Increased risk of getting sudden sensorineural hearing loss in patients with chronic kidney disease: a population-based cohort study

The construction and validation of prognostic prediction model for sudden sensorineural hearing loss in middle-aged and elderly people

OBJECTIVE

Idiopathic sudden sensorineural hearing loss (ISSNHL), as an otologic emergency, is commonly encountered and its prevalence has been climbing every year recently. To our knowledge, the prognosis of middle-aged and elderly patients is worse than that of young patients. Previous researches mainly focused on the adult population, which was considered as prognostic models who performed hearing recovery in ISSNHL. However, few studies regarding the middle-aged and elderly population who are regarded as prognostic models have been reported. Therefore, we aim to construct and validate a nomogram-based prognostic prediction model, which can provide a reference for the prognostic assessment in the middle-aged and elderly patients with ISSNHL.

METHOD

A total of 371 middle-aged and elderly ISSNHL patients who were admitted to the Department of Otolaryngology-Head and Neck Surgery, Yanbian Hospital, Yanbian University, from April 2018 to April 2023 were enrolled in the study. All subjects were randomly divided into two groups including training group (n = 263) and validation group (n = 108). Lasso regression and multi-factor logistic regression were jointly utilized to screen out prognosis-related independent risk factors and establish a nomogram-based risk prediction model. The accuracy and clinical application value of the model were evaluated by combining the Bootstrapping method and k-fold cross-validation, plotting the receiver operating characteristic  (ROC)  curve, calculating the area under the ROC curve (AUC), plotting the decision curve analysis (DCA), and the calibrating curve.

RESULT

We used the method of lasso regression combined with multivariate logistic regression and finally screened out eight predictors (including age, number of affected ears, degree of hearing loss, type of hearing curve, duration of disease, presence of vertigo, diabetes, and lacunar cerebral infarction) that were included into the nomogram. The C-index were 0.823 [95% CI (0.725, 0.921)] and 0.851 [95% CI (0.701, 1.000)], and the AUC values were 0.812 and 0.823 for the training and validation groups, respectively. The calibration curve for the validation group was approximately conformed to that for the modeling group, indicating favorable model calibration. The DCA results revealed the modeling group (3%-86%) and the validation group (2%-92%) showed significant net clinical benefit under the majority of thresholds.

CONCLUSION

This study developed and validated a nomogram-based prognostic prediction model which based on the eight independent risk factors mentioned above. The predictors are conveniently accessible and may assist clinicians in formulating individualized treatment strategies.

A Systematic Review on Heritability of Sudden Sensorineural Hearing Loss

OBJECTIVE

To assess the evidence supporting the heritability and genetic basis of sudden sensorineural hearing loss (SSNHL).

DATA SOURCE

Records were extracted from PubMed, Scopus, and Cochrane databases.

REVIEW METHODS

The protocol was registered on PROSPERO (CRD42022357389) and includes a systematic review on the genetic contribution to SSNHL. The search strategy yielded 1.483 articles from electronic databases. After quality assessment, 34 records were selected, including 369.650 patients with SSNHL from nine prevalence studies, two familial aggregation studies, one twin study, and 22 genetic studies. The prevalence of SSNHL was calculated from data on its incidence from population-based studies (period prevalence). To evaluate the heritability of SSNHL, the sibling recurrence risk ratio (λs) was calculated, by comparing the prevalence of SSNHL among siblings within the same generation to the estimated prevalence in the overall population. Genetic variants were grouped, based on the pathological mechanism related to SSNHL.

RESULTS

The prevalence of SSNHL ranged from 0.1% to 0.0003% in America to 0.12%-0.0093% in Asia. The estimated sibling recurrence risk ratio for SSNHL (λs  = 20.8-83.3) supports a significant familial aggregation. Although several genetic variants were reported to be associated with SSHL in controlled studies, neither was replicated in an independent cohort.

CONCLUSIONS

Evidence supporting heritability of SSNHL is limited to epidemiological studies showing prevalence differences across different populations and familial aggregation. Genetic studies are of low quality and they lack replication cohort to confirm their findings. According to its low prevalence, exome or genome sequencing familial-based studies are needed to identify rare genetic variants in SSNHL.

LEVEL OF EVIDENCE

NA Laryngoscope, 2024.

Treatment outcomes for idiopathic sudden sensorineural hearing loss in dialysis patients

Idiopathic sudden sensorineural hearing loss (ISSNHL) is challenging for both nephrologists and otolaryngologists treating patients undergoing dialysis. This single-center, retrospective, observational study investigated the treatment outcomes of patients with ISSNHL undergoing dialysis, enrolling 700 patients (47 undergoing and 653 not undergoing dialysis) diagnosed with ISSNHL between January 2005 and December 2021 at Asan Medical Center, Republic of Korea. To balance pre-existing clinical characteristics, 1:5 propensity score matching (PSM) was performed with the patients who were not undergoing dialysis. Treatment included high-dose systemic steroid therapy or intra-tympanic steroid injections. The pure tone average of the groups was compared before and 2 weeks and 2 months after treatment. The hearing-improvement degree was evaluated using Siegel's criteria. Before PSM, age, prevalence of diabetes or hypertension, initial hearing threshold at each frequency level (0.5, 1, 2, and 4 kHz), and treatment strategies exhibited significant between-group differences. However, in the PS-matched cohort, none of the confounders showed significant between-group differences. Two months after steroid treatment, the non-dialysis patient group demonstrated significantly higher average improvement in pure tone audiometry (P = 0.029) and greater percentage of complete response according to Siegel's criteria. This study suggests that treatment outcomes for ISSNHL are significantly poorer for patients undergoing than for those not undergoing dialysis.

Association between air pollution and sudden sensorineural hearing loss (SSHL): A systematic review and meta-analysis

Recent studies have indicated that air pollution (AP) has harmful effects on hearing and ear diseases such as Sudden Sensorineural Hearing Loss (SSHL). The purpose of this study was to evaluate the impact of exposure to AP on SSHL incidence. Valid electronic databases were searched to retrieve studies published until December 1, 2022, using appropriate keywords. The result of the search was 1146 studies, and after screening according to the defined criteria, in total 8 studies were obtained. The risk of bias (ROB) in the studies and their quality were assessed. Finally, the meta-analysis with a significance level of 5% was performed. The findings revealed that the mean level of SO2, CO, NO2, and PM10 in the patient group was more than that of the control group, and p-values were 0.879, 0.144, 0.077, and 0.138, respectively. There was an indirect relation between air pollutants and SSHL, and PM2.5 showed a significant effect (p < 0.05). Given the limited research and the use of different statistical methods, more research is suggested to confirm this association and to determine the mechanisms by which AP exposure may cause SSHL.

