION: There is a worldwide need to enhance the capacity of audiometry testing. The objective of this study is to compare the User-operated Audiometry (UAud) system with traditional audiometry in a clinical setting, by investigating if hearing aid effectiveness based on UAud is non-inferior to hearing aid effectiveness based on traditional audiometry, and whether thresholds obtained with the user-operated version of the Audible Contrast Threshold (ACT) test correlates to traditional measures of speech intelligibility. METHODS AND ANALYSIS: The design will be a blinded non-inferiority randomised controlled trial. 250 adults referred for hearing aid treatment will be enrolled in the study. Study participants will be tested using both traditional audiometry as well as the UAud system and they will answer the questionnaire Speech, Spatial and Qualities of Hearing Scale (SSQ12) at baseline. Participants will be randomly divided to receive hearing aids fitted based on either UAud or traditional audiometry. Three months after participants have started using their hearing aids, they will undergo a hearing in noise test with hearing aids to measure their speech-in-noise performance and answer the following questionnaires: SSQ12, the Abbreviated Profile of Hearing Aid Benefit and the International Outcome Inventory for Hearing Aids. The primary outcome is a comparison of the change in SSQ12 scores from baseline to follow-up between the two groups. Participants will undergo the user-operated ACT test of spectro-temporal modulation sensitivity as part of the UAud system. The ACT results will be compared with measures of speech intelligibility from the traditional audiometry session and follow-up measurements. ETHICS AND DISSEMINATION: The project was evaluated by the Research Ethics Committee of Southern Denmark and judged not to need approval. The findings will be submitted to an international peer-reviewed journal and presented at national and international conferences. TRIAL REGISTRATION NUMBER: NCT05043207.

Ambient Noise in Candidate Rooms for User-Operated Audiometry.

Hearing loss is a widespread problem while treatment is not always accessible, mainly because of the limited availability of hearing care professionals and clinics. In this work, part of the User-Operated Audiometry project, we investigate the acoustic environment of inexpensive non-sound-treated rooms that could be used for unsupervised audiometric testing. Measurements of 10 min of ambient noise were taken from 20 non-sound-treated rooms in libraries and private and public clinics, nine of which were measured twice. Ambient noise was compared against two traditional audiometric sound-treated rooms and Maximum Permissible Ambient noise levels by ISO 8231-1, while factoring for the attenuation by the DD450 circumaural headphones provided. In most non-sound-treated rooms, MPAs were violated only by transient sounds, while the floor-noise level was below MPAs. Non-sound-treated rooms' ambient noise levels presented with much larger fluctuations compared to sound-treated rooms. Almost all violations occurred at low to mid-low frequencies. Our results suggest that large-scale implementation of user-operated audiometry outside traditional audiometric rooms is possible, at least under some realizable conditions. Circumaural headphones' attenuation is probably a necessary condition for all cases. Depending on the room, an online system making decisions based on ambient noise might also be included in combination with active attenuation.

Transportation Noise and Risk of Tinnitus: A Nationwide Cohort Study from Denmark.

BACKGROUND: There is a growing body of evidence linking residential exposure to transportation noise with several nonauditory health outcomes. However, auditory outcomes, such as tinnitus, are virtually unexplored. OBJECTIVES: We aimed to investigate the association between residential transportation noise and risk of incident tinnitus. METHODS: We conducted a nationwide cohort study including all residents in Denmark age ≥30y, of whom 40,692 were diagnosed with tinnitus. We modeled road traffic and railway noise at the most (Ldenmax) and least (Ldenmin) exposed façades of all Danish addresses from 1990 until 2017. For all participants, we calculated 1-, 5-, and 10-y time-weighted mean noise exposure and retrieved detailed information on individual- and area-level socioeconomic covariates. We conducted analyses using Cox proportional hazards models. RESULTS: We found positive associations between exposure to road traffic noise and risk of tinnitus, with hazard ratios of 1.06 [95% confidence interval (CI): 1.04, 1.08] and 1.02 (95% CI: 1.01, 1.03) per 10-dB increase in 10-y Ldenmin and Ldenmax, respectively. Highest risk estimates were found for women, people without a hearing loss, people with high education and income, and people who had never been in a blue-collar job. The association with road Ldenmin followed a positive, monotonic exposure-response relationship. We found no association between railway noise and tinnitus. DISCUSSION: To our knowledge, this is the first study to show that residential exposure to road traffic noise may increase risk of tinnitus, suggesting noise may negatively affect the auditory system. If confirmed, this finding adds to the growing evidence of road traffic noise as a harmful pollutant with a substantial health burden. https://doi.org/10.1289/EHP11248.

