Sudden deafness: is it viral?

Association of ambient air pollution and Air Quality Index with risk of sudden sensorineural hearing loss: a cross-sectional study

OBJECTIVES

To explore the associations of air pollutants and Air Quality Index (AQI) with risk of sudden sensorineural hearing loss (SSNHL) DESIGN: Cross-sectional study SETTING: Medical record data and local population data collected between 2014 and 2022 in Changshu, China were retrospectively reviewed.

PARTICIPANTS

Adults aged 18 years and above who were diagnosed with SSNHL in Changshu No. 1 People's Hospital or Changshu No. 2 People's Hospital from the spring of 2014 to the fall of 2022 were included in the study.

OUTCOME MEASURE

SSNHL was diagnosed by clinicians using the Chinese diagnostic criteria for SSNHL.

RESULTS

Compared with those exposed to the lowest tertile of carbon monoxide (CO), the prevalence ratio for those exposed to middle and high tertiles of CO were 1.113 (95% CI 1.022 to 1.213) and 1.230 (95% CI 1.105 to 1.369), respectively. The risk of SSNHL was increased by 30.6% (95% CI 9.9% to 55.4%) per doubling increment of CO. No categorical association was found between ozone (O3) exposure and risk of SSNHL, however, an increased risk of 22.2% (0.8%-48.2%) was identified for each doubling of O3. No association was identified between other pollutants and AQI and risk of SSNHL.

CONCLUSIONS

In this study, CO and O3 were associated with an increased risk of SSNHL in Changshu, China. Further studies are warranted to confirm our findings.

Sudden sensorineural hearing loss: audiological profile during the COVID-19 pandemic

Introduction

Sudden sensorineural hearing loss (SSNHL) is an otological emergency that requires prompt recognition and intervention to prevent devastating impacts on people's lives. During the COVID-19 pandemic, sensory deprivations have been reported in patients positive for SARS-CoV-2 virus, including deleterious effects on the auditory pathway. This study aims to describe the audiological profile of individuals with SSNHL during the COVID-19 pandemic and to correlate hearing recovery in subgroups of individuals with or without COVID-19.

Methods

Prospective cohort including patients diagnosed with SSNHL evaluated in a tertiary care center between March 2020 and September 2022. Hearing loss was confirmed with pure-tone and speech audiometry, with Speech Recognition Threshold (SRT) and word recognition score (WRS). Audiometric testing was performed at the moment of diagnosis, then 7, 30 and 120 days after diagnosis. The average degree of hearing loss was assessed by calculating the 4-frequency pure tone average (4fPTA). The investigation of COVID-19 included RT-PCR technique for the SARS-CoV-2 virus and collection of information regarding disease severity. A statistical analysis was performed using an analysis of covariance (ANCOVA) model to compare the 4fPTA between the four groups (with and without a history of COVID-19, unilateral and bilateral cases) at the end of the follow-up period.

Results

Fifty-two patients with SSNHL were assessed, 40 (76.9%) with unilateral and 12 (23.1%) with bilateral hearing loss, totaling 64 ears included. Of those, 15 (28.8%) patients tested positive for SARS-CoV-2 and were symptomatic for COVID-19. Of all unilateral cases, 22.5% were seropositive and showed symptoms of COVID-19, a number that increased to 50% for bilateral cases. Comparing the COVID-19 positive groups, individuals with unilateral SSNHL went from 40 dB as their average 4fPTA at onset to 20 dB as their average 4fPTA after 120 days, whereas those with bilateral SSNHL went from an initial average of 60 dB to a final average of 66 dB. Although the 4fPTA value of individuals with unilateral SSNHL improved in 7 days, the mean values showed no significant difference between positive and negative groups. There was a higher incidence of bilateral simultaneous SSNHL in patients who had not been vaccinated against COVID-19 and who presented with symptoms of severe COVID-19.

Conclusion

Infection with SARS-CoV-2 resulted in more severe SSNHL, in bilateral SSNHL, and in poorer recovery from SSNHL in bilateral cases. Bilateral SSNHL was seen more frequently in patients who had not received vaccination against COVID-19.

Incidence of hearing loss following COVID-19 among young adults in South Korea: a nationwide cohort study

Background

The association of COVID-19 with hearing loss (HL) is unclear among young adults and needs to be investigated. This study was conducted to determine the association of COVID-19 with HL and sudden sensorineural hearing loss (SSNHL) in young adults.

Methods

This nationwide population-based cohort study used data from the Korea Disease Control and Prevention Agency-COVID-19-National Health Insurance Service. The study population consisted of young adult citizens aged 20-39 years without a history of HL. All participants were followed up from July 1, 2022 until HL, death, or December 31, 2022. A positive diagnosis of SARS-CoV-2 infection was determined through laboratory testing employing real-time reverse transcription polymerase chain reaction assays using nasopharyngeal or oropharyngeal swabs. The primary and secondary outcomes were HL and SSNHL, respectively. Age, sex, household income, Charlson comorbidity index, COVID-19 vaccination, hypertension, diabetes, and dyslipidemia-adjusted subdistribution hazard ratios (aSHRs) and 95% confidence intervals (CIs) were evaluated using the Fine-Gray subdistribution hazard regression model, considering overall death as a competing event to compare the aSHRs between COVID-19 positive and negative groups.

