Prevalence of hearing loss and associated factors in subjects with normal otoscopy: a national cross-sectional study

The Hearing Function and Ambulatory Blood Pressure in Older Adults

OBJECTIVE

To examine the association between hearing function, assessed with pure-tone average (PTA) of air conduction thresholds, and 24-hour ambulatory blood pressure (BP) in older adults.

STUDY DESIGN

Cross-sectional study.

SETTING

A total of 1404 community-dwelling individuals aged ≥65 years from the Seniors-ENRICA cohort were examined.

METHODS

Hearing loss was defined as PTA > 40-AudCal hearing loss decibels (dB-aHL) in the better ear for standard frequency (0.5, 1, and 2 kHz), speech frequency (0.5, 1, 2, and 4 kHz), and high frequency (3, 4, and 8 kHz). Circadian BP patterns were calculated as the percentage decline in systolic BP during the night, and participants were classified as dipper, nondipper, and riser. Ambulatory hypertension was defined as BP ≥ 130/80 mm Hg (24 hour), ≥135/85 (daytime), and ≥120/70 (nighttime) or on antihypertensive treatment. Analyses were performed with linear- and logistic-regression models adjusted for the main confounders.

RESULTS

In multivariable analyses, the PTA was associated with higher nighttime systolic BP [β coefficient per 20 dB-aHL increment standard frequency (95% confidence interval, CI): 2.41 mm Hg (0.87, 3.95); β (95% CI) per 20 dB-aHL increment speech frequency 2.17 mm Hg (0.70, 3.64)]. Among hypertensive patients, hearing loss at standard and high-frequency PTA was associated with the riser BP pattern [odds ratio: 2.01 (95% CI, 1.03-3.93) and 1.45 (1.00-2.09), respectively]; also, hearing loss at standard PTA was linked to uncontrolled nighttime BP [1.81 (1.01-3.24)].

CONCLUSION

PTA was associated with higher nighttime BP, and hearing loss with a riser BP pattern and uncontrolled BP in older hypertensives.

Hearing health and noise exposure in population between 18 to 64 years old in Bogotá, Colombia, 2014-2018

Introduction

Hearing health is a public health concern that affects the quality of life and can be disturbed by noise exposure, generating auditory and extra-auditory symptoms. Objective. To identify the hearing health status in adults living in Bogotá and its association with environmental noise exposure and individual and otological factors.

Objective

To identify the hearing health status in adults living in Bogotá and its association with environmental noise exposure and individual and otological factors.

Materials and methods

We conducted a cross-sectional study using a database with 10,311 records from 2014 to 2018, consigned in a structured survey of noise perception and hearing screening. We performed a descriptive, bivariate, and binary logistic regression analysis.

Results

Of the included participants, 35.4% presented hearing impairment. In the perception component, 13.0 % reported not hearing well; 28.8 % had extra-auditory symptoms, 53.3 % informed otological antecedents and 69.0 % presented discomfort due to extramural noise. In the logistic regression, the variables with the highest association for hearing impairment were living in noisy areas (OR = 1.50) (95% CI: 1.34-1.69), being male (OR = 1.85) (95% CI: 1.64-2.09), increasing age (for each year of life, the risk of hearing impairment increased 6%), and having history of extra-auditory symptoms (OR = 1.86) (95% CI: 1.66-2.08).

Conclusions

Hearing impairment is multi-causal in the studied population. The factors that promote its prevalence are increasing age, being male, smoking, ototoxic medications, living in areas with high noise exposure, and extra-auditory symptoms.

Relationship Between Peripheral and Central Auditory Abilities and Iron Deficiency Anemia in Adolescent Girls

PURPOSE

This study evaluated the peripheral hearing and central auditory processing abilities in Indian adolescent girls with iron deficiency anemia (IDA).

METHOD

The participants consisted of 75 adolescent girls with IDA, 50 adolescent girls without IDA, and 50 adolescent boys without IDA. Participants underwent a test battery to evaluate auditory processing and peripheral hearing assessment. In this study, central auditory processing abilities were assessed using Speech Perception in Noise test in Kannada (SPIN-K) and quick speech perception in noise tests in Kannada, dichotic consonant-vowel test, gap detection threshold (GDT), and auditory digit sequencing and auditory digit span tests.