User-operated audiometry - an evaluation of expert vs. non-expert headphone placement.

OBJECTIVE: User-operated audiometry faces multiple barriers. One of these is the concern of audiologists that patients (non-experts) placing headphones by themselves results in invalid hearing thresholds due to greater placement variability. DESIGN: Comparative study. Participants took the AMTAS pure-tone air-conduction audiometry under two different conditions, expert and non-expert circumaural headphone placement for five frequencies within the range 250-8000 Hz. Questionnaires were also used to gain insight into the usability of the user-operated audiometry system - as well as the participants' perceived handling of the audiometry headphones. STUDY SAMPLE: Thirty participants (mean age 67.5 years). RESULTS: No statistically significant mean differences in hearing thresholds between the expert and non-expert conditions were found. The mean system usability scale score was 84.5. Handling the headphones was also rated as being easy (30%) or very easy (60%) by most non-experts. CONCLUSION: The conclusion of the study is that non-experts can be trusted to properly equip a pair of circumaural audiometry headphones for the correct conduction of pure-tone audiometry with only a few digital instructions.

User-Operated Audiometry Project (UAud) - Introducing an Automated User-Operated System for Audiometric Testing Into Everyday Clinic Practice.

Hearing loss is the third leading cause of years lived with disability. It is estimated that 430 million people worldwide are affected, and the number of cases is expected to increase in the future. There is therefore increased pressure on hearing health systems around the world to improve efficiency and reduce costs to ensure increased access to quality hearing health care. Here, we describe the User-Operated Audiometry project, the goal of which is to introduce an automated system for user-operated audiometric testing into everyday clinic practice as a means to relieve part of this pressure. The alternative to the existing referral route is presented in which examination is executed via the user-operated system. This route is conceptualized as an interaction between the patient, the system, and the hearing care professional (HCP). Technological requirements of the system and challenges that are related to the interaction between patients, the user-operated system, and the HCPs within the specific medical setting are discussed. Lastly, a strategy for the development and implementation of user-operated audiometry is presented, which includes initial investigations, a validation study, and implementation in a real-life clinical situation.

Residential exposure to transportation noise in Denmark and incidence of dementia: national cohort study.

OBJECTIVE: To investigate the association between long term residential exposure to road traffic and railway noise and risk of incident dementia. DESIGN: Nationwide prospective register based cohort study. SETTING: Denmark. PARTICIPANTS: 1 938 994 adults aged ≥60 years living in Denmark between 1 January 2004 and 31 December 2017. MAIN OUTCOME MEASURES: Incident cases of all cause dementia and dementia subtypes (Alzheimer's disease, vascular dementia, and Parkinson's disease related dementia), identified from national hospital and prescription registries. RESULTS: The study population included 103 500 participants with incident dementia, and of those, 31 219 received a diagnosis of Alzheimer's disease, 8664 of vascular dementia, and 2192 of Parkinson's disease related dementia. Using Cox regression models, 10 year mean exposure to road traffic and railway noise at the most (Ldenmax) and least (Ldenmin) exposed façades of buildings were associated with a higher risk of all cause dementia. These associations showed a general pattern of higher hazard ratios with higher noise exposure, but with a levelling off or even small declines in risk at higher noise levels. In subtype analyses, both road traffic noise and railway noise were associated with a higher risk of Alzheimer's disease, with hazard ratios of 1.16 (95% confidence interval 1.11 to 1.22) for road Ldenmax ≥65 dB compared with <45 dB, 1.27 (1.22 to 1.34) for road Ldenmin ≥55 dB compared with <40 dB, 1.16 (1.10 to 1.23) for railway Ldenmax ≥60 dB compared with <40 dB, and 1.24 (1.17 to 1.30) for railway Ldenmin ≥50 dB compared with <40 dB. Road traffic, but not railway, noise was associated with an increased risk of vascular dementia. Results indicated associations between road traffic Ldenmin and Parkinson's disease related dementia. CONCLUSIONS: This nationwide cohort study found transportation noise to be associated with a higher risk of all cause dementia and dementia subtypes, especially Alzheimer's disease.

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 European Perspective on Auditory Processing Disorder-Current Knowledge and Future Research Focus.

Current notions of "hearing impairment," as reflected in clinical audiological practice, do not acknowledge the needs of individuals who have normal hearing pure tone sensitivity but who experience auditory processing difficulties in everyday life that are indexed by reduced performance in other more sophisticated audiometric tests such as speech audiometry in noise or complex non-speech sound perception. This disorder, defined as "Auditory Processing Disorder" (APD) or "Central Auditory Processing Disorder" is classified in the current tenth version of the International Classification of diseases as H93.25 and in the forthcoming beta eleventh version. APDs may have detrimental effects on the affected individual, with low esteem, anxiety, and depression, and symptoms may remain into adulthood. These disorders may interfere with learning per se and with communication, social, emotional, and academic-work aspects of life. The objective of the present paper is to define a baseline European APD consensus formulated by experienced clinicians and researchers in this specific field of human auditory science. A secondary aim is to identify issues that future research needs to address in order to further clarify the nature of APD and thus assist in optimum diagnosis and evidence-based management. This European consensus presents the main symptoms, conditions, and specific medical history elements that should lead to auditory processing evaluation. Consensus on definition of the disorder, optimum diagnostic pathway, and appropriate management are highlighted alongside a perspective on future research focus.

Reproducibility of Dual-Microphone Voice Range Profile Equipment.

Purpose: The aim of this study was to add further knowledge about the usefulness of the Voice Range Profile (VRP) assessment in clinical settings and research by analyzing VRP dual-microphone equipment precision, reliability, and room effect. Method: Test-retest studies were conducted in an anechoic chamber and an office: (a) comparing sound pressure levels (SPLs) from a dual-microphone VRP device, the Voice Profiler, when given the same input repeatedly (test-retest reliability); (b) comparing SPLs from 3 devices when given the same input repeatedly (intervariation); and (c) assessing the room effect. Results: (a) The mean standard deviation across 17 measurement points was 0.7 dB for 1 device. (b) One device was less precise than the other 2 devices. All devices presented high SPLs at low frequencies compared with the reference. (c) Mean SPLs were almost equal in the anechoic chamber and the office. Conclusions: The high test-retest reliability of the dual-microphone VRP equipment, especially in general office surroundings, is a positive finding. Attention must be paid to specific factors such as using the same device when comparing the same voice before and after treatment, caution in headset placement, and manual recalibrations when automatic recalibration occurs. We suggest recalibrations verified with a reference source at regular intervals.

Implementation and evaluation of a Danish test battery for auditory processing disorder in children.

OBJECTIVE: This study presents a Danish test battery for auditory processing disorder (APD). The tests were evaluated as to normative cut-off values (pass-fail criteria) and their test-retest reliability. DESIGN: The battery consists of four behavioural tests: the filtered words (FW) test, the dichotic digits (DD) test, the gap detection (GD) test and the binaural masking level difference (BMLD) test. The tests were evaluated through listening experiments on children with no known history of auditory problems. STUDY SAMPLE: The normative cut-off values were obtained from 158 children (75 boys and 83 girls, aged 6-16 years), whereas the test-retest reliability was obtained from 20 children (10 boys and 10 girls, aged 6-11 years). RESULTS: For each of the four tests one to four different cut-off values were determined depending on whether the scores from the two ears and the different age groups could be pooled. For each of the four tests the test-retest reliability was found to be satisfactory. The test-retest reliability was highest for the FW and the DD test. CONCLUSIONS: A Danish APD test battery is now available for clinical use with normative data.

Simulated Critical Differences for Speech Reception Thresholds.

Purpose: Critical differences state by how much 2 test results have to differ in order to be significantly different. Critical differences for discrimination scores have been available for several decades, but they do not exist for speech reception thresholds (SRTs). This study presents and discusses how critical differences for SRTs can be estimated by Monte Carlo simulations. As an application of this method, critical differences are proposed for a 5-word sentences test (a matrix test) using 2 widely implemented adaptive test procedures. Method: For each procedure, simulations were performed for different parameters: the number of test sentences, the j factor, the distribution of the subjects' true SRTs, and the slope of the discrimination function. For 1 procedure and 1 parameter setting, simulation data are compared with results found by listening tests (experimental data). Results: The critical differences were found to depend on the parameters tested, including interactive effects. The critical differences found by simulation agree with data found experimentally. Conclusions: As the critical differences for SRTs rely on multiple parameters, they must be determined for each parameter setting individually. However, with knowledge of the test setup, rules of thumb can be derived.

Speech perception in medico-legal assessment of hearing disabilities.

OBJECTIVE: Examination of Danish data for medico-legal compensations regarding hearing disabilities. The study purposes are: (1) to investigate whether discrimination scores (DSs) relate to patients' subjective experience of their hearing and communication ability (the latter referring to audio-visual perception), (2) to compare DSs from different discrimination tests (auditory/audio-visual perception and without/with noise), and (3) to relate different handicap measures in the scaling used for compensation purposes in Denmark. DESIGN: Data from a 15 year period (1999-2014) were collected and analysed. STUDY SAMPLE: The data set includes 466 patients, from which 50 were omitted due to suspicion of having exaggerated their hearing disabilities. RESULTS: The DSs relate well to the patients' subjective experience of their speech perception ability. By comparing DSs for different test setups it was found that adding noise entails a relatively more difficult listening condition than removing visual cues. The hearing and communication handicap degrees were found to agree, whereas the measured handicap degrees tended to be higher than the self-assessed handicap degrees. CONCLUSIONS: The DSs can be used to assess patients' hearing and communication abilities. The difference in the obtained handicap degrees emphasizes the importance of collecting self-assessed as well as measured handicap degrees.

A user-operated audiometry method based on the maximum likelihood principle and the two-alternative forced-choice paradigm.

OBJECTIVE: To create a user-operated pure-tone audiometry method based on the method of maximum likelihood (MML) and the two-alternative forced-choice (2AFC) paradigm with high test-retest reliability without the need of an external operator and with minimal influence of subjects' fluctuating response criteria. User-operated audiometry was developed as an alternative to traditional audiometry for research purposes among musicians. DESIGN: Test-retest reliability of the user-operated audiometry system was evaluated and the user-operated audiometry system was compared with traditional audiometry. STUDY SAMPLE: Test-retest reliability of user-operated 2AFC audiometry was tested with 38 naïve listeners. User-operated 2AFC audiometry was compared to traditional audiometry in 41 subjects. RESULTS: The repeatability of user-operated 2AFC audiometry was comparable to traditional audiometry with standard deviation of differences from 3.9 dB to 5.2 dB in the frequency range of 250-8000 Hz. User-operated 2AFC audiometry gave thresholds 1-2 dB lower at most frequencies compared to traditional audiometry. CONCLUSIONS: User-operated 2AFC audiometry does not require specific operating skills and the repeatability is acceptable and similar to traditional audiometry. User operated 2AFC audiometry is a reliable alternative to traditional audiometry.

User-operated speech in noise test: implementation and comparison with a traditional test.

OBJECTIVE: The purpose of this study was to implement and evaluate a user-operated speech in noise test. DESIGN: The test is based on the Danish speech material Dantale II, which consists of five words sentences ( Wagener et al, 2003 ). For each word presented the subject selected a response from ten alternative words. Two versions of the test were made: one with and one without the possibility that for each word presented the subject could answer "I do not know" (?-button). Using a listening test the two versions were evaluated against a traditional test, where the subjects orally repeated the words that were perceived. STUDY SAMPLE: Twenty-four normal-hearing subjects. RESULTS: The speech intelligibility as a function of the signal-to-noise ratio can be described by logistic functions in the different user-operated tests and in the traditional test. The logistic parameters obtained from the user-operated test with the ?-button agree with the parameters obtained in a traditional test. The homogeneity of the speech material is uninfluenced when the material is used in a user-operated test. CONCLUSIONS: It is reasonable to use the Dantale II speech material for a user-operated speech in noise test, and the use of the ?-button is favourable.

Sound exposure of symphony orchestra musicians.

BACKGROUND: Assessment of sound exposure by noise dosimetry can be challenging especially when measuring the exposure of classical orchestra musicians where sound originate from many different instruments. A new measurement method of bilateral sound exposure of classical musicians was developed and used to characterize sound exposure of the left and right ear simultaneously in two different symphony orchestras. OBJECTIVES: To measure binaural sound exposure of professional classical musicians and to identify possible exposure risk factors of specific musicians. METHODS: Sound exposure was measured with microphones mounted on the musician's ears and recorded digitally. The recorded sound was analysed and the specific sound exposure of the left and the right ear was determined for the musicians. A total of 114 measurements covering 106 h were recorded in two symphony orchestras. RESULTS: Sound exposure depends significantly on the specific instrument and the repertoire played by the exposed musician. Concerts, group rehearsals and individual practice were all significant contributors to the sound exposure. The highest L(Aeq) of 86 -98 dB was found among the brass players. High string players were exposed from 82 to 98 dBA and their left ear was exposed 4.6 dB more than the right ear. Percussionists were exposed to high sound peaks >115 dBC but less continuous sound exposure was observed in this group. Musicians were exposed up to L(Aeq8h) of 92 dB and a majority of musicians were exposed to sound levels exceeding L(Aeq8h) of 85 dB. CONCLUSIONS: Binaural recording of the individual sound exposure showed that orchestra musicians could be exposed differently to the left and right ear and that they were primarily exposed from their own instruments. Specific repertoires as well as the specific instrument determine the level of exposure.