Findings

A total of 6,716,879 young adults were eligible for the analyses. During 40,260,757 person-months (PMs) of follow-up, 38,269 cases of HL and 5908 cases of SSNHL were identified. The risk of HL (incidence: 11.9 versus 3.4/10,000 PMs; SHR, 3.51; 95% CI, 3.39-3.63; aSHR, 3.44; 95% CI, 3.33-3.56; P < 0.0001) and SSNHL (incidence: 1.8 versus 0.5/10,000 PMs; SHR, 3.58; 95% CI, 3.29-3.90; aSHR, 3.52; 95% CI, 3.23-3.83; P < 0.0001) was higher in COVID-19 group as compared to no COVID-19 group. In the sensitivity analyses that evaluated HL and SSNHL risks after adopting multiple imputations, utilizing inverse probability of treatment weighting, limiting study population to the cohort with a health screening examination, the results were consistent to the primary analysis.

Interpretation

Our findings suggest a heightened risk of HL and SSNHL following COVID-19 in young adults. Due to study limitations, including the lack of objective audiological data, issues with generalizability to other populations, and the retrospective design, careful interpretation is necessary. Further studies with objective audiological data and a longer follow-up period are warranted.

Funding

IITP (Institute for Information & Communications Technology Planning & Evaluation; IITP-2024- RS-00156439) and Jeju National University Hospital Research Fund (2023).

Idiopathic sudden sensorineural hearing loss after COVID-19 vaccination: a systematic review and meta-analysis

OBJECTIVE

To provide pooled analyses on the association between COVID-19 vaccine and the incidence of idiopathic sudden sensorineural hearing loss (ISSNHL).

DATA SOURCES

"Medline" via "PubMed", "EMBASE", and "Google scholar".

REVIEW METHODS

Data sources were inspected from January 2020 to January 2024 using search terms relevant to vaccines for COVID-19. Included were papers with reported numbers of vaccinated populations and incidence if ISSNHL in those populations. Quality assessment was performed with the Newcastle-Ottawa Quality Assessment Scale Criteria.

RESULTS

Three publications encompassing more than 191.8 million patients and at least 283 million vaccine doses were included in the quantitative data synthesis. The pooled reported incidence (95%confidence interval) of ISSNHL among COVID-19 vaccine recipients was 1.2588 per 100,000 (0.1385-3.4836). This incidence is significantly lower than the incidence of 5-27 and 60 per 100,000/year reported in the United States and in the European Union, respectively (P < 0.0001).

CONCLUSION

There is no evidence to indicate that the COVID-19 vaccine is associated with the incidence of ISSNHL.

Association of sudden sensorineural hearing loss with meteorological factors: a time series study in Hefei, China, and a literature review

Air pollution can cause disease and has become a major global environmental problem. It is currently believed that air pollution may be related to the progression of SSNHL. As a rapidly developing city in recent years, Hefei has serious air pollution. In order to explore the correlation between meteorological variables and SSNHL admissions, we conducted this study. This study investigated the short-term associations between SSNHL patients admitted to the hospital and Hefei climatic variables. The daily data on SSNHL-related hospital admissions and meteorological variables containing mean temperature (T-mean; °C), diurnal temperature range (DTR; °C), atmospheric pressure (AP; Hp), and relative humidity (RH; %), from 2014 to 2021 (2558 days), were collected. A time-series analysis integrating distributed lag non-linear models and generalized linear models was used. PubMed, Embase, Cochrane Library, and Web of Science databases were searched. Literature published up to August 2023 was reviewed to explore the potential impact mechanisms of meteorological factors on SSNHL. The mechanisms were determined in detail, focusing on wind speed, air pressure, temperature, humidity, and air pollutants. Using a median of 50.00% as a baseline, the effect of exceedingly low T-mean in the single-day hysteresis effect model began at a lag of 8 days (RR = 1.032, 95% CI: 1.001 ~ 1.064). High DTR affected the admission rate for SSNHL on lag 0 day. The significance of the effect was the greatest on that day (RR = 1.054, 95% CI: 1.007 ~ 1.104) and then gradually decreased. High and exceedingly high RH affected the admission rate SSNHL on lag 0 day, and these effects lasted for 8 and 7 days, respectively. There were significant associations between all grades of AP and SSNHL. This is the first study to assess the effect of meteorological variables on SSNHL-related admissions in China using a time-series approach. Long-term exposures to high DTR, RH values, low T-mean values, and all AP grades enhance the incidence of SSNHL in residents. Limiting exposure to extremes of ambient temperature and humidity may reduce the number of SSNHL-related hospital visits in the region. It is advisable to maintain a suitable living environment temperature and avoid extreme temperature fluctuations and high humidity. During periods of high air pollution, it is recommended to stay indoors and refrain from outdoor exercise.