Association between Chronic Kidney Disease and Sudden Sensorineural Hearing Loss: A Longitudinal Follow-Up Studies Using ICD-10 Codes in a National Health Screening Cohort

This study aims to investigate the association between chronic kidney disease (CKD) and sudden sensorineural hearing loss (SSNHL) using a population-based cohort study. We used data from the Korean National Health Insurance Service-Health Screening Cohort. Participants were selected based on diagnosis and treatment codes, and CKD participants were 1:4 matched with control participants. Covariates, including demographic and lifestyle factors, and comorbidities were considered in the analysis. We calculated the incidence rate and hazards ratio of SSNHL. A total of 16,713 CKD participants and 66,852 matched controls were enrolled. The CKD group had a higher incidence rate of SSNHL compared to the control group at 2.16 and 1.74 per 1000 person-years, respectively. The CKD group exhibited a higher risk for SSNHL compared to the control group with adjusted HR 1.21. In the subgroup analysis, the presence of cardiovascular risk factors was associated with a diminished effect of CKD on the risk of developing SSNHL. This study provides strong evidence of an association between CKD per se and an increased risk of SSNHL even after adjusting for various demographic and comorbidity factors. The findings suggest that CKD patients may require more comprehensive monitoring for hearing loss.

Comorbidities and laboratory changes of sudden sensorineural hearing loss: a review

Sudden sensorineural hearing loss (SSNHL) is defined as an abrupt hearing loss of more than 30 dB in three contiguous frequencies within 72 h. It is an emergency disease requiring immediate diagnosis and treatment. The incidence of SSNHL in Western countries' population is estimated between 5 and 20 per 1,00,000 inhabitants. The etiology of SSNHL remains unknown. Due to the uncertainty of the cause of SSNHL, at present, no specific treatment targets the cause of SSNHL, resulting in poor efficacy. Previous studies have reported that some comorbidities are risk factors for SSNHL, and some laboratory results may provide some clues for the etiology of SSNHL. Atherosclerosis, microthrombosis, inflammation, and the immune system may be the main etiological factors for SSNHL. This study confirms that SSNHL is a multifactorial disease. Some comorbidities, such as virus infections, are suggested to be the causes of SSNHL. In summary, by analyzing the etiology of SSNHL, more targeting treatments should be used to achieve a better effect.

Association of Chronic Kidney Disease with Prior Tinnitus: A Case-Control Study

This population-based, case−control study aims to explore the relationship between prior tinnitus and the occurrence of chronic kidney disease (CKD) using a nationwide, population-based cohort study. We used data from the Taiwan National Health Insurance Research Database to explore the association of CKD with tinnitus. We identified 15,314 patients aged ≥40 years old with a first-time diagnosis of CKD as the cases. We used propensity-scored matching to select 45,942 controls (1:3 ratio). We performed multivariate logistic regression to estimate the odds ratio (OR) of a prior tinnitus diagnosis among the CKD group vs. the control group. Analysis showed that 770 (1.26%) out of the 61,256 sampled patients had previously diagnosed tinnitus. Chi-square testing revealed a significant difference in the rate of previously diagnosed tinnitus between cases and controls (3.86% vs. 0.93%, p < 0.001). Univariate logistic regression analysis showed an OR of prior tinnitus for cases of 10.249 (95% confidence interval (CI): (8.662~12.126)) relative to controls. In adjusted analysis, cases were more likely than controls to have a prior diagnosis of tinnitus (OR = 10.970, 95% CI = 9.255~13.004, p < 0.001) after adjusting for age, sex, monthly income, geographic location, urbanization level, hypertension, diabetes, coronary heart disease, hyperlipidemia, obesity, and autoimmune disease. Our study shows that CKD patients have a higher likelihood of having suffered from tinnitus before CKD was diagnosed, but we have no data suggesting that tinnitus is a predictor of subsequent CKD. Patients diagnosed with tinnitus may benefit from proactive measures to prevent CKD and detect it early through lifestyle modifications and regular renal function examinations, regardless of CKD-related symptoms.

High Frequency Hearing Loss in Chronic Renal Disease: A Cross-Sectional Study

Introduction Chronic kidney disease (CKD) patients face multiple complications. One of them is involvement of the auditory system and it deserves more attention than is paid by the current approaches as hearing loss has major repercussions on the quality of life. Early detection can prevent further deterioration of hearing and improve the quality of life of patients suffering from CKD. Material and methods The high frequency (8-18 kHz) audiometry with pure tones was performed in 82 patients with CKD and compared with age and sexes matched healthy control group of 90 patients. Individual ear were used for statistical calculations. Results This study clearly observed that the hearing thresholds for frequencies 8-18 kHz increased in CKD patients when compared to sex and aged matched healthy control group, the thresholds significantly increased in CKD with diabetes mellitus as compared to nondiabetic with CKD. The high frequency thresholds significantly increased in patients on hemodialysis, and were significantly correlated with age, stage of CKD and duration of CKD. Conclusion This study highlights the presence of high frequency (8-18 kHz) hearing loss in patients of CKD. The severity is significantly correlated with age, stage and duration of CKD.

Prognostic Factors Associated with Recovery from Recurrent Idiopathic Sudden Sensorineural Hearing Loss: Retrospective Analysis and Systematic Review

Although idiopathic sudden sensorineural hearing loss (ISSNHL) is uncommon, recurrent ISSNHL is even rarer. The knowledge about factors associated with patient recovery from recurrent episodes is needed to counsel and treat the patients. Medical records of patients admitted for high dose oral steroid therapy for recurrent ISSNHL between January 2009 and December 2021 were reviewed. Their demographic and clinical characteristics, co-morbid symptoms, and audiologic results were analyzed. The 38 patients admitted for treatment of recurrent ISSNHL included 14 men and 24 women. Recovery rates after the first and recurrent episodes of ISSNHL were 78.9% and 63.2%, respectively. Patients who recovered after recurrent episodes showed significantly higher rates of ear fullness symptoms and early treatment onset than those who did not recover (p < 0.05 each). Of the 30 patients who recovered after the first episode, those who had ear fullness symptoms (p < 0.05, odds ratio (OR) 0.1, 95% confidence interval (CI) 0.01−0.76) and who showed a lower initial hearing threshold (p < 0.05, OR 1.06, 95% CI 1.01−1.12) during the recurrent episode showed significantly better or similar recovery than after the first episode. Ear fullness symptoms and less initial hearing loss were associated with a more favorable prognosis after intial than after recurrent ISSNHL.

Association between Statin Use and Sensorineural Hearing Loss in Type 2 Diabetic Patients: A Hospital-Based Study

Statins have emerged as protective agents against sensorineural hearing loss (SNHL) associated with dyslipidemia, but the effects of statins on SNHL are not consistent. The purpose of this study was to investigate the association between statin use and the risk of SNHL using a hospital cohort. This nested case-control study included type 2 diabetic patients over the age of 18 years without a history of hearing loss. Of these, 1379 patients newly diagnosed with SNHL or tinnitus were classified as cases, and 5512 patients matched to the cases based on age, sex, and index year were classified as controls. Chi-squared tests were used to compare categorical variables between the two groups. Odds ratios (ORs) and adjusted odds ratios (AOR) were calculated from univariate and multivariable unconditional logistic regression analyses, respectively. There was a significant difference in the prevalence of statin use between the cases and controls (53.7% vs. 61.2%, respectively; p < 0.001). The use of statins in type 2 diabetic patients significantly reduced the risk of SNHL or tinnitus by 24.8% (95% CI 14.2–34.1%, p < 0.001) after controlling for confounders. Similar results were found for the association between statin use and SNHL (AOR = 0.706; 95% CI 0.616–0.811, p < 0.001). The protective effects of statins against SNHL were consistent regardless of age and sex. The use of statins for type 2 diabetic patients was significantly associated with a reduced risk of SNHL, regardless of age and sex. Further studies are needed, especially large cohort studies, to evaluate the long-term protective effects of statins.

Clinical features and hearing prognosis of idiopathic sudden sensorineural hearing loss in patients undergoing hemodialysis: A retrospective study

BACKGROUND

Patients undergoing hemodialysis (HD) tend to experience hearing loss, including idiopathic sudden sensorineural hearing loss (ISSHL). However, little is known about the relationship between HD and ISSHL.

OBJECTIVE

To investigate the effects of HD on the hearing level and the treatment prognosis of ISSHL.

METHODS

We reviewed the medical records of 23 patients with ISSHL receiving HD treatment (HD group) and 101 patients with ISSHL not receiving HD treatment (non-HD group), and assessed clinical features, results of audiometric tests and blood examination results.

RESULTS

Statistically significant differences were not observed in pretreatment hearing level and hearing recovery of the ear affected with ISSHL between the two groups (P > .05). Conversely, hearing thresholds in the unaffected ear were statistically different (P < .0001), and the hearing thresholds of the HD groups were significantly increased compared with those of the non-HD groups, especially at high frequency. In addition, patients with renal dysfunction not receiving HD treatment showed similar hearing thresholds in the unaffected ear when compared with patients receiving HD treatment.

CONCLUSION

HD itself did not influence the treatment prognosis of ISSHL. Renal dysfunction itself, and not HD treatment, worsened the hearing level. As similar treatment results are expected, standard treatment should be administered to patients undergoing HD.

LEVEL OF EVIDENCE

3b.

Design and methodology of the chronic kidney disease as a dysmetabolic determinant of disability among older people (CKD-3D) study: a multicenter cohort observational study

Background

Chronic kidney disease (CKD) is a common condition in older people and represents a global health issue since it increases the risk of associated comorbidities and all-cause mortality. Furthermore, older people with reduced renal function might be at higher risk for developing functional limitation and disability. Moreover, the current creatinine-based measures of renal function are influenced by several factors in older population. The aims of the CKD-3D project are to perform an observational study to expand the knowledge about CKD-disability relationship and to investigate the use of novel biomarkers of kidney function.

Methods

An observational, multicenter, prospective cohort study will be conducted in 75 + old patients consecutively admitted to acute care wards of geriatric medicine at participating hospitals. The study planned to enroll 440 patients undergoing clinical and laboratory evaluations at baseline and after 12 months. Face-to-face follow-up at 6 months and telephone follow-up at 3 and 9 months will be carried out. Comprehensive Geriatric Assessment (CGA) and the measurement of Cystatin C, Beta-Trace Protein and Beta2-Microglobulin levels will be included.

Discussion

This study will provide useful information to prevent CKD-related disability by collecting real-life data over 1-year period. The combined approach of CGA and the investigation of innovative existing biomarkers will make it possible to develop new recommendations and guidelines for a patient-centered approach. It is believed that such a study may lead to an improvement of knowledge on CKD in elderly patients and may also have implications in daily clinical practice and in decision-making process.

Increased incidence of unilateral sudden sensorineural hearing loss in patients with hematological malignancies requiring hematopoietic stem cell transplantation

Haematopoietic stem cell transplantation (HSCT) may dramatically alter the immunity of a recipient. Transient immunodeficiency that occurs before and after HSCT could be associated with the development of sudden sensorineural hearing loss (SSNHL), which is presumed to be often due to viral aetiology. We found an incidence of SSNHL of 29.4 per 10,000 person-years in patients receiving HSCT, 12-fold higher than reported for background population incidence. Development of SSNHL tended to cluster early after diagnosis of haematological malignancies, rather than around date of treatment with HSCT. Increased risk of unilateral SSNHL in patients with haematological malignancy may relate to underlying disease rather than treatment.

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.

Health Status of Adults with Hearing Loss in the United States

Purpose: The purpose of this study was to identify the current health status of adults in the United States with self-reported hearing loss and compare it with US adults with a self-reported excellent or good hearing in three areas: (1) chronic disease states and general health status, (2) medical screening behaviors, and (3) lifestyle behaviors. Methods: A secondary data analysis was conducted using the 2014 data set from the National Health Interview Survey (NHIS), specifically the Sample Adult Public Use File (samadult). For this questionnaire set, one adult per family was randomly selected. This individual self-reported their response to the questionnaire items. Binary regressions were used to analyze the odds ratio to find differences for selected disease states, screenings, and lifestyle behaviors. Respondents were grouped into one of four categories: excellent/good hearing, a little trouble hearing, moderate/a lot of trouble hearing, and deaf. Results: The excellent/good hearing group was used as the comparison group for the other three levels of hearing. There are many differences in likelihood to self-report disease states; the greatest increased likelihoods include tinnitus and heart disease, with tinnitus being 8.6 times more likely for those who identified as having moderate/a lot of hearing loss. Those with any level of hearing loss were 3 to 5 times more likely to self-report heart disease. Regarding lifestyle factors, individuals with any level of hearing loss were less likely to consume alcohol and 2.5 to 9 times more likely to be unable to engage in moderate or vigorous activity on a weekly basis, respectively. Conclusions: There is a difference in the health status of individuals with hearing loss across all three areas examined (chronic disease states and general health status, medical screening behaviors, and lifestyle behaviors), and those differences vary based on level of hearing loss, the most notable being the self-reported inability to engage in moderate and vigorous physical activity. Disproportionate rates of tinnitus and heart disease were evident in all levels of hearing loss but most notable in those identifying as having moderate/a lot of trouble hearing. Further interdisciplinary research is necessary to improve the health of individuals with all levels of hearing loss, increase awareness of the hearing/health connection, and decrease hearing loss in general.

Investigation of the relationship between sensorineural hearing loss and associated comorbidities in patients with chronic kidney disease: A nationwide, population-based cohort study

Hearing impairment was observed in patients with chronic kidney disease (CKD). Our purpose was to investigate the relationship between sensorineural hearing loss (SNHL) and associated comorbidities in the CKD population. We conducted a retrospective, population-based study to examine the risk of developing SNHL in patients with CKD. Population-based data from 2000–2010 from the Longitudinal Health Insurance Database of the Taiwan National Health Insurance Research Database was used in this study. The population sample comprised 185,430 patients who were diagnosed with CKD, and 556,290 without CKD to determine SNHL risk factors. Cox proportional hazard regression analysis demonstrated the CKD group had a significantly increased risk of SNHL compared with the non-CKD group [adjusted hazard ratio (HR), 3.42; 95% confidence interval (CI), 3.01–3.90, p < 0.001]. In the CKD group, the risk of SNHL (adjusted HR, 5.92) was higher among patients undergoing hemodialysis than among those not undergoing hemodialysis (adjusted HR, 1.40). Furthermore, subgroup analysis revealed an increased risk of SNHL in patients with CKD and comorbidities, including heart failure (adjusted HR, 7.48), liver cirrhosis (adjusted HR, 4.12), type 2 diabetes mellitus (adjusted HR, 3.98), hypertension (adjusted HR, 3.67), and chronic obstructive pulmonary disease (adjusted HR, 3.45). CKD is an independent risk of developing SNHL. Additionally, hemodialysis for uremia can increase the risk of SNHL. Cardiovascular, lung, liver, and metabolic comorbidities in CKD patients may further aggravate the risk of SNHL by inter-organ crosstalk. We should pay attention to SNHL in this high-risk population.

Acute sensorineural hearing loss in hemodialysis patients

Background: Approximately, 30-40% of patients experienced hearing loss under regular hemodialysis.Objective: This study reviewed our experience on treating acute hearing loss in patients under regular hemodialysis over the past two decades.Methods: Twenty-six patients having acute hearing loss under hemodialysis were divided into two groups based on their etiologies. Sixteen patients (16 ears) with sudden sensorineural hearing loss (SSHL) were assigned to Group A and 10 patients (13 ears) with endolymphatic hydrops (EH) were assigned to Group B.Results: No significant difference was noted between Groups A and B, regardless of hemodialysis duration, clinical manifestation, underlying systemic diseases, blood examination, and vestibular test battery. In contrast, serum osmolality was significantly lower in Group B (292 ± 11 mOsm/kg) than in Group A (310 ± 11 mOsm/kg). Furthermore, Group B (40 ± 14 dB) had better mean hearing level than Group A (87 ± 21 dB) in the initial audiogram, and a higher hearing improvement rate (69%) than Group A (19%).Conclusions and significance: Both SSHL and EH are major causes for precipitating acute hearing loss in hemodialysis patients. Compared to SSHL, the less deteriorated MHL and lower serum osmolality in EH provide two clues for differentiating acute hearing loss in hemodialysis patients.

Association between Sudden Sensorineural Hearing Loss and Preexisting Thyroid Diseases: A Nationwide Case-Control Study in Taiwan

Background: Little evidence is available about the risk of sudden sensorineural hearing loss (SSNHL) in patients with thyroid diseases. We assessed whether a diagnosis of thyroid disease, particularly hyperthyroidism or hypothyroidism, is associated with SSNHL risk in an Asian population. Material and Methods: This case-control study was conducted with population-based data from Taiwan’s National Health Insurance Research Database from January 2000 to December 2013. The case group comprised 3331 adult patients with newly diagnosed SSNHL, and four controls without SSNHL for each case matched by sex, age, monthly income, and urbanization level of residence. Underlying Thyroid diseases were retrospectively evaluated in the case and control groups. Multivariate logistic regression analyses were used to explore relations between thyroid diseases and SSNHL. Results: Of the 3331 cases, 5.7% had preexisting thyroid diseases, whereas only 4.0% of the 13,324 controls had the same condition. After adjustment for sex, age, monthly income, urbanization level of residence, history of hypertension, diabetes mellitus, chronic otitis media, and hyperlipidemia, associations were identified between a history of either hypothyroidism (adjusted odds ratio [AOR], 1.54; 95% CI, 1.02–2.32; p = 0.042) or hyperthyroidism (AOR, 1.41; 95% CI, 1.07–1.85; p = 0.015) and an elevated risk of SSNHL. In subgroup analysis, the correlation between hypothyroidism and increased SSNHL risk remained significant only for patients aged over 50 years (AOR, 1.61; 95% CI, 1.01–2.57; p = 0.045), and that between hyperthyroidism and SSNHL was significant only for female patients (AOR, 1.48; 95% CI, 1.09–2.01; p = 0.012). Treatment for hypothyroidism and hyperthyroidism did not alter the association in subgroup analyses. Conclusion: Preexisting hypothyroidism and hyperthyroidism appear associated with SSNHL susceptibility in Taiwan. Physicians should be wary of this elevated risk of SSNHL among patients with previously diagnosed thyroid dysfunction, especially women and patients aged more than 50 years.

Epidemiology of Clinically Significant Tinnitus: A 10-Year Trend From Nationwide Health Claims Data in South Korea

OBJECTIVES

Prevalence of tinnitus has been reported to vary according to the target population and definition of tinnitus. To improve the understanding of tinnitus, authors used the nation-wide health claim data to study the tinnitus in the entire population of South Korea.

STUDY DESIGN

Retrospective big data review.

SETTING

Analysis of big data from the National Health Information Database.

PATIENTS

Patients diagnosed with tinnitus according to International Classification of Diseases code 10th edition (ICD-10) and requested to receive National Health Insurance claim at least once from January 2006 to December 2015.

INTERVENTION

None.

MAIN OUTCOME MEASURE

Epidemiologic data, association of tinnitus with the otologic and systemic diseases.

RESULTS

The number of patients who received medical care because of tinnitus was 1.44% (0.78 million per 51 million) in 2015. There was a higher prevalence of tinnitus in women, and the overall prevalence increased with increasing age of patients and peaked at patients in their 70s (4.43%). The prevalence of tinnitus among patients aged 10 to 30 years, showed a tendency to increase during study period. In the regional analysis, highest prevalence was observed in Gwangju (2.02%). In comparison with the control group, the patients with tinnitus showed a higher frequency in otologic and systemic disease. Especially, noise induced hearing loss (adjusted odds ratio [AOR] = 82.1, 95% confidence interval [95% CI] = 74.8-90.2) and sudden sensorineueal hearing loss (AOR = 49.7, 95% CI = 48.4-51.0) showed high frequency in tinnitus patient group.

CONCLUSIONS

The prevalence and incidence of tinnitus in this study for entire nation were lower than previously reported studies. These results have limitation because the study only covered patient using the medical service for tinnitus and missed tinnitus sufferers not seeking medical service. However, this study is meaningful in that it was targeting entire nation, reflected the characteristics of clinically significant tinnitus patient enough to visit medical service.

Sudden sensorineural hearing loss with end-stage renal disease: a report of 32 cases

Background: Patients with end-stage renal disease (ESRD) have a higher risk of suffering sudden sensorineural hearing loss (SSNHL), but little is known about this population. Aims and objectives: To investigate the clinical characteristics, treatment and recovery of SSNHL patients with ESRD. Materials and methods: Records of 32 SSNHL patients with ESRD were reviewed, including clinical characteristics and hearing recovery. Patients were divided into intratympanic steroid (ITS) group and oral steroid (OS) group, and hearing recovery was compared between two groups. Results: Twenty-six patients (81.3%) exhibited tinnitus, and 18 patients (56.3%) suffered vertigo. Mean pure-tone threshold at the initial presentation was 73.2 ± 19.4 dB, and the audiogram configuration was ascending in 9.4%, descending in 9.4%, flat in 34.4% and profound in 46.9% cases. At 3-month follow-up, percentages of patients in complete recovery, partial recovery, slight recovery, and no improvement were 18.8%, 31.3%, 21.9% and 28.1%, respectively. Furthermore, the overall recovery rate, complete recovery rate and hearing improvement were significantly higher in the ITS group than those in the OS group. Conclusion: SSNHL patient with ESRD often suffered a severe hearing loss with a high rate of accompanying tinnitus and vertigo. ITS may provide better audiological results for SSNHL with ESRD than OS.

Risk of sudden sensorineural hearing loss in patients with dysrhythmia: A nationwide population-based cohort study

Objective

Whether dysrhythmia is a risk factor of sudden sensorineural hearing loss (SSNHL) remains unclear. In this study, we aimed to investigate the risk of developing SSNHL among patients with dysrhythmia in different age and gender groups by using population-based data in Taiwan.

Methods

We conducted a matched cohort study by analyzing data between January 2000 and December 2013 obtained from the Taiwan National Health Insurance Research Database. 41,842 newly diagnosed dysrhythmia patients and 83,684 comparison subjects without dysrhythmia were selected from claims. The incidence of sudden sensorineural hearing loss at the end of 2013 was determined in both groups. Univariate and multivariate logistic regression analyses were used to investigate the risk of SSNHL among patients with dysrhythmia.

Results

The incidence of SSNHL was 1.30-fold higher in the dysrhythmia group compared with the control group (53.2 versus 40.9 per 100,000 person-years), and using Cox proportional hazard regressions, the adjusted hazard ratio (HR) was 1.40 (95% confidence interval [CI], 1.15–1.70). Gender-stratified analysis revealed a significantly higher risk of SSNHL in patients with dysrhythmia than in those without dysrhythmia for both men and women (HR = 1.34, 95% CI = 1.02–1.76, P = 0.039, HR = 1.35, 95% CI = 1.02–1.78, P = 0.035, respectively). Age-stratified analysis revealed remarkable associations between dysrhythmia and SSNHL among those aged less than 40 years and more than 65 years (HR = 2.18, 95% CI = 1.03–4.64, P = 0.043 and HR = 1.54, 95% CI = 1.14–2.09, P = 0.006, respectively).

Conclusions

Our findings support dysrhythmia as an independent risk factor for SSNHL. Based on the study results, clinicians managing patients with dysrhythmia should be aware of the increased risk of developing SSNHL, especially among patients aged <40 and >65 years, and counsel patients to seek medical advice immediately if they experience any acute change in their hearing ability.

Increased incidence in hospitalised patients with sudden sensorineural hearing loss: a 14-year nationwide population-based study

Objective: To conduct a 14-year nationwide study on the epidemiologic incidence in patients with sudden sensorineural hearing loss (SSNHL). Design: Retrospective cross-sectional design. Study sample: Data of patients hospitalised with the diagnosis of SSNHL from 2000 to 2013, extracted from the Taiwan National Health Insurance Research Database. Results: In total, 31,258 patients were included. The mean age was 50.30 ± 16.70 years. Males (53.5%) were more commonly diagnosed with SSNHL than females (46.5%). The patients most commonly presented with SSNHL were in the age group of 45-64 years. The crude incidence of SSNHL from 2000 to 2013 was 9.76 per 100,000 people per year. The annual incidence rate shows a steady increased from 5.15 in 2000 to 13.97 per 100,000 people in 2013 with a statistical significance (p < 0.001). Conclusion: This 14-year nationwide study indicated an increased incidence rate of SSNHL. This necessitates the development of additional treatment modalities to enhance the prognosis and the clarification of the underlying mechanism of this enigmatic disease.

Idiopathic sudden sensorineural hearing loss in dialysis patients

Although sudden sensorineural hearing loss (SSNHL) affects chronic kidney disease (CKD) patients more frequently than non-CKD patients, few reports have described SSNHL in dialysis patients. We aimed to review the characteristics of SSNHL in chronic dialysis patients and evaluate treatment responses to steroid therapy. We retrospectively reviewed the records of dialysis patients diagnosed with idiopathic SSNHL at Asan Medical Center between January 2000 and December 2014. Pure tone and speech audiometry analyzes were performed before and 2 weeks and 2 months after treatment onset to evaluate outcomes. Twenty-two patients (11 men, 11 women; mean age: 49.9 ± 11.7 years) were included; 16 (72%) and 6 (28%) had undergone hemodialysis and peritoneal dialysis, respectively, for a median of 49.2 ± 41.4 (1–144) months. End-stage renal disease was most frequently caused by diabetic nephropathy (11 cases), chronic glomerulonephritis (1 case) and unknown factors (7 cases). Common accompanying symptoms included tinnitus (68.2%), ear fullness (45.5%) and vertigo (27.3%). The mean pure tone audiometry threshold at the initial presentation was 82.6 ± 22.4 dB. At 2 months post-steroid treatment, 4 (18.2%), 4 (18.2%) and 6 (27.3%) patients exhibited a complete, partial, or slight recovery, respectively; 8 patients (36.3%) showed no improvement. Although we could not identify the specific cause of SSNHL in this population, our relatively large case series elucidates the precise clinical features of SSNHL in this population and demonstrates the outcomes of steroid treatment.

Exocyst Complex Member EXOC5 Is Required for Survival of Hair Cells and Spiral Ganglion Neurons and Maintenance of Hearing

The exocyst, an octameric protein complex consisting of Exoc1 through Exoc8, was first determined to regulate exocytosis by targeting vesicles to the plasma membrane in yeast to mice. In addition to this fundamental role, the exocyst complex has been implicated in other cellular processes. In this study, we investigated the role of the exocyst in cochlear development and hearing by targeting EXOC5, a central exocyst component. Deleting Exoc5 in the otic epithelium with widely used Cre lines resulted in early lethality. Thus, we generated two different inner ear-specific Exoc5 knockout models by crossing Gfi1^Cre mice with Exoc5^f/f mice for hair cell-specific deletion (Gfi1^Cre/+;Exoc5^f/f) and by in utero delivery of rAAV-iCre into the otocyst of embryonic day 12.5 for deletion throughout the otic epithelium (rAAV2/1-iCre;Exoc5^f/f). Gfi1^Cre/+;Exoc5^f/f mice showed relatively normal hair cell morphology until postnatal day 20, after which hair cells underwent apoptosis accompanied by disorganization of stereociliary bundles, resulting in progressive hearing loss. rAAV2/1-iCre;Exoc5^f/f mice exhibited abnormal neurite morphology, followed by apoptotic degeneration of spiral ganglion neurons (SGNs) and hair cells, which led to profound and early-onset hearing loss. These results demonstrate that Exoc5 is essential for the normal development and survival of cochlear hair cells and SGNs, as well as the functional maintenance of hearing.

Nationwide epidemiological survey of idiopathic sudden sensorineural hearing loss in Japan

OBJECTIVES

Using a large-scale nationwide survey database, we investigated the epidemiological characteristics for idiopathic SSNHL in Japan.

METHODS

The subjects for this analysis were patients registered in a Japanese multicentre database between April 2014 and March 2016. A total of 3419 idiopathic SSNHL patients were registered in the database, and the clinical characteristics of the idiopathic SSNHL patients were obtained. Several factors associated with the severity of hearing impairment and prognosis were then investigated. Statistical analysis was performed to clarify the factors associated with the severity of hearing impairment and prognosis.

RESULTS

There were significant correlations between the severity of hearing loss and diabetes mellitus, kidney disease, past history of brain infarction, heart disease, age (under 16 years/elderly), and symptoms of vertigo/dizziness. We also analyzed the prognostic factors for idiopathic SSNHL, and found that the severity of hearing loss (Grade 3 or 4), heart disease, aged 65 years or over, time from onset to treatment (over 7 days), and symptoms of vertigo/dizziness were all significantly related to poor prognosis.

CONCLUSION

The present large-scale clinical survey revealed current epidemiological trends for idiopathic sudden sensorineural hearing loss (SSNHL) and various factors associated with the severity of hearing impairment and prognosis.

Sudden sensorineural hearing loss: Is there a connection with inner ear electrolytic disorders? A literature review

Electrolytic disorders of the inner ear represent a model that could be implicated in partially explaining the pathogenesis of sudden sensorineural hearing loss (SSNHL). Different types of electrolytes and different inner-ear loci are involved in cochlear homeostasis physiologically, to ensure the maintenance of an ion-balanced cochlear environment allowing a normal hair cell function. It has been hypothesized that a sudden loss of endocochlear potential, due to a rapid disruption of the inner ear fluid osmolality, could be responsible for a deterioration of the hearing function caused by damaged hair cells. The aim of this paper was to review the current literature and identify sources which might validate/fortify the hypothesis that inner ear electrolytic disorders have a role in the etiopathogenesis of SSNHL. The data in the literature underline the importance of ionic homeostasis in the inner ear, but they do not support a direct link between SSNHL and electrolyte disorders/imbalances. There is marginal evidence from otoacoustic emissions research that an indirect link might be present.

Increased risk of sudden sensorineural hearing loss in patients with depressive disorders: population-based cohort study

OBJECTIVES

To evaluate the incidence rates and risk of sudden sensorineural hearing loss among patients with depressive disorders.

METHOD

Data for 27 547 patients with newly diagnosed depressive disorders and 27 547 subjects without depressive disorders between 2001 and 2008 were yielded from the Taiwan National Health Insurance Research Database. Sudden sensorineural hearing loss incidence at the end of 2011 was determined. Cumulative incidence and adjusted hazard ratio were computed.

RESULTS

Sudden sensorineural hearing loss incidence was 1.45 times higher in the depressive disorders group compared to the non-depressive disorders group (p = 0.0041), with an adjusted hazard ratio of 1.460. A significant increased risk of developing sudden sensorineural hearing loss was noted in patients with diabetes mellitus, chronic kidney disease and hyperlipidaemia (p < 0.05).

CONCLUSION

The results suggest an increased risk of developing sudden sensorineural hearing loss in patients with depressive disorders. Co-morbidities such as diabetes mellitus, chronic kidney disease and hyperlipidaemia significantly aggravated the risk. Depressive disorders might be considered a risk factor for sudden sensorineural hearing loss. It remains to be seen whether control of depressive disorders can decrease the incidence of sudden sensorineural hearing loss in patients with depressive disorders.

Recurrence of idiopathic sudden sensorineural hearing loss: a retrospective cohort study

OBJECTIVE

To explore the recurrence rate of idiopathic sudden sensorineural hearing loss (ISSNHL).

DESIGN

Using the Taiwan Longitudinal Health Insurance Database, we compared in a retrospective cohort study 45,715 patients with ISSNHL between January 2001 and December 2006 with 45,715 age-, gender-, and comorbidity-matched controls without ISSNHL. We followed each patient from 180 days after the initial diagnosis until the end of 2009 and evaluated the incidence of ISSNHL for 3 years minimum.

RESULTS

The cumulative incidence of ISSNHL recurrence was 4.99%. Cox proportional hazard regressions showed that the 50- to 64-year-old age group had a higher adjusted hazard ratio (1.59; 95% confidence interval: 1.40-1.81) than did the 0- to 34-year-old age group. Different comorbidities did not significantly affect the incidence of ISSNHL relapse.

CONCLUSIONS

The risk of an ISSNHL relapse in patients with a history of ISSNHL was higher than was the risk of a first occurrence of ISSNHL in the Controls. We suggest that physicians counsel patients with a history of ISSNHL to seek medical attention if they have hearing impairments because they may also have a high risk of an ISSNHL relapse.

EVIDENCE LEVEL

2B.

Role of Obesity on the Prognosis of Sudden Sensorineural Hearing Loss in Adults

OBJECTIVE

To investigate the role of obesity/overweight on the prognosis of sudden sensorineural hearing loss (SSHL).

STUDY DESIGN

Retrospective cohort study.

SETTING

Outpatient department of a community hospital.

SUBJECTS AND METHODS

We collected 254 adult patients with SSHL from a community hospital. The odd ratios of body mass index (BMI) or obesity/overweight (BMI ≥25 kg/m(2)) on the recovery of SSHL were evaluated with multivariate logistic regression analysis.

RESULTS

There were 120 (47.2%) patients in the nonobesity group (BMI <25 kg/m(2)) and 134 (52.8%) patients in the obesity/overweight group (BMI ≥25 kg/m(2)). The complete and partial recovery rates were 10.0% and 49.2% in the nonobesity group and 9.7% and 47.0% in the obesity/overweight group, respectively. Univariate logistic regression showed that BMI had no significant association with recovery of SSHL (odds ratio [OR] of complete and partial recovery versus no recovery = 1.04, 95% confidence interval [CI] = 0.965-1.113, P = .327). Multivariate logistic regression analysis also showed that BMI (OR = 1.04, 95% CI = 0.964-1.131, P = .292) was not significantly associated with the recovery of SSHL for all subjects, after adjusting for all considered variables. Also, obesity/overweight (BMI ≥25 kg/m(2)) had no significant association with the recovery of SSHL.

CONCLUSION

Obesity/overweight would appear to have no significant effect on the prognosis of SSHL.

Effect of comorbid diabetes and hypercholesterolemia on the prognosis of idiopathic sudden sensorineural hearing loss

OBJECTIVES

We tested the hypothesis that comorbid diseases significantly affect the prognosis of sudden sensorineural hearing loss (ISSNHL).

STUDY DESIGN

A retrospective cohort study.

METHODS

The records of patients newly diagnosed with ISSNHL and treated with steroid prednisolone in a tertiary referral center between January 2003 and December 2013 were retrospectively reviewed. Pretreatment and posttreatment hearing levels were evaluated using pure-tone average (PTA) and word recognition score (WRS). The comorbidities of diabetes, hypertension, coronary artery disease, hypercholesterolemia, cerebrovascular disease, chronic kidney disease, and anemia were identified. We examined the effects of these comorbid diseases on the prognosis of ISSNHL 2 months posttreatment.

RESULTS

Regression analyses adjusted for gender, age, pretreatment hearing, treatment delay time, and all the comorbidities showed that the probability of major improvement in the PTA was significantly higher in patients without diabetes compared to those with diabetes (univariate odds ratio [OR], 1.90; 95% confidence interval (CI), 1.25-2.90; multivariate OR, 1.69; 95% CI, 1.03-2.77). Major (≥ 90%) and moderate (50%-89% improvement of the PTA, but with a remaining hearing loss of > 10 dB) improvement in the PTA was significantly higher in patients without hypercholesterolemia compared to those with hypercholesterolemia (univariate OR, 1.78; 95% CI, 1.13-2.80; multivariate OR, 1.70; 95% CI, 1.02-2.84). There was, however, no significant difference in the distribution of major (≥ 90%), moderate (50%-89%), and minor (< 50%) improvement in the posttreatment WRS for these comorbid diseases.

CONCLUSIONS

Comorbid diabetes or hypercholesterolemia may indicate a smaller probability of major or moderate PTA improvement for patients with ISSNHL.

Risk of sudden sensorineural hearing loss in patients with common preexisting sensorineural hearing impairment: a population-based study in Taiwan

Objective

The role of preexisting sensorineural hearing impairment on the risk for sudden sensorineural hearing loss (SSHL) is still unclear. In this study, we aimed to assess the risk of SSHL in patients with common preexisting sensorineural hearing impairment using population-based data.

Methods

A population-based case-control study design was used to analyze claims data between January 2001 and December 2011 obtained from the Taiwan National Health Insurance Research Database. The cases consisted of 514 patients with SSHL and the controls were frequency matched to 2,570 cases by sex, 10-year age group, and year of index date. Common sensorineural hearing impairments were retrospectively assessed in the cases and controls. Associations between sensorineural hearing impairment and risk of SSHL were evaluated using unconditional univariate and multivariate logistic regression analyses.

Results

The mean age for the 3,084 study subjects was 53.1 years (standard deviation, S.D. = 15.6). Of the 514 cases, 49 (9.5%) had sensorineural hearing impairment while only 44 (1.7%) of the 2,570 controls had the same condition. Univariate logistic regression analyses indicated that preexisting sensorineural hearing impairment was significantly associated with SSHL (odds ratio, OR = 6.05, p < 0.001). Other comorbidities including hypertension, diabetes mellitus, and hyperlipidemia also showed significant associations with SSHL. Similar results were obtained when the association between SSHL and sensorineural hearing impairment was adjusted with either all the covariates (adjusted OR = 6.22, p < 0.001) or with only those selected using a backward elimination procedure (adjusted OR = 6.20, p < 0.001).

Conclusions

Results from this population-based case-control study revealed that common sensorineural hearing impairment might be a novel risk factor for SSHL.

A retrospective case-control analysis of the outpatient expenditures for western medicine and dental treatment modalities in CKD patients in Taiwan

BACKGROUND

To determine if expenditures for dentistry (DENT) correlate with severity of chronic kidney disease (CKD).

METHODS

A total of 10,457 subjects were enrolled from January 2008 to December 2010, divided into three groups: healthy control (HC) group (n = 1,438), high risk (HR) group (n = 3,392), and CKD group (n = 5,627). Five stages were further categorized for the CKD group. OPD utilization and expenditures for western medicine (WM), DENT, and TCM (traditional Chinese medicine) were analyzed retrospectively (2000-2008) using Taiwan's National Health Insurance Research Database. Three major areas were analyzed among groups CKD, HR and HC in this study: 1) demographic data and medical history; 2) utilization (visits/person/year) and expenditures (9-year cumulative expenditure, expenditure/person/year) for OPD services in WM, DENT, and TCM; and 3) utilization and expenditures for dental OPD services, particularly in dental filling, root canal and periodontal therapy.

RESULTS

OPD utilization and expenditures of WM increased significantly for the CKD group compared with the HR and HC groups, and increased steadily along with the severity of CKD stages. However, overall DENT and TCM utilization and expenditures did not increase for the CKD group. In comparison among different CKD stages, the average expenditures and utilization for DENT including restorative filling and periodontal therapy, but not root canal therapy, showed significant decreases according to severity of CKD stage, indicating less DENT OPD utilization with progression of CKD.

CONCLUSIONS

Patients with advanced CKD used DENT OPD service less frequently. However, the connection between CKD and DENT service utilization requires further study.

Could the type of treatment for chronic kidney disease affect the auditory system?☆☆Please cite this article as: Lopez PS, Silva DPC, Martin LC, Montovani JC. Could the type of treatment for chronic Kidney disease affect the auditory system? Braz J Otorhinolaryngol. 2014;80:54-9

Introdução

Doença renal crônica (DRC) é definida pela presença de lesão renal levando à perda lenta e progressiva da função renal. A influência do tratamento da DRC sobre a audição ainda é inconclusiva.

Objetivo

Comparar testes auditivos entre pacientes com DRC submetidos a diferentes tipos de tratamento.

Material e método

Cohort transversal. Os grupos foram divididos de acordo com o tratamento: hemodiálise (n = 35), diálise peritoneal (n = 15), conservador (n = 51) e 27 pacientes saudáveis (controle). Pacientes com idade superior a 60 anos, perda auditiva congênita, síndromes genéticas, infecções de orelha média e transplante renal foram excluídos da pesquisa. A avaliação audiológica incluiu audiometria tonal, emissões otoacústicas evocadas transientes e Potencial Evocado Auditivo de Tronco Encefálico (PEATE); e as variáveis avaliadas foram: sexo, idade, diagnóstico de hipertensão arterial e diabetes, estadiamento da DRC, tempo de diagnóstico do diabetes e da hipertensão arterial, duração da DRC e do tratamento.

Resultados

A idade, presença de hipertensão arterial e tempo de DRC foram estatisticamente significantes e controlados. O grupo conservador apresentou piores limiares auditivos na audiometria tonal e o intervalo III-V do PEATE significativamente maior que o da hemodiálise.

Conclusão

O tratamento conservador mostrou piores resultados na avaliação auditiva, independente de diabetes e de hipertensão, reforçando que os pacientes submetidos a tratamento para DRC merecem avaliação auditiva completa para melhor compreensão da doença e de seus efeitos sobre o sistema auditivo.

Cause of idiopathic sudden sensorineural hearing loss: The stress response theory

The stress response theory is a relatively new concept about the cause of idiopathic sudden sensorineural hearing loss (ISHL). A number of possible etiologies have been proposed in the literature, as discussed in this paper, but each proposed etiology has been both supported and refuted in the literature. However, the stress response theory can integrate hypotheses that have been advocated so far. The word “stress” refers to a constellation of physical and psychological stimuli including systemic viral and bacterial illness, systemic inflammatory disorders, and physical, mental or metabolic stress. Numerous studies have demonstrated adverse effects of systemic stress on health. Stress causes changes in the immune system and cytokine network through activation of the hypothalamus-pituitary-adrenal axis and the sympathetic nervous system. Several types of catecholamine and cytokine receptors are in the cochlea cells other than capillary cells, and then they can respond to systemic stressors. However, there are few studies examining how systemic stress is associated with cochlear dysfunction. The stress response theory addresses this question. In the theory, a variety of stressors and risk factors contribute to the onset of ISHL in varying degrees. The lateral wall of the cochlea has very unique responses to systemic stressors. It plays a critical role in causing ISHL. Systemic stressors converge at the lateral wall and trigger pathological activation of nuclear factor κ-light-chain-enhancer of activated B cells, a transcriptional factor known as a stress sensor. This activation enhances local expression of genes associated with immune and inflammatory system, resulting in cochlear dysfunction. We review the original stress response theory advocated by Adams et al and the integrative stress response theory that integrates our knowledge about the etiologies of ISHL so far.