RESULTS

Results showed that the hearing thresholds at extremely low and high frequencies (250 and 8000 Hz), although within clinically normal limits, were poorer in girls with IDA than in the control groups. Also, girls with IDA performed poorly in SPIN-K of the right ear, GDT, and auditory backward digit span tests.

CONCLUSION

These subtle auditory deficiencies may be attributed to the compromised blood supply to the central auditory nervous system, as observed in the current study.

[Self-reported hearing impairment and occupational exposure to hazardous noise and ototoxic agents: a population-based study]

This study's objective was to estimate the association between self-reported hearing impairment and occupational exposure to hazardous noise and ototoxic agents in Brazilian workers. This was a cross-sectional study with data from the Brazilian National Health Survey (PNS-2013). The dependent variable was self-reported hearing impairment, and three principal exposures were analyzed: noise, industrial dust, and chemical substances. Logistic regression was performed, estimating crude and adjusted odds ratios (OR) with 95% confidence intervals (95%CI). The principal exposure variables were adjusted for each other and by covariables sex, age, workplace, time on the job, and hypertension. 36,442 workers participated in the study. Higher prevalence of hearing impairment was seen in workers exposed to industrial dust (9.9%) (p < 0.001). The older the worker and the longer the time on the job, the higher the prevalence of hearing impairment (p < 0.001). In the adjusted analysis, workers exposed to noise showed 1.65 higher odds of reporting difficulty hearing, when compared to unexposed individuals (p < 0.001). The same was true for workers exposed to industrial dust (OR = 1.36) (p = 0.012). No association was observed between the outcome and exposure to chemical substances (p = 0.120). There was an association between hearing impairment and occupational exposure to noise and industrial dust in Brazilian workers. This emphasizes the importance of strengthening public policies for hearing health and the development of measures for prevention and auditory monitoring in the workplace.

Hearing Status of Low-Income, Middle-Aged and Elderly Women in Northern China: A Population-Based, Cross-Sectional Study

Objective

Hearing impairment (HI) has become one of the most common causes of disability worldwide. To date, few studies have examined the hearing of women in these frequently rural regions. Thus, we explored the HI prevalence and risk factors among low-income, middle-aged, and elderly women in Tianjin, China.

Methods

Between October and November 2013, female residents aged ≥45 years of rural Tianjin, China were recruited into the study. The participants completed questionnaire surveys, physical examinations, and hearing tests. The hearing at frequencies of 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz was used to analyze the hearing characteristics of specific frequency bands, and HI was defined as the better ear pure tone averages (PTA) >25 dB HL.

Results

Among the 1416 participants, the prevalence of HI was 46.0%. Among those aged 45-54-years, most (65.3%) demonstrated normal hearing; in other age groups, slight HI accounted for the largest proportions of individuals. Compared with women who did not drink, the odds ratio (OR) of HI among women who consumed alcohol was 4.2 (95% confidence interval [CI]: 1.844-9.574; P = 0.001). Compared with pre-menopausal women, the OR of HI among postmenopausal women was 1.8 (95% CI: 1.261-2.667; P = 0.001). Further, each 1-year increase in age in women resulted in a 7.1% increase in HI risk (P < 0.001).

Conclusion

The burden of HI among women is heavy in rural northern China, especially among those who experienced menopause. Additionally, the results suggest that to further reduce the risk of developing HI, women in rural areas should stop consuming alcohol. The problem of HI among women in rural areas should be taken seriously; moreover, the measures implemented to prevent HI in high-risk women should be strengthened.

Association between kidney function and hearing impairment among middle-aged and elderly individuals: a cross-sectional population-based study

OBJECTIVE

As age-related diseases, chronic kidney disease and hearing impairment (HI) cause a serious socioeconomic burden. Due to structural similarities, there is a certain connection between kidney function and hearing, but there has been no large-scale epidemiological study in China that further explored this connection. Thus, this study aimed to explore the association between indicator levels of kidney function and hearing impairment among middle-aged and elderly individuals in Tianjin, China.

METHOD

In 2020, 1539 participants aged 45 years or older from Tianjin, China, were recruited into this study. All participants completed questionnaire surveys and underwent physical examinations, laboratory examinations, and hearing tests. The estimated glomerular filtration rate (eGFR) was calculated from serum creatinine (Cre) levels. HI was measured using pure-tone audiometry, and audiologists determined the final diagnoses.

RESULT

The prevalence of HI was 49.97%. With each 1-mL/min/1.73 m² increase in eGFR, the overall odds of HI increased by 1.3%; the risk increased by 2.4% and 1.6% for men and people aged 45-65 years, respectively. In contrast, in women, the odds of HI increased as Cre levels increased. Moreover, with each 1-mL/min/1.73 m² increase in eGFR, the overall odds of a one-degree increase in hearing loss increased by 1.7%; the odds increased by 2.3% and 1.5% for men and people aged 45-65 years, respectively. However, in women and people aged ≥65 years, the odds of a one-grade increase in hearing loss increased by 2.1% and 1.5%, respectively, with each 1-µmol/L increase in Cre. In addition, there were no significant relationships between blood urea nitrogen and hearing loss in multivariate analysis (all P > 0.05).

CONCLUSIONS

These findings suggest that eGFR and serum Cre are effective predictors of hearing loss. Thus, to decrease the burden of HI, hearing should be carefully monitored for people aged ≥45 years with elevated serum Cre and eGFR.

Longitudinal Blood Pressure Patterns from Mid-to-Late Life and Late-life Hearing Loss in the Atherosclerosis Risk in Communities Study

BACKGROUND

Hearing loss is prevalent and associated with adverse functional outcomes in older adults. Prevention thus has far-reaching implications, yet few modifiable risk factors have been identified. Hypertension may contribute to age-related hearing loss, but epidemiologic evidence is mixed. We studied a prospective cohort of 3,343 individuals from the Atherosclerosis Risk in Communities study, aged 44-65 years at baseline with up to 30 years of follow-up.

METHODS

Hearing was assessed in late-life (2016-17) using a better-ear audiometric pure tone average (PTA, 0.5, 1, 2, 4 kHz) and the Quick Speech-in-Noise (QuickSIN) test. Hypertension was defined as systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg or antihypertensive medication use. Mid-life hypertension was defined by hypertension at two consecutive visits between 1987-89 and 1996-98. Late-life hypertension was defined in 2016-17. Late-life low blood pressure was defined as systolic blood pressure <90 mmHg or diastolic blood pressure <60 mmHg, irrespective of antihypertensive medication use. Associations between blood pressure patterns from mid-to-late-life and hearing outcomes were assessed using multivariable-adjusted linear regression.

RESULTS

Compared to persistent normotension, persistent hypertension from mid-to-late-life was associated with worse central auditory processing (difference in QuickSIN score = -0.66 points, 95% CI: -1.14, -0.17) but not with audiometric hearing.

CONCLUSIONS

Participants with persistent hypertension had poorer late-life central auditory processing. These findings suggest that hypertension may be more strongly related to hearing-related changes in the brain than in the cochlea.

Self-reported and cotinine-verified smoking and increased risk of incident hearing loss

We examined the associations of smoking status and urinary cotinine levels, an objective measure of smoking, with the development of new-onset HL. This cohort study was performed in 293,991 Korean adults free of HL who underwent a comprehensive screening examination and were followed for up to 8.8 years. HL was defined as a pure-tone average of thresholds at 0.5, 1.0, and 2.0 kHz ≥ 25 dB in both ears. During a median follow-up of 4.9 years, 2286 participants developed new-onset bilateral HL. Self-reported smoking status was associated with an increased risk of new-onset bilateral HL. Multivariable-adjusted HRs (95% CIs) for incident HL comparing former smokers and current smokers to never-smokers were 1.14 (1.004-1.30) and 1.40 (1.21-1.61), respectively. Number of cigarettes, pack-years, and urinary cotinine levels were consistently associated with incident HL. These associations were similarly observed when introducing changes in smoking status, urinary cotinine, and other confounders during follow-up as time-varying covariates. In this large cohort of young and middle-aged men and women, smoking status based on both self-report and urinary cotinine level were independently associated with an increased incidence of bilateral HL. Our findings indicate smoking is an independent risk factor for HL.

The relationship between chronic exposure to arsenic through drinking water and hearing function in exposed population aged 10-49 years: A cross-sectional study

It has been documented that arsenic has a potential risk to human health and identified as a risk factor for hearing impairment. However, there are few studies that confirm the ototoxic effect of arsenic, especially on the human auditory system. Therefore, the current study was conducted to investigate the correlation between auditory thresholds at different frequencies (0.25, 0.5, 1, 2, 4 and 8 kHz) and arsenic levels in drinking water samples. A total of 240 people, divided into two equal groups: exposed and reference, were selected for the auditory tests. It should be noted that, at frequencies from 0.25 to 1 kHz, no hearing loss was observed in the both groups. Based on the results, no significant correlations (p > 0.05) were found between hearing thresholds and confounding variables including gender and BMI. However, smoking and age are known to be the main variables for hearing loss in univariate regression analysis. In the case of age, the hearing loss risk in the older participants was increased compared with the younger participants (4 kHz (OR =1.09; 95% CI: 1.04, 1.13) and 8 kHz (OR =1.12; 95% CI: 1.06, 1.18)). Smoking habits had significant associations with hearing loss risk at 4 kHz (OR = 3.48; 95% CI: 1.47, 8.22) and 8 kHz (OR = 3.01; 95% CI: 1.14, 7.95). The multivariate regression analysis showed that age, smoking status, and exposure to arsenic were significantly associated with increased risk of hearing loss. Moreover, no statistically significant correlation (p˃0.05) was observed between arsenic exposure and hearing loss in the logistic regression model compared to the reference group. These outcomes suggest that further investigation and cohort studies with a larger number of participants should be conducted to find an association between arsenic exposure and hearing loss in general population.

Hearing impairment prevalence and risk factors among adults in rural China: a population-based cross-sectional study

Objective: Over the past few decades, the prevalence of hearing impairment (HI) has rapidly increased, making HI one of the most common causes of disability, globally. The burden of HI is particularly heavy in low socioeconomic status populations. Despite extensive research into the range of HI prevalence in low socioeconomic status populations, worldwide, population-based studies have been rare. Thus, we explored HI prevalence and risk factors among low-income, middle-aged and elderly individuals in Tianjin, China.Method: Between September and November 2013, 2351 rural residents in Tianjin, China were recruited into the study. All participants completed questionnaire surveys, physical examinations, laboratory examinations, and hearing tests. HI was measured using pure-tone audiometry, and audiologists determined the final diagnoses.Results: Among the 2351 participants, ≥45 years old, the prevalence of HI was 49.3%, including 54.3% among men and 46.0% among women. Slight HI accounted for the largest proportion of individuals (40.7%). The risk of HI among men was 32.9% higher than among women. Moreover, the risk of HI increased with increasing age. Compared with the 45-54-year-old group, the risk of HI in individuals in the 55-64-year-old, 65-74-year-old, and ≥75-year-old groups were 25.8%, 109.9%, and 373.7% higher, respectively. Moreover, increased with each 1-mmHg SBP, the risk of HI increase 0.7% (95%CI: 1.001-1.013; P = 0.017); while increased with each 1-mmHg DBP, the risk of HI decrease 1.7% (95%CI: 0.973-0.993; P = 0.001)Conclusions: The burden of HI in rural northern China is heavy, especially among elderly men and people with elevated systolic blood pressure (SBP). Addressing HI prevention is critical for reducing the HI burden and improving quality of life.

An Exploratory Study of Early Auditory Evoked Potentials in Cannabis Smokers

Purpose Cannabis is widely used for medicinal and recreational purposes. Studies have evaluated its health benefits and consequences, although there is limited work on its effects on the auditory system. In this exploratory study, we evaluate the effects of cannabis smoking on early auditory evoked potentials. Method We investigated auditory brainstem response (ABR) and electrocochleography waveforms in 18 cannabis smokers (44% women, 54% men; M _age = 23.06 years, range: 21-28 years) and 19 nonsmoker controls (63% women, 37% men; M _age = 23.74 years, range: 21-33 years). Threshold ABRs were recorded using rarefaction clicks at a rate of 17.7/s from 80 dB nHL to Wave V threshold. Resulting amplitudes and latencies for Waves I, III, and V were compared via independent-samples t tests. Electrocochleograms obtained with 90 dB nHL (7.1/s) alternating clicks were assessed for summating and compound action potentials, which were compared between groups using independent-samples t tests. Results ABR Wave I amplitudes were significantly lower in smokers (M = 0.14 μV, SD = 0.11) compared to nonsmokers (M = 0.21 μV, SD = 0.10, p = .039) at 80 dB nHL. Wave V latencies were significantly delayed in smokers at 80 dB nHL. Wave I and III latencies did not differ significantly between the two groups. Summating potential/compound action potential ratios were significantly elevated in smokers (M = 0.30, SD = 0.04) versus nonsmokers (M = 0.21, SD = 0.05, p = .042). Conclusion We identified significant differences in electrophysiological outcomes between cannabis smokers and nonsmokers. Cannabis smoking may have a subtle neurotoxic effect on the auditory system. Larger confirmatory studies are warranted.

Association between hypertension, dyslipidemia, and diabetes and prevalence of hearing impairment in Japan

Epidemiological information regarding the relationship between hypertension, dyslipidemia, and/or diabetes and hearing impairment (HI) has been controversial. The present cross-sectional study investigated this issue in Japan. The subjects were 371 men and 639 women aged 36‒84 years. Hypertension was defined as systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or current use of antihypertensive medication. Dyslipidemia was defined as a serum low-density lipoprotein cholesterol concentration ≥140 mg/dL, high-density lipoprotein cholesterol concentration <40 mg/dL, triglyceride concentration ≥150 mg/dL, or current use of cholesterol-lowering medication. Diabetes was defined as a fasting plasma glucose level ≥126 mg/dL, hemoglobin A1c level ≥6.5%, or current use of diabetic medication. HI was defined as present when subjects did not respond to a pure-tone average of >25 dB HL in the better hearing ear. Adjustments were made for age, smoking, alcohol consumption, body mass index, household income, and education. The prevalence of HI was 31.5% in men and 20.8% in women. In men, hypertension, but not dyslipidemia or diabetes, was independently positively associated with HI: the adjusted prevalence ratio (PR) was 1.52 (95% CI: 1.07‒2.16). Having at least two cardiovascular risk factors among hypertension, dyslipidemia, and diabetes was independently positively related to HI: the adjusted PR was 1.82 (95% CI: 1.11‒2.99, P for trend = 0.02). Such positive associations were not found in women. Hypertension and having at least two cardiovascular risk factors may be positively associated with HI in men only.

Audiologic profile of the jackson heart study cohort and comparison to other cohorts

OBJECTIVES/HYPOTHESIS

The objective of this study was to determine the audiological profile of an African American cohort, identify related factors, and compare them to other datasets.

STUDY DESIGN

Cross-sectional, longitudinal cohort study.

METHODS

The Jackson Heart Study (JHS) is a longitudinal cohort study of 5,306 African Americans living in the metropolitan Jackson, Mississippi area, with a focus on cardiometabolic health. The JHS Hearing Study (n = 1,314) was implemented to measure the prevalence of hearing, tinnitus, and balance outcomes and relationship to predictor variables. Here we present prevalence and covariate relationships in comparison to the Epidemiology of Hearing Loss Study and the National Health and Nutrition Examination Survey.

RESULTS

The prevalence of self-reported hearing difficulty was 38.1% (n = 500). The prevalence of hearing loss based on audiometric pure tone threshold average (0.5, 1.0, 2.0, 4.0 kHz) of the better ear was 19.8% (n = 260) and for the worse ear 29.8% (n = 392). The prevalence of tinnitus was 29.5% (n = 388) and balance dysfunction 24.1% (n = 317). Relationships of hearing loss to demographic, cardiometabolic, and audiologic variables are presented.

CONCLUSIONS

These results demonstrate that hearing loss, tinnitus, and balance dysfunction are common issues affecting adult African Americans, and that hearing loss is related to numerous modifiable and nonmodifiable risk factors. Furthermore, our findings are consistent with lower prevalence of hearing loss in African Americans compared to the non-African American populations. However, despite the lower audiometric evidence of hearing loss, nearly 40% of participants reported hearing difficulty.

LEVEL OF EVIDENCE

2b Laryngoscope, 129:2391-2397, 2019.

Pure Tone Audiometry Threshold Changes for 10 Years in the Same Individuals of General Population: A Retrospective Cohort Study

Objectives:

The objectives of this study were to measure the changes in hearing thresholds in the same individuals during a period of 10 years and suggest a clinical reference for the threshold changes by aging.

Methods:

In this retrospective cohort study, we used regular health checkup data including 2 pure tone audiometry results with a 10-year interval in the same individuals from 1288 subjects. The subjects’ data including demographics, smoking habits, and the diagnosis of chronic diseases were used.

Results:

Age, male gender, smoking, and osteoporosis were identified as factors affecting age-related hearing loss (ARHL). The sole effect of aging on ARHL for 10 years according to age groups and genders was as follows: a loss of 1.4 dB in 20s, 4.0 dB in 30s, 5.0 dB in 40s, 8.2 dB in 50s, and 11.2 dB in 60s of males compared to a loss of 2.3 dB in 20s, 2.9 dB in 30s, 5.1 dB in 40s, 6.5 dB in 50s, and 9.4 dB in 60s of females.

Conclusions:

We could demonstrate the actual effect of aging on ARHL, and it can be used as a clinical reference. Hearing ability decreases more in males than females but seems to decrease exponentially with age in both males and females.

Association of household income and education with prevalence of hearing impairment in Japan

OBJECTIVES/HYPOTHESIS

Epidemiological information regarding the relationship between household income and education and hearing impairment (HI) is limited. The present cross-sectional study investigated this issue in Japan.

STUDY DESIGN

Cross-sectional investigation.

METHODS

Study subjects were 371 men and 639 women aged 36 to 84 years. A self-administered questionnaire was used. Audiological assessment was performed by pure-tone audiometry. HI was defined as present in subjects who did not respond to a pure-tone average of >25 dB HL in the better hearing ear according to the World Health Organization standard. Adjustment was made for age, smoking status, alcohol consumption, hypertension, dyslipidemia, diabetes mellitus, and body mass index.

RESULTS

The prevalence of HI was 31.5% in 371 men and 20.8% in 639 women. In men, a slight inverted J-shaped association was observed between household income and HI, compared with a household income of <3 million yen per year. A household income of 3 to 5 million yen, but not of 5 million yen or more, was independently inversely associated with the prevalence of HI; the prevalence ratio for 3 to 5million yen was 0.73 (95% confidence interval: 0.54-0.999). After adjustment for confounding factors, no relationship was found between household income and the prevalence of HI in women. There were no associations between educational level and the prevalence of HI in either men or women in the multivariate model.

CONCLUSIONS

Our results suggest that medium, but not high, household income may be associated with a lower prevalence of HI only in men.

LEVEL OF EVIDENCE

2b Laryngoscope, 129:2153-2157, 2019.

Longitudinal Pure-Tone Threshold Changes in the Same Subjects: Analysis of Factors Affecting Hearing

OBJECTIVES

To investigate the change of hearing threshold over time and analyze factors that could affect hearing, this longitudinal study of pure-tone threshold changes in the same subjects at a 9-year interval was performed.

STUDY DESIGN

Retrospective longitudinal study in a single center (n = 1,978).

METHODS

A total of 1,978 subjects were included; they received pure-tone audiometry at a 9-year interval. The degree of the threshold changes was examined and compared between age groups. The subjects' data, such as the level of cholesterol, were analyzed to find risk factors on hearing.

RESULTS

The average of the threshold changes was 3.35 dB in the 20s to 30s; 4.38 dB in the 30s to 40s; 5.75 dB in the 40s to 50s; 7.21 dB in the 50s to 60s; and 10.00 dB in the 60s to 70s (all P < 0.05). If the low-density lipoprotein cholesterol (LDL-C) was maintained below 100 mg/dl, the difference in the weighted four-frequency average was 5.45 dB, whereas it was 6.15 dB in the subjects whose LDL-C was over 100 mg/dl (P = 0.032, age-adjusted). In current smokers, the thresholds increased more than in never- or ex-smokers (P = 0.026 in the weighted four-frequency average and P = 0.011 at 8,000 Hz, age-adjusted).

CONCLUSION

The degree of the threshold changes exhibited an exponential increase with age. Cessation of smoking is advisable to prevent increased aggravation of hearing. Strict management of the low-density lipoprotein cholesterol may have a positive effect on hearing.

LEVEL OF EVIDENCE

3 Laryngoscope, 129:470-476, 2019.

Susceptibility of Diabetic Mice to Noise Trauma

Diabetes can lead to many end-organ complications. However, the association between diabetes and hearing loss is not well understood. Here, we investigated the effect of noise exposure on diabetic mice compared with wild-type mice. Hearing threshold shifts, histopathologic changes in the cochlea, and inflammatory responses were evaluated over time. After noise exposure, more severe hearing threshold shifts, auditory hair cell loss, and synaptopathies were notable in diabetic mice compared with wild-type mice. Moreover, increased inflammatory responses and reactive oxygen species production were observed in the ears of diabetic mice. The results demonstrated that diabetic mice are more susceptible to noise trauma.