Signaling pathways regulating the immune function of cochlear supporting cells and their involvement in cochlear pathophysiology

The inner ear, including the cochlea, used to be regarded as an immune-privileged site because of its immunologically isolated environment caused by the blood-labyrinthine barrier. Cochlear resident macrophages, which originate from the yolk sac or fetal liver during the embryonic stage and are maintained after birth, are distributed throughout various regions of the cochlear duct. Intriguingly, these cells are absent in the organ of Corti, where hair cells (HCs) and supporting cells (SCs) are located, except for a limited number of ionized calcium-binding adapter molecule 1 (Iba1)-positive cells. Instead, SCs exert glial functions varying from a quiescent to an emergency state. Notably, SCs acquire the nature of macrophages and begin to secrete inflammatory cytokines during viral infection in the organ of Corti, which is ostensibly unprotected owing to the lack of general resident macrophages. This review provides an overview of both positive and negative functions of SCs enabled to acquire macrophage phenotypes upon viral infection focusing on the signaling pathways that regulate these functions. The former function protects HCs from viral infection by inducting type I interferons, and the latter function induces HC death by necroptosis, leading to sensorineural hearing loss. Thus, SCs play contradictory roles as immune cells with acquired macrophage phenotypes; thereby, they are favorable and unfavorable to HCs, which play a pivotal role in hearing function.

Association of Autonomic Symptom Burden with Sudden Sensorineural Hearing Loss

OBJECTIVE

To investigate the autonomic symptom burden in patients with sudden sensorineural hearing loss (SSNHL) and its association with the severity and prognosis.

STUDY DESIGN

Observational prospective study.

SETTING

Tertiary academic medical center.

METHODS

Patients diagnosed with SSNHL at a single medical center completed the COMPASS 31 questionnaire, which assesses dysautonomia across 6 domains with 31 questions. A total COMPASS 31 score was calculated by summing the scores from each weighted domain. The treatment outcome was evaluated by the percentage of recovery, calculated as the hearing gain in pure tone average (PTA) after treatment divided by the pretreatment PTA difference between the 2 ears. We defined poor recovery as a percentage of recovery <80%.

RESULTS

A total of 63 SSNHL patients were included. The mean COMPASS 31 score was 23.4 (SD 14). Patients with poor recovery had significantly higher COMPASS 31 scores than those with good recovery (mean 26.4 [SD 14.4] vs 16.9 [SD 10.4]; 95% confidence interval [CI] 2-17). There was a negative association between COMPASS 31 score and both hearing gain (r = -.323, 95% CI -0.082 to -0.529) and percentage of recovery (r = -.365, 95% CI -0.129 to -0.562). Multivariate analyses of independent factors indicate that patients with higher COMPASS 31 scores had a greater risk for poor recovery (OR 1.06 [95% CI 1.003-1.117]).

CONCLUSION

This study highlights the association between autonomic symptom burden and poor hearing outcomes in SSNHL patients. The findings underscore the importance of evaluating autonomic function during the treatment of SSNHL.

Approach to Sudden Hearing Loss Among Primary Care Physicians in Riyadh, Saudi Arabia

INTRODUCTION

A medical emergency known as sudden sensorineural hearing loss (SSNHL) affects the ears suddenly, has a considerable probability of negative cognitive and functional outcomes, and can influence the patient's quality of life. Primary care physicians play a crucial role in diagnosing SSNHL and initiating prompt and efficient management since they are the ones who would likely encounter it initially. This study aims to evaluate the present knowledge, diagnostic, and management perspective of SSNHL among primary care physicians in Riyadh, Saudi Arabia.

METHODS

A self-generated questionnaire with 17 questions was developed, and a link to the online survey was delivered to primary care physicians (PHPs) in Riyadh, Saudi Arabia, concerning the management of SSNHL.

RESULTS

The knowledge level regarding SSNHL was evaluated, in which 21 (25%) of the participants had a low knowledge level, 34 (40.5%) had moderate knowledge, and 29 (34.5%) had a high knowledge level. Among 84 participants, 20 (23.8%) were confident in their ability to administer and understand the findings of tuning fork tests (TFT) to differentiate between sensorineural hearing loss and conductive hearing loss, whereas 64 (76.2%) were unsure about it. In addition, to distinguish between sensorineural hearing loss and conductive hearing loss, 62 (73.8%) participants were confident, and 22 (26.2%) participants were skeptical about their ability to interpret a formal audiogram.

CONCLUSION

Considering SSNHL as a medical emergency, in our survey, many family doctors would make proper referral and treatment decisions. However, TFTs were underutilized for guiding management decisions compared to other ways to distinguish between conductive and sensorineural hearing loss.

Cochlear Implantation in Patients with Bilateral Sudden Sensorineural Hearing Loss after COVID-19 Infection

COVID-19 infection is associated with a variety of neurological manifestations. Since the inner ear is vulnerable to viruses, sensorineural hearing loss (SNHL) has been reported to occur following SARS-CoV-2 infection. We present here two cases of profound SNHL following SARS-CoV-2 infection. Pure-tone audiograms confirmed profound SNHL. The tympanogram and Auditory Brainstem Responses showed no abnormal symptoms. MRIs and CTs identified some changes but no significant anatomical nor physiological manifestations explaining the obvious cause for hearing loss. High doses of oral corticosteroids with additional conservative therapy were given with no therapeutic response, and therefore, cochlear implant surgery was performed. One case was bilaterally treated, and the other one received an implantation on one side. Both surgeries were carried out without intra- nor postoperative complications. Interestingly, in both cases, advanced fibrotic tissue was found during surgery. Both cases reported successful rehabilitation and are satisfied with their new sound perception following cochlear implantation.

High Cardio-Ankle Vascular Index Values in Idiopathic Sudden Sensorineural Hearing Loss Patients Indicate Better Prognosis

OBJECTIVE

Vascular disorders and viral infections are the presumed etiologies of idiopathic sudden sensorineural hearing loss (ISSNHL) and acute sensorineural hearing loss, with no identifiable cause. However, no clinical test for estimating the extent of vascular involvement in ISSNHL has been reported despite its potential impact on prognosis and treatment. We investigated the correlation between the cardio-ankle vascular index (CAVI), which reflects arterial stiffness and elasticity, and hearing improvement to ascertain its usefulness as an additional indicator of ISSNHL prognosis and etiology.

METHODS

We enrolled 182 patients diagnosed with definite ISSNHL. The percentage of mild ISSNHL patients and that of patients experiencing no change were compared between the high-CAVI and low-CAVI groups. Age, initial and final pure-tone average (PTA) values, CAVI, presence or absence of vertigo, and medical histories were retrospectively reviewed and included in univariate and multivariate analyses.

RESULTS

The percentage of mild ISSNHL patients was smaller in the high-CAVI group than in the low-CAVI group, whereas the percentage of patients experiencing no change was smaller in the high-CAVI group than in the low-CAVI group, although patients in the high-CAVI group were significantly older than those in the low-CAVI group. The Cox proportional hazard model revealed that high CAVI, hypertension, younger age, and initial PTA <90 dB were associated with hearing improvement.

CONCLUSIONS

ISSNHL in patients with high CAVI was more severe but had a better prognosis than that in those with low CAVI. CAVI may help evaluate diseases of vascular and other etiologies, as well as ISSNHL.

Prognostic Correlation of Immune-Inflammatory Markers in Sudden Sensorineural Hearing Loss: A Retrospective Study

BACKGROUND

The mechanism of sudden sensorineural hearing loss (SSNHL) remains incompletely understood, but immune cell infiltration has been identified as a crucial component in the sickness. The patients with SSNHL may benefit from investigating markers related to inflammation.

METHODS

From April 2022 to 2023, 80 patients who were diagnosed with SSNHL in the Department of Otolaryngology at Yangzhou University's Clinical Medical College were enrolled in the SSNHL group. And patients were separated into effective and ineffective groups based on the degree to which their hearing had recovered prior to discharge. As the control group, 80 healthy volunteers were chosen from hospital's physical examination center. Neutrophils, lymphocytes, platelets, and white blood cells were counted. Additionally, quantified and statistically examined were the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune inflammation index (SII). The risk variables for prognosis were identified using logistic regression models, and the prediction accuracy of the model was calculated using the receiver operating characteristic (ROC) curves.

RESULTS

The SSNHL group had higher levels of white blood cells, neutrophils, platelets, NLR, PLR, and SII than the control group. While the PLR lacked statistical significance, the NLR and SII of the patients in the ineffective group were noticeably higher than those in the effective group.

CONCLUSION

Patients with SSNHL exhibit inflammatory immune responses. Patients with SSNHL can have their prognosis determined by the simple peripheral blood indicators NLR and SII, particularly SII, which is significant for predicting prognosis and directing treatment.

Reassessment of oxidative stress in idiopathic sudden hearing loss and preliminary exploration of the effect of physiological concentration of melatonin on prognosis

Background and purpose

The pathogenesis of idiopathic sudden sensorineural hearing loss (ISSNHL) is still unclear, and there is no targeted treatment. This research aimed to verify the role of oxidative stress in ISSNHL and explore whether melatonin has a protective effect on hearing.

Materials and methods

A total of 43 patients with ISSNHL and 15 healthy controls were recruited to detect the level of melatonin, reactive oxygen species (ROS), and total antioxidant capacity (TAC) in the blood and compared before and after treatment. Multivariate logistic regression models were performed to assess the factors relevant to the occurrence and improvement of ISSNHL.

Results

The patients with ISSNHL showed significantly higher ROS levels than controls (4.42 ± 4.40 vs. 2.30 ± 0.59; p = 0.031). The levels of basal melatonin were higher (1400.83 ± 784.89 vs. 1095.97 ± 689.08; p = 0.046) and ROS levels were lower (3.05 ± 1.81 vs. 5.62 ± 5.56; p = 0.042) in the effective group as compared with the ineffective group. Logistic regression analysis showed that melatonin (OR = 0.999, 95% CI 0.997-1.000, p = 0.049), ROS (OR = 1.154, 95% CI 1.025-2.236, p = 0.037), and vertigo (OR = 3.011, 95% CI 1.339-26.983, p = 0.019) were independent factors associated with hearing improvement. Besides, the level of melatonin (OR = 0.999, 95% CI 0.998-1.000, p = 0.023) and ROS (OR = 3.248, 95% CI 1.109-9.516, p = 0.032) were associated with the occurrence of ISSNHL.

Conclusion

Our findings may suggest oxidative stress involvement in ISSNHL etiopathogenesis. The level of melatonin and ROS, and vertigo appear to be predictive of the effectiveness of hearing improvement following ISSNHL treatment.

Effect of Herpes Zoster Treatment and Sudden Sensorineural Hearing Loss Using National Health Insurance Claims Data of South Korea

Background and objectives: Herpes zoster (HZ) is caused by the reactivation of a pre-existing latent varicella zoster virus, which is one of the viruses that causes hearing loss, and hearing loss may occur due to a systemic immune response even if it does not invade the auditory nerve. This study aimed to determine the correlation between sudden sensorineural hearing loss (SSNHL) in older adult patients who received HZ treatment. Materials and Methods: We used the cohort data of patients aged 60 years and above (n = 624,646) between 2002 and 2015 provided by the National Health Insurance Service. The patients were divided into two groups: those who were diagnosed with HZ between 2003 and 2008 (group H, n = 36,121) and those who had not been diagnosed with HZ between 2002 and 2015 (group C, n = 584,329). Results: In the main model (adjusted HR = 0.890, 95% CI = 0.839-0.944, p < 0.001) adjusted for sex, age, and income, and the full model (adjusted HR = 0.894, 95% CI = 0.843-0.949, p < 0.001) adjusted for all comorbidities, group H had a lower risk of SSNHL than group C. Conclusions: This study showed that patients who received HZ treatment had a lower incidence of SSNHL within five years after diagnosis.

Repurposable Drugs That Interact with Steroid Responsive Gene Targets for Inner Ear Disease

Corticosteroids, oral or transtympanic, remain the mainstay for inner ear diseases characterized by hearing fluctuation or sudden changes in hearing, including sudden sensorineural hearing loss (SSNHL), Meniere's disease (MD), and autoimmune inner ear disease (AIED). Despite their use across these diseases, the rate of complete recovery remains low, and results across the literature demonstrates significant heterogeneity with respect to the effect of corticosteroids, suggesting a need to identify more efficacious treatment options. Previously, our group has cross-referenced steroid-responsive genes in the cochlea with published single-cell and single-nucleus transcriptome datasets to demonstrate that steroid-responsive differentially regulated genes are expressed in spiral ganglion neurons (SGN) and stria vascularis (SV) cell types. These differentially regulated genes represent potential druggable gene targets. We utilized multiple gene target databases (DrugBank, Pharos, and LINCS) to identify orally administered, FDA approved medications that potentially target these genes. We identified 42 candidate drugs that have been shown to interact with these genes, with an emphasis on safety profile, and tolerability. This study utilizes multiple databases to identify drugs that can target a number of druggable genes in otologic disorders that are commonly treated with steroids, providing a basis for establishing novel repurposing treatment trials.

Correlation of Neutrophil-to-Lymphocyte Ratio and the Dilation of the Basilar Artery with the Potential Role of Vascular Compromise in the Pathophysiology of Idiopathic Sudden Sensorineural Hearing Loss

Idiopathic sudden sensorineural hearing loss (SSNHL) currently lacks a clear etiology, as well as an effective treatment. One of the most probable explanations for SSNHL is impairment of the cochlear blood flow. However, dissimilar to a fundoscopic examination, direct observation of cochlear blood vessels is not possible. To indirectly support an ischemic etiology of SSNHL, we investigated whether the degree of initial hearing loss is associated with two atherosclerotic risk factors: dilatation of the basilar artery (BA) and a chronic subclinical inflammatory status measured by the neutrophil-to-lymphocyte ratio (NLR). This retrospective study collected data from 105 consecutive patients diagnosed with idiopathic SSNHL. Then, the patients were divided into two groups according to their NLR as “abnormally high NLR (>3.53, n = 22)” and “NLR within the normal range (0.78−3.53, n = 83)”. The BA diameter and severity of initial hearing loss were significantly correlated with each other in the abnormally high NLR group (p < 0.001). However, there was no significant correlation between initial hearing loss and the BA diameter in the normal NLR group (p = 0.299). Therefore, the NLR may serve as a marker for SSNHL of vascular etiology and a rationale for magnetic resonance imaging examinations based on the pathophysiology.

Sudden Sensorineural Hearing Loss: A Review

The objective of this review is to present and evaluate the current views on sudden sensorineural hearing loss. Sudden sensorineural hearing loss is an otolaryngology emergency requiring immediate diagnosis and treatment. The etiology of the majority of cases is unknown. The etiology can be classified into various categories such as autoimmune diseases, infections, functional, metabolic disorders, vascular disorders, traumatic causes, due to toxins, and neurological disorders. We searched the U.S. National Library of Medicine's PubMed database using the terms "sudden S.N.H.L.," "virus and ssnhl," and "sudden deafness," as well as the keywords such as "etiology," "COVID 19, and ssnhl," “epidemiology,” “clinical characteristics,” “management,” “therapy,” and “prognosis."

Idiopathic sudden sensorineural hearing loss: A critique on corticosteroid therapy

Idiopathic sudden sensorineural hearing loss (ISSNHL) is a condition affecting 5-30 per 100,000 individuals with the potential to significantly reduce one's quality of life. The true incidence of this condition is not known because it often goes undiagnosed and/or recovers within a few days. ISSNHL is defined as a ≥30 dB loss of hearing over 3 consecutive audiometric octaves within 3 days with no known cause. The disorder is typically unilateral and most of the cases spontaneously recover to functional hearing within 30 days. High frequency losses, ageing, and vertigo are associated with a poorer prognosis. Multiple causes of ISSNHL have been postulated and the most common are vascular obstruction, viral infection, or labyrinthine membrane breaks. Corticosteroids are the standard treatment option but this practice is not without opposition. Post mortem analyses of temporal bones of ISSNHL cases have been inconclusive. This report analyzed ISSNHL studies administering corticosteroids that met strict inclusion criteria and identified a number of methodologic shortcomings that compromise the interpretation of results. We discuss the issues and conclude that the data do not support present treatment practices. The current status on ISSNHL calls for a multi-institutional, randomized, double-blind trial with validated outcome measures to provide science-based treatment guidance.

A 14-year nationwide epidemiological analysis of delayed endolymphatic hydrops in Japan

BACKGROUND

Delayed endolymphatic hydrops (DEH) is an inner ear disease that causes recurrent vertigo in the ipsilateral ear or fluctuating hearing in the contralateral ear due to endolymphatic hydrops secondary to preceding deafness. There are few reports of large, multicentre studies investigating the clinical-epidemiological characteristics of DEH.

OBJECTIVE

This study aimed to clarify the characteristics of DEH in Japan.

METHODS

Clinical data on 662 patients with DEH were analysed by nationwide, multicentre surveys conducted by the Peripheral Vestibular Disorders Research Group of Japan.

RESULTS

The proportion of ipsilateral DEH (IDEH) was slightly higher than that of contralateral DEH (CDEH) at 55.4%. The time delay between onset of precedent deafness and onset of DEH was significantly longer for CDEH than for IDEH. The most common cause of precedent deafness was a disease of unknown cause with onset in early childhood (33.1%). Epidemiological characteristics were not significantly different between CDEH with and without vertigo.

CONCLUSION

DEH appearing to be caused by viral labyrinthitis has a high rate of onset within 40 years of precedent deafness. Clinical and epidemiological characteristics of IDEH, CDEH with vertigo, and CDEH without vertigo were very similar.

SIGNIFICANCE

The clinical-epidemiological characteristics of DEH in Japan were clarified.

Intratympanic corticosteroids for sudden sensorineural hearing loss

BACKGROUND

Idiopathic sudden sensorineural hearing loss (ISSNHL) is common, and defined as a sudden decrease in sensorineural hearing sensitivity of unknown aetiology. Systemic corticosteroids are widely used, however their value remains unclear. Intratympanic injections of corticosteroids have become increasingly common in the treatment of ISSNHL.

OBJECTIVES

To assess the effects of intratympanic corticosteroids in people with ISSNHL.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Trials Register; CENTRAL (2021, Issue 9); PubMed; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials (search date 23 September 2021).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) involving people with ISSNHL and follow-up of over a week. Intratympanic corticosteroids were given as primary or secondary treatment (after failure of systemic therapy).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods, including GRADE to assess the certainty of the evidence. Our primary outcome was change in hearing threshold with pure tone audiometry. Secondary outcomes included the proportion of people whose hearing improved, final hearing threshold, speech audiometry, frequency-specific hearing changes and adverse effects.

MAIN RESULTS

We included 30 studies, comprising 2133 analysed participants. Some studies had more than two treatment arms and were therefore relevant to several comparisons. Studies investigated intratympanic corticosteroids as either primary (initial) therapy or secondary (rescue) therapy after failure of initial treatment. 1. Intratympanic corticosteroids versus systemic corticosteroids as primary therapy We identified 16 studies (1108 participants). Intratympanic therapy may result in little to no improvement in the change in hearing threshold (mean difference (MD) -5.93 dB better, 95% confidence interval (CI) -7.61 to -4.26; 10 studies; 701 participants; low-certainty). We found little to no difference in the proportion of participants whose hearing was improved (risk ratio (RR) 1.04, 95% CI 0.97 to 1.12; 14 studies; 972 participants; moderate-certainty). Intratympanic therapy may result in little to no difference in the final hearing threshold (MD -3.31 dB, 95% CI -6.16 to -0.47; 7 studies; 516 participants; low-certainty). Intratympanic therapy may increase the number of people who experience vertigo or dizziness (RR 2.53, 95% CI 1.41 to 4.54; 1 study; 250 participants; low-certainty) and probably increases the number of people with ear pain (RR 15.68, 95% CI 6.22 to 39.49; 2 studies; 289 participants; moderate-certainty). It also resulted in persistent tympanic membrane perforation (range 0% to 3.9%; 3 studies; 359 participants; very low-certainty), vertigo/dizziness at the time of injection (1% to 21%, 3 studies; 197 participants; very low-certainty) and ear pain at the time of injection (10.5% to 27.1%; 2 studies; 289 participants; low-certainty). 2. Intratympanic plus systemic corticosteroids (combined therapy) versus systemic corticosteroids alone as primary therapy We identified 10 studies (788 participants). Combined therapy may have a small effect on the change in hearing threshold (MD -8.55 dB better, 95% CI -12.48 to -4.61; 6 studies; 435 participants; low-certainty). The evidence is very uncertain as to whether combined therapy changes the proportion of participants whose hearing is improved (RR 1.27, 95% CI 1.15 to 1.41; 10 studies; 788 participants; very low-certainty). Combined therapy may result in slightly lower (more favourable) final hearing thresholds but the evidence is very uncertain, and it is not clear whether the change would be important to patients (MD -9.11 dB, 95% CI -16.56 to -1.67; 3 studies; 194 participants; very low-certainty). Some adverse effects only occurred in those who received combined therapy. These included persistent tympanic membrane perforation (range 0% to 5.5%; 5 studies; 474 participants; very low-certainty), vertigo or dizziness at the time of injection (range 0% to 8.1%; 4 studies; 341 participants; very low-certainty) and ear pain at the time of injection (13.5%; 1 study; 73 participants; very low-certainty).  3. Intratympanic corticosteroids versus no treatment or placebo as secondary therapy We identified seven studies (279 participants). Intratympanic therapy may have a small effect on the change in hearing threshold (MD -9.07 dB better, 95% CI -11.47 to -6.66; 7 studies; 280 participants; low-certainty). Intratympanic therapy may result in a much higher proportion of participants whose hearing is improved (RR 5.55, 95% CI 2.89 to 10.68; 6 studies; 232 participants; low-certainty). Intratympanic therapy may result in lower (more favourable) final hearing thresholds (MD -11.09 dB, 95% CI -17.46 to -4.72; 5 studies; 203 participants; low-certainty). Some adverse effects only occurred in those who received intratympanic injection. These included persistent tympanic membrane perforation (range 0% to 4.2%; 5 studies; 185 participants; very low-certainty), vertigo or dizziness at the time of injection (range 6.7% to 33%; 3 studies; 128 participants; very low-certainty) and ear pain at the time of injection (0%; 1 study; 44 participants; very low-certainty).  4. Intratympanic plus systemic corticosteroids (combined therapy) versus systemic corticosteroids alone as secondary therapy We identified one study with 76 participants. Change in hearing threshold was not reported. Combined therapy may result in a higher proportion with hearing improvement, but the evidence is very uncertain (RR 2.24, 95% CI 1.10 to 4.55; very low-certainty). Adverse effects were poorly reported with only data for persistent tympanic membrane perforation (rate 8.1%, very low-certainty).

AUTHORS' CONCLUSIONS

Most of the evidence in this review is low- or very low-certainty, therefore it is likely that further studies may change our conclusions.   For primary therapy, intratympanic corticosteroids may have little or no effect compared with systemic corticosteroids. There may be a slight benefit from combined treatment when compared with systemic treatment alone, but the evidence is uncertain. For secondary therapy, there is low-certainty evidence that intratympanic corticosteroids, when compared to no treatment or placebo, may result in a much higher proportion of participants whose hearing is improved, but may only have a small effect on the change in hearing threshold. It is very uncertain whether there is additional benefit from combined treatment over systemic steroids alone. Although adverse effects were poorly reported, the different risk profiles of intratympanic treatment (including tympanic membrane perforation, pain and dizziness/vertigo) and systemic treatment (for example, blood glucose problems) should be considered when selecting appropriate treatment.

The Otoprotective Effect of Ear Cryotherapy: Systematic Review and Future Perspectives

This systematic review investigates ear cooling and cryotherapy in the prevention and treatment of inner ear damage and disease, within the context of animal models and clinical studies. A literature search was carried out in the databases Pubmed and Cochrane Library. Ten studies were identified concerning the otoprotective properties of cryotherapy. Nine of these were rodent in vivo studies (mice, rats, gerbils, guinea pigs). One study involved human subjects and investigated cryotherapy in idiopathic sensorineural hearing loss. The studies were heterogeneous in their goals, methods, and the models used. Disorder models included ischemia and noise damage, ototoxicity (cisplatin and aminoglycoside), and CI-electrode insertion. All ten studies demonstrated significant cryotherapeutic otoprotection for their respective endpoints. No study revealed or expressly investigated otodestructive effects. While limited in number, all of the studies within the scope of the review demonstrated some degree of cryotherapeutic, otoprotective effect. These promising results support the conducting of further work to explore and refine the clinical applicability and impact of cryotherpeutics in otolaryngology.

Efficacy of steroid treatment for sudden sensorineural hearing loss in patients with vestibular schwannoma

BACKGROUND

Sudden sensorineural hearing loss (SSNHL) has several aetiologies and may be a presenting symptom of vestibular schwannoma (VS).

OBJECTIVES

The aim of this study was to investigate the recovery rate after steroid treatment and the prognostic factors of SSNHL with VS.

MATERIALS AND METHODS

This was a retrospective observational study wherein 32 patients with VS who presented with SSNHL were analysed at a tertiary referral centre. Hearing gain and prognostic factors were the main outcome measures for steroid treatment intervention.

RESULTS

Among the 1698 patients presenting with SSNHL, VS was found in 43 (2.5%) patients. Eleven cases (34.3%) showed good recovery, with significant improvements in the pure-tone audiometry values. Even though age was a significant factor, there were no associations between steroid response and initial hearing level, presence of vertigo, tumour size, and tumour extension.

CONCLUSIONS AND SIGNIFICANCE

Our study showed that hearing recovery of SSNHL does not exclude a VS diagnosis. We suggest that steroid treatment be considered in patients with VS presenting SSNHL.

Association between human papillomavirus infection and sudden sensorineural hearing loss: A nationwide population-based cohort study

BACKGROUND

While the etiology of sudden sensorineural hearing loss (SSNHL) remains unclear, viral infection has been suggested as a possible cause. Human papillomavirus (HPV) might trigger immune-mediated reaction and induce inflammatory cytokines which are injurious to the cochlea. This study aimed to investigate the association between HPV infection and the risk of developing SSNHL using a nationwide population-based data set.

METHODS

In this study, we used the population-based National Health Insurance Research Database of Taiwan to enroll 49,247 individuals with HPV infection from January 1st, 2000, to December 31st, 2013, and compared with a control group of 98,494 individuals who had never been diagnosed with HPV infection (at a 1:2 ratio matched by age, sex, index year, and comorbidities) in relation to the risk of subsequent SSNHL. The primary outcome was the time from the index date to the date when the first diagnosis of SSNHL occurred, death, withdrawal from the National Health Insurance Program, or the end of the study. Cox model with frailty was conducted to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), relative to comparison group. Sensitivity analyses were performed to validate our findings.

FINDINGS

The adjusted hazard ratio (aHR) of developing SSNHL was 1.37 (95% CI, 1.07-1.74) after adjustment for demographic characteristics, comorbidities, and medications. Sensitivity analyses showed consistent positive association. In our sub-group analysis, a significantly higher effect of HPV on SSNHL was noted in the patients with a previous diagnosis of cerebrovascular disease, compared with those without cerebrovascular disease (aHR: 4.59 versus 1.27, p-value for interaction = 0.024).

INTERPRETATION

HPV infections are associated with higher risk of subsequent SSNHL in the Taiwanese population. More research is needed to examine the causality and to determine the potential efficacy of specific precautions.

FUNDING

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Effects of alprostadil combined with hyperbaric oxygen on hearing recovery and hemorheology in patients with sudden sensorineural hearing loss and analysis of related influencing factors

The causes of sudden sensorineural hearing loss (SSNHL) are unclear, and the condition cannot be treated with specific regimens. The present study was designed to explore the effects of alprostadil combined with hyperbaric oxygen (HBO) on hearing recovery and hemorheology in patients with SSNHL, and to analyze factors influencing treatment efficacy. in total, 104 patients with SSNHL were enrolled between January 2015 and July 2018 in a randomized controlled trial. Group A (n=52) received alprostadil treatment and Group B (n=52) were treated with HBO plus alprostadil. Following treatment, the overall recovery rates of tinnitus, aural fullness and vertigo in Group B were significantly higher than those in Group A (P<0.05). Low-, middle- and high-shear whole blood viscosity and whole blood viscosity in the two groups significantly decreased, and those in Group B were significantly lower than those in Group A (P<0.05). The present results indicated that the combination of alprostadil with HBO can improve the therapeutic effect on SSNHL, reduce blood viscosity and improve coagulation function, thus significantly promoting hearing recovery. Further, SSNHL treatment efficacy was influenced by age, time of onset, hearing threshold, presence or absence of tinnitus, plasma viscosity and serum C-reactive protein levels. The trial registration number for the present study was: NCT02563872.

In silico Single-Cell Analysis of Steroid-Responsive Gene Targets in the Mammalian Cochlea

Background

Treatment of many types of hearing instability in humans, including sudden sensorineural hearing loss, Meniere's disease, and autoimmune inner ear disease, rely heavily on the utilization of corticosteroids delivered both by oral and transtympanic routes. Despite this use, there is heterogeneity in the response to treatment with corticosteroids in humans with these diseases. The mechanisms by which corticosteroids exert their effect and the cell types in which they exert their effects in the inner ear remain poorly characterized. In this study, we localize steroid-responsive genes to cochlear cell types using previously published transcriptome datasets from the mammalian cochlea.

Methods

Steroid-responsive genes were localized to specific cochlear cell types using existing transcriptome datasets from wild-type mammalian cochlea exposed to systemic and transtympanic steroids, as well as previously published single-cell and single-nucleus RNA-sequencing datasets from the mammalian cochlea. Gene ontology (GO) analysis of differentially expressed genes (DEGs) was performed using PANTHER to investigate cellular processes implicated in transtympanic vs. systemic steroid action in the cochlea.

Results

Steroid-responsive genes were localized to specific cell types and regions in the cochlea including the stria vascularis, organ of Corti, and spiral ganglion neurons (SGN). Analyses demonstrate differential prevalence of steroid-responsive genes. GO analysis demonstrated steroid-responsive DEGs in the SGN to be associated with angiogenesis, apoptosis, and cytokine-mediated anti-inflammatory pathways.

Conclusions

Single-cell and single-nucleus transcriptome datasets localize steroid-responsive genes to specific regions in the cochlea. Further study of these regionally-specific steroid-responsive genes may provide insight into the mechanisms of and clinical response to corticosteroids in diseases of hearing instability.

Association of sudden sensorineural hearing loss with increased risk of insomnia: a nationwide population-based cohort study

STUDY OBJECTIVES

To evaluate the risk of insomnia in patients with sudden sensorineural hