Hearing Threshold Levels Research Articles

Comparison of Preferred Real-Ear Insertion Gain between Open- and Closed-Canal Fitting Hearing Aids

Purpose: To calculate the real-ear insertion gain (REIG) according to the types of hearing aids, we evaluated the preferred REIGs of Korean hearing-impaired listeners and psychoacoustic differences between open-canal fitting (OF) and closed-canal fitting (CF).Methods: The subjects with sensorineural hearing loss were divided into OF group (4 monaural fittings, 15 binaural fittings with 34 ears), and CF group (8 monaural fittings, 13 binaural fittings with 34 ears). There were no statistical differences in hearing threshold level (HTL) at each octave frequencies, word recognition score (WRS) and Korean Adaptation of the International Outcome Inventory for Hearing Aids (K-IOI-HA) between the two groups. When there was no need for further electroacoustic adjustment of the hearing aid, sharpness and occlusion of amplified sound, clarity of sentence, and loudness of noise were evaluated based on the everyday experience. And REIGs with international speech test signal and WRS in sound-treated room were measured.Results: Preferred REIG for HTL was low for OF compared to CF in 0.5 kHz and 0.75 kHz at input SPL of 55 dB, 0.5 kHz at 60 dB SPL, 0.25 kHz and 0.5 kHz at 80 dB SPL. However, there were no differences in aided WRS and psychoacoustics between the two groups.Conclusion: In this study, the preferred REIG of OF and CF groups showed a difference under 0.75 kHz although there were no psychoacoustic differences between the two groups. Therefore, the results of this study should be considered when formulating Korean-type hearing aid fitting formula.

Analysis of correlation between window duration for kurtosis computation and accuracy of noise-induced hearing loss prediction.

Kurtosis is considered an important metric for evaluating noise-induced hearing loss (NIHL). However, how to select window duration to calculate kurtosis remains unsolved. In this study, two algorithms were designed to investigate the correlation between window duration for kurtosis computation and the accuracy of NIHL prediction using a Chinese industrial database. Pure-tone hearing threshold levels (HTLs) and full-shift noise were recorded from each subject. In the statistical comparison, subjects were divided into high- and low-kurtosis groups based on kurtosis values computed over different window durations. Mann-Whitney U test was used to compare the difference in group HTLs to find the optimal window duration to best distinguish these two groups. In the support vector machine NIHL prediction model, kurtosis obtained from different window durations was used as a feature of the model for NIHL evaluation. The area under the curve was used to evaluate the performances of models. Fourteen window durations were tested for each algorithm. Results showed that 60 s was an optimal window duration that allows for both efficient computation and high accuracy for NIHL evaluation at test frequencies of 3, 4 and 6 kHz, and the geometric mean of kurtosis sequence was the best metric in NIHL evaluation.

Transient otoacoustic emissions and audiogram fine structure in the extended high-frequency region

Objective Previous studies at conventional audiometric frequencies found associations between the ripple depth seen in audiogram fine structure (AFS) and amplitudes of both transient evoked otoacoustic emissions (TEOAEs) and overall hearing threshold levels (HTLs). These associations are explained by the cochlear mechanical theory of multiple coherent reflections of the travelling wave apically by reflections sites on the basilar membrane and basally by the stapes. Design The aim was to investigate whether a similar relationship is seen in the extended high-frequency (EHF) range from 8–16 kHz. Measurements from 8–16 kHz were obtained in normal-hearing subjects comprising EHF HTLs, EHF TEOAEs using a double evoked paradigm, and Bekesy audiometry to assess AFS ripple depth and spectral periodicity. Study Sample Twenty eight normal-hearing subjects participated. Results Results showed no significant correlation between AFS ripple depth and either frequency-averaged EHF HTLs or EHF TEOAE amplitudes. The amplitude of AFS ripple depth was also lower than that seen in the conventional frequency region and spectral periodicity in the ripple more difficult to discern. Conclusion The results suggest a weaker interference pattern between forward and reverse cochlear travelling waves in the most basal region compared to more apical regions, or a difference in cochlear mechanical properties.

The Effect of Exposure to Noise during Military Service on the Subsequent Progression of Hearing Loss.

This paper reviews and re-analyses data from published studies on the effects of noise exposure on the progression of hearing loss once noise exposure has ceased, focusing particularly on noise exposure during military service. The data are consistent with the idea that such exposure accelerates the progression of hearing loss at frequencies where the hearing loss is absent or mild at the end of military service (hearing threshold levels (HTLs) up to approximately 50 dB HL), but has no effect on or slows the progression of hearing loss at frequencies where the hearing loss exceeds approximately 50 dB. Acceleration appears to occur over a wide frequency range, including 1 kHz. However, each of the studies reviewed has limitations. There is a need for further longitudinal studies of changes in HTLs over a wide range of frequencies and including individuals with a range of HTLs and ages at the end of military service. Longitudinal studies are also needed to establish whether the progression of hearing loss following the end of exposure to high-level sounds depends on the type of noise exposure (steady broadband factory noises versus impulsive sounds).

Hearing threshold levels of Australian coal mine workers: a retrospective cross-sectional study of 64196 audiograms

Objective This study examined the hearing threshold levels (HTL) of workers commencing employment in Australian coal mines in the State of New South Wales (NSW). The aim was to establish if some degree of hearing loss was identifiable in the mandatory pre-employment audiograms of workers. Design This was an observational, retrospective, repeated cross-sectional study. Study sample De-identified audiometric records of 64196 employees entering NSW coal mining in three representative five-year periods between 1991–2015 were utilised. Results Although HTLs were lower (better) in more recent years, the results showed clinically significant hearing loss (≥25dBHL) for older workers, 45–60 years. Pure tone average (PTA) hearing losses were greater at the higher frequencies associated with excessive noise exposure (3–6 kHz), than at the speech frequencies (0.5–4 kHz). Hearing loss in the left ears were higher compared to the right ears, with higher prevalence of audiometric notches in males. Conclusion Almost a fifth (14.8–20.1%) of male workers commencing work in NSW coal mines presented with an audiometric notch at 4 kHz. Further research is required to determine if these notches represent true NIHL, and how the residual hearing of workers may be conserved.

An assessment of noise exposure and hearing health status among auto body workers in Kermanshah, Iran.

BACKGROUND:Unwanted sound is recognized as the most extensive source of contaminant in the workplace. Exposure to intense, continuous, and higher than 85 dB level noise can lead to noise-induced hearing loss. The aim of the present study was to determine the level of noise exposure and its impact on hearing health among auto body workers.MATERIALS AND METHODS:This descriptive-analytic study was conducted in 2020 to investigate the hearing health status of workers in auto body workshops. Sixty-one participants were randomly selected for audiometric testing. The equivalent sound level (Leq) of the workers was measured using a Casella CEL-320 noise dosimeter. Audiometric testing was performed using an AC40 audiometer. The mean hearing threshold levels (HTLs) of both ears were calculated for different frequencies. The results obtained were analyzed using SPSS v21.0 at a significance level of 95%.RESULTS:The participants had an average age of 35.5 ± 11.8 years and an average work experience of 16.5 ± 9.8 years. The mean Leq was 92.3 ± 4.7 dB. The mean HTLs for the right ear and left ear were 20, 15, 17.6, 19.2 dB, respectively with the right ear suffering more loss. A significant relationship was found between hearing loss in both ears (P < 0.001). The highest prevalence of hearing loss in both ears was observed at a frequency of 4 kHz. About 73.8% of the subjects had a normal HTL, 23.3% had mild hearing loss, and 3.3% had severe hearing loss. With increasing work experience, HTLs also increased significantly, particularly at 2–8 kHz.CONCLUSIONS:Chronic exposure to noise pollution threatens hearing health. Therefore, it is necessary to raise the level of awareness among workers in order to enable better hearing health protection and also to promote the use of hearing protection devices.

Outcomes of Cochlear Implantation in Post-lingually Deaf Patients.

Cochlear implantation has been mentioned as the most effective therapeutic intervention in deaf patients and especially those with post-lingual deafness. We aimed to assess hearing improvement of post-lingually deaf patients after cochlear implantation. in this cross-sectional study all the post-lingually deaf patients who had undergone cochlear implantation (CI) surgery between December 2010 and February 2016 were assessed. Patients were recalled and after explaining the study process and signing an informed consent form, an audiometry was done by a single audiologist. In addition, demographic information, cause of hearing loss, age of onset, history of hearing aid use and surgical complications were recorded in a pre-designed checklist. Twenty-nine male and 21 female with a mean age of 22.52±19.45 years underwent analysis. Most of patients (80%) had progressed condition since childhood. Sudden sensorineural hearing loss (SSNHL) was the most prevalent (10%) known etiology of deafness followed by meningitis (6%), Trauma (2%) and ototoxic drugs (2%) in the remaining 20% of the patients. Patients had the highest mean (37.1±12.61 dB) in 4000 Hz frequency and the lowest mean of hearing threshold level (32.6±8.37 dB) was for 1000 Hz frequency. Mean hearing threshold level was significantly lower in patients with lower ages of cochlear implantation (p=0.435). Patients with higher ages of deafness onset showed lower degree of hearing improvement (p=0.462). The results of our study suggest that cochlear implantation significantly improves hearing function of post-lingual patients and can be considered as a certain cure for these patients in Iran.

Hearing-impaired Children and Adults in Need of Cochlear Implant- A Hospital Based Cross-sectional Study

Introduction: Hearing is essential to learn language and speech and to develop cognitive skills. According to World Health Organisation (WHO), world-wide approximately 350 million people have hearing disorder. The performance of some moderately severe hearing-impaired adults and children using hearing aids is poorer than that of even profoundly hearing-impaired individuals using cochlear implants with advanced speech processing strategies. Aim: To find out the appropriate candidates in need of cochlear implantation in Prayagraj district of Uttar Pradesh, India. Materials and Methods: This cross-sectional study was conducted on hearing impaired patients attending Ear Nose Throat (ENT) Out Patient Department (OPD) of tertiary health care center in Prayagraj Uttar Pradesh from August 2011 to July 2012. The study population consisted of 95 patients categorised into four groups (pre-lingual children and adults, post-lingual children and adults) who presented with the chief complaints of impaired hearing and delayed speech. A detailed history, clinical and other relevant systemic examination and investigations were done. Patients were subjected to free field audiometry, pure tone audiometry and Brainstem-Evoked Response Audiometry (BERA) for assessment of hearing threshold level. Patients used hearing aid for six months and after hearing aid use, their hearing threshold and speech discrimination scores were estimated. Patients, whose aided score on open-set sentence test was less than 50%, were selected as candidate for cochlear implants, as they were not significantly benefited by hearing aids. Results: Out of the 95 cases, 48 were found to be suitable for cochlear implantation, which formed 50.5% of the study group. Pre-lingual hearing impaired adults had the highest percentage i.e., 86.7%, fulfilling the criteria for cochlear implantation followed by pre-lingual children, in whom 46.7% fell in this category. A 26.7% of postlingual children and 20% of postlingual adults were found suitable for cochlear implantation. Conclusion: The pre-lingual hearing impaired children and adults are more in need for cochlear implantation than the postlingual hearing-impaired children and adults. Approximately, 134,501 cases were estimated to be, in need of cochlear implantation in Prayagraj district based on the census estimate of 2011.

Immediate Treatment of Sudden Sensorineural Hearing Loss: A Case Study

Immediate Treatment of Sudden Sensorineural Hearing Loss: A Case Study

PORÓWNANIE SŁUCHOWYCH POTENCJAŁÓW KOROWYCH N1P2 I POTENCJAŁU STANU USTALONEGO GENEROWANEGO WĄSKOPASMOWYM BODŹCEM TYPU CHIRP W ROZPOZNANIU PROGU SŁYSZENIA U OSÓB DOROSŁYCH

BackgroundVarious auditory evoked potential techniques have been explored as a means of objectively predicting the behavioral audiogram in groups of subjects who cannot provide reliable or accurate behavioral results. The tone-evoked auditory brainstem response (ABR) cannot differentiate between severe and profound SNHL, whereas the auditory steady state response (ASSR) can provide threshold information in a frequency-specific manner at intensity levels of 120 dBSPL. The cortical auditory evoked potential (N1P2 CAEP) has shown advantages over the ABR and ASSR.ObjectivesTo assess the ability of the N1P2 cortical auditory evoked potential (CAEP) to estimate the hearing threshold level at different frequencies, in normal hearing adults and adults with different degrees of sensorineural hearing loss (SNHL); and to compare it to the auditory steady state response (ASSR).MethodsThis study included 90 subjects (180 ears), grouped into 6 groups according to the degree of hearing obtained by pure tone audiometry (PTA). Hearing threshold was then measured using N1P2 CAEP and ASSR.ResultsN1P2 CAEP and ASSR were highly correlated to PTA at all frequencies. However, N1P2 CAEP predicted behavioral thresholds more accurately than ASSR at all frequencies, especially at 500 and 1000 Hz in the normal hearing group and for all degrees of SNHL. N1P2 CAEP was equally accurate at all frequencies and predicted behavioral thresholds better at more severe degrees of SNHL at 1, 2, and 4 kHz.ConclusionsThe N1P2 CAEP can be reliably used as an objective method for estimating the behavioral hearing threshold, yielding more accurate results than the ASSR, especially at lower frequencies and with more severe degrees of hearing loss. We therefore recommend using the N1P2 CAEP in estimating the behavioral threshold in difficult-to-test adults.

The accuracy of standard audiometric hearing level thresholds in pediatric patients

ObjectivesStandard audiograms provide decibels Hearing Level (dB HL) thresholds, which are referenced to normative values specified in decibels Sound Pressure Level in an acoustic coupler. Due to variability in external ear acoustics, the actual sound levels reaching the eardrum can vary across individuals. The real-ear to coupler difference (RECD) is a frequency-specific measurement of the difference between sound levels measured at the eardrum and in a coupler. Here, we compare the standard audiogram dB HL levels to RECD corrected hearing thresholds (dB RECHL) in children. MethodsChildren who underwent standard audiometric and RECD testing were included. The dB RECHL was established and the differences between dB HL and dB RECHL (threshold error) was calculated. A threshold error >5 dB was considered significant. ResultsA total of 166 children were included (mean age 12 years). Overall, 14% had normal hearing, 52% had conductive hearing loss and 27% had sensorineural hearing loss. Hearing threshold levels were overestimated by the standard audiogram compared to dB RECHL, at all frequencies (250–6000 Hz). In the lower frequencies and at 6000 Hz, 33–59% of patients were overestimated, with a threshold error up to 25 dB. In the mid frequencies, 33% were overestimated with a similar threshold error. ConclusionStandard audiogram thresholds overestimated hearing levels in children which may have clinical implications. This problem can be addressed by correcting thresholds with RECD. More studies are needed to assess the effect of correcting thresholds on hearing outcomes in children.

Assessment of Quwat -e- Sami,ah (Hearing threshold level) in different temperaments

Assessment of Quwat -e- Sami,ah (Hearing threshold level) in different temperaments

The Analysis of Hearing Threshold Level of Noise Exposed Workers in Circulator Loom Unit

Introduction: One of the hazards caused by the process of producing plastic sacks is noise. Noise is unwanted sound judged to be unpleasant, loud or disruptive to hearing. Noise is produced by machines used in the production process. Noise that exceeds the threshold limit value (TLV) at workplace can cause hearing loss. The purpose of this study was to analyze the hearing threshold level of workers who were exposed to noise in circulator loom unit at PT. Kerta Rajasa Raya Sidoarjo. Method: This was an observational study with a cross sectional approach. The population of this study was 47 workers, while the sample was the total population. The independent variable wasnoise, while the dependent variable was the hearing threshold level. Contingency coefficient was used to detemine the strength of correlation between variables. Noise intensity measurement at three points revealed that the value exceeded the time limit value. Result: Most of the workers were &gt; 40 years old (72.3%), had work period of 15-20 years (51.07%) and never consumed ototoxic medication (80.85%). Conclusion: A moderate correlation between the noise intensity and hearing threshold level of right ear. However, the correlation between noise intensity and hearing threshold level of left ear is weak. Keywords: hearing threshold level, noise, work characteristic

Correlation of malondialdehyde and hearing threshold level at frequency 4000 Hz post gunshot exposure

Background: The incidence of acoustic trauma after gunshot exposure in students of the SekolahPolisi Negara (SPN) is quite high. Malondialdehyde (MDA) is a compound that can portray oxidativestress due to free radicals. The correlation between the levels of MDA and the hearing threshold frequencypost gunshot exposure could be used as the base for administering antioxidants to prevent acoustictrauma. Objective: To find out the correlation between the levels of MDA and the hearing thresholdfrequency post gunshot exposure, in East Java SPN students. Method: An observational analytic studywith a retrospective cross sectional approach using secondary data of medical records of the East JavaSPN students batch 2017/2018. The samples were selected by simple random sampling. Result: Out of50 students, the mean of age was 19.62 years. All samples were male with mean 559.17 and standarddeviation (SD) 959.86. The calculation of the 4000 Hz frequency threshold value obtained an averagevalue of 31.52 and SD of 13.4. Hearing loss complaint was found in 1 student (2%). No complaints oftinnitus and vertigo were found. Statistical tests with Pearson correlation between serum MDA levels and4000 Hz frequency threshold values showed a correlation coefficient (r) of 0.74 and p = 0.00 (p&lt;0.05).Conclusion: There was a significant correlation between MDA levels and the hearing threshold at 4000Hz frequency after gunshot exposure in East Java SPN students.Keywords: acoustic trauma, malondialdehyde, hearing threshold level at frequency 4000 HzABSTRAKLatar belakang: Insiden trauma akustik pasca pajanan letusan senjata api pada siswa Sekolah PolisiNegara (SPN) cukup tinggi. Malondialdehid (MDA) merupakan senyawa yang dapat menggambarkanstres oksidatif akibat radikal bebas. Adanya hubungan antara kadar MDA dengan nilai ambang dengarfrekuensi 4000 Hertz (Hz) dapat menjadi dasar pemberian antioksidan untuk pencegahan traumaakustik. Tujuan: Membuktikan hubungan antara kadar MDA dengan nilai ambang dengar frekuensi4000 Hz pasca pajanan letusan senjata api pada siswa SPN Jawa Timur. Metode: Penelitian ini adalahobservasional analitik dengan pendekatan retrospektif cross sectional menggunakan data sekunderberupa rekam medik siswa SPN Jawa Timur angkatan 2017/2018. Sampel dipilih secara simple random sampling. Hasil: Dari 50 siswa, usia rerata adalah 19,62 tahun. Seluruh sampel penelitian adalah laki-laki, rerata=559,17 dan standar deviasi (SD)=959,86. Penghitungan nilai ambang dengar frekuensi 4000 Hz didapatkan hasil nilai rerata=31,52 dan SD=13,4 Keluhan penurunan pendengaran hanya dijumpai pada 1 siswa (2%). Uji statistik dengan korelasi Pearson antara kadar MDA dalam serum dengan nilai ambang dengar frekuensi 4000 Hz didapatkan hasil koefisien korelasi (r) sebesar 0,74 dan p = 0,00 (p&lt;0,05). Kesimpulan: Terdapat hubungan yang signifikan antara kadar MDA dengan nilai ambang dengar frekuensi 4000 Hz pasca pajanan letusan senjata api pada siswa SPN Jawa Timur.Kata kunci: trauma akustik, malondialdehid, nilai ambang dengar frekuensi 4000 Hz

超高齢期（90 歳以上）の聴力と語音明瞭度の関係について

超高齢期（90 歳以上）の聴力と語音明瞭度の関係について

Factors Associated with Depressive Symptoms in the Elderly with Hearing Impairment

Purpose: The purpose of this study was to examine factors associated with depressive symptoms in the elderly with hearing impairment.Methods: We studied 23 hearing-impaired elderly persons aged 60 years or older. The participants underwent audiometric, neuropsychological, and depression assessments. Neuropsychological tests were subsumed in specific cognitive domains (general cognition, semantic memory, processing speed, executive function). The short version of the geriatric depression scale was administered to obtain depressive symptom scores for each subject.Results: First, among audiometric variables, the pure-tone threshold average, sentence-in-noise recognition scores, and hearing handicap scores were significantly correlated with the depressive symptom scores. Second, among neuropsychological variables, the reaction time on the part A of the Korean version of trail making test for the elderly (K-TMT-E), which is reflective of processing speed, was correlated with the depressive symptom scores. Also, the reaction time on the part B of the K-TMT-E, which is reflective of executive function, was correlated with the depressive symptom scores. Lastly, in the stepwise regression analysis, the pure-tone threshold average and the reaction time on the part B of the K-TMT-E were found to be factors significantly associated with depressive symptom scores.Conclusion: Our findings suggest that, for the hearing-impaired elderly, hearing threshold levels and executive function, especially cognitive flexibility are significant factors associated with depression levels.

Cardiovascular Risk and Hearing Threshold Levels on Disc Jockey Workers

Introduction: Noise-induced hearing loss is a major public health problem. Extended exposure to noisy music can cause not only hearing loss, but also biochemical changes in exposed Disc Jockey (DJ) workers. Aim of work: To study some health hazards; mainly biochemical changes and hearing threshold levels among DJ workers compared with a well-matched control group and the prevalence of using protective measures among this occupational group. Materials and methods: A cross-sectional controlled study was conducted at Benha city, Kalyobiya Governorate, Egypt. Data was collected from the beginning of May till the end of September 2017. Sixty-three DJ workers and well-matched seventy-two office workers were subjected to an interview structured questionnaire, clinical examinations including audiometric hearing threshold assessment, biochemical analysis and Framingham coronary heart disease risk score was calculated. Results: The hearing threshold was affected in 59% of DJ workers. Blood pressure, pulse and lipid profile were statistically significantly higher in DJ workers (except HDL was lower). The difference in audiometric measures starts at 3000 at right ear and 4000 at left ear. The only significant predictor for hearing affection was work duration. Conclusion: Noise is one of the disturbing factors for health. In addition to impairing of hearing, noise affects blood pressure, blood glucose and lipid profiles which acts as risk factor for cardio vascular diseases.

Effects of Cardiovascular Health Factors and Personal Listening Behaviors on Hearing Sensitivity in College-Aged students.

This study examined the association between pure tone hearing sensitivity and music listening behaviors among traditional college-aged students and sought to determine factors that mediate hearing sensitivity, including health and fitness levels, gender, and personal listening device (PLD) use. A convenience sample of college students (N = 182; 133 females, 49 males, mean age = 19.8 ± 1.4 year, average PLD use = 1.52 ± 7.1 hours•day-1) completed hearing assessments, music listening behavior questionnaires, and health and fitness tests. Most students listened to music at safe intensity levels (<80 dBA), though 18% had higher hearing levels (≥25 dB HL at one of the measured frequencies). Longer listening duration behavior approached but did not reach a statistical association with compromised hearing sensitivity. Of all variables measured, including cardiovascular health, fitness, and music listening, two variables: total cholesterol: triglycerides (TC:TG) and total cholesterol: high-density lipoproteins (TC:HDL) significantly associated with hearing sensitivity at 2 kHz. The odds hearing loss occurring at 4 kHz was 59% lower in females compared with males. The majority of college students had healthy music listening behavior and fitness, contributing to normal hearing sensitivity in most. In cases where greater hearing threshold levels at one or more frequencies was detected, TC:HDL and TC:TG were statistically related and at 2 kHz, males were more likely to demonstrate higher listening levels compared with females of similar health and fitness level.

Effects of Vibrant Soundbridge on tinnitus accompanied by sensorineural hearing loss.

Tinnitus is a common symptom among patients with hearing loss, and many studies have reported successful tinnitus suppression with hearing devices. Active middle ear implantation of the Vibrant Soundbridge (VSB) is a good alternative to existing hearing devices. This study evaluated the effects of VSB implantation on tinnitus and sought to identify the main audiological factor that affects tinnitus suppression. The study participants were 16 adults who had tinnitus with sensorineural hearing loss, and who underwent VSB implantations. Pure-tone audiometry; word recognition test; tinnitus handicap inventory (THI); and visual analog scale (VAS) assessment of loudness, awareness, and annoyance were performed before and 12 months after surgery. Changes in hearing threshold, word recognition scores (WRS), THI scores, and VAS scores were analyzed. VAS scores for loudness (mean difference: 1.9, 95% CI: 0.6, 3.1), awareness (mean difference: 1.6, 95% CI: 0.4, 2.8), and annoyance (mean difference: 1.7, 95% CI: 0.7, 2.8) showed significant improvements from baseline to 12 months after surgery. In addition, THI scores showed a significant decrease (mean difference: 13.8, 95% CI: 2.9, 24.9). The average hearing threshold level, WRS, and most comfortable level (MCL) also showed significant improvements at 12 months after surgery (mean difference: 17.3, 95% CI: 13.3, 21.3; mean difference: -7.6, 95% CI: -15.1, -0.1; mean difference: 26.3, 95% CI: 22.9, 29.6, respectively). Among the aforementioned factors, changes in MCL were best correlated with those in THI scores (mean difference: 2.55, 95% CI: 0.90, 4.21). A VSB implant is beneficial to subjects with tinnitus accompanied by sensorineural hearing loss. The changes in THI scores best correlated with those in MCL. This improvement may represent a masking effect that contributes to tinnitus suppression in patients with VSB implants.

HEARING IMPAIRMENT, COGNITIVE PERFORMANCE, AND BETA-AMYLOID DEPOSITION IN THE ARIC-PET AMYLOID IMAGING STUDY

Hearing impairment is a risk factor for dementia but the mechanism underlying this association is unknown. We investigated the relationship between hearing and cognitive performance and brain β-amyloid deposition in 252 adults aged 67-88 years (37% black race) without dementia from three U.S. communities. Global cortical standardized uptake value ratios (SUVRs) were calculated from florbetapir-positron emission tomography scans, with elevated SUVR defined as >1.2 (the median value). Air conduction hearing threshold levels for the frequencies of 0.5, 1, 2 and 4 kHz were obtained by pure tone audiometry and averaged for the better-hearing ear to yield a pure tone average (PTA) in decibels hearing level (dB). A composite cognitive score was created from ten neuropsychological tests summarized using latent variable methods. Multivariable-adjusted linear and Poisson regression with robust standard errors were used to estimate the average difference in cognitive scores and prevalence of elevated SUVR, respectively, by hearing impairment status. In analyses adjusted for age, sex, education and APOE ε4 status, hearing was not associated with elevated SUVR [prevalence ratio per 10 db increase (worse hearing) = 0.94 (95% CI: 0.84, 1.04)]. Results did not differ by race. In contrast, each 10 db increase in hearing impairment was associated with 0.08 standard deviation (95% CI: 0.02, 0.15) lower cognitive score, after adjustment for demographic and cardiovascular factors. Poorer hearing is associated with poorer cognitive performance but not with amyloid deposition, suggesting that the mechanism underlying the relationship between hearing and cognition may be independent of Alzheimer’s-related pathologic brain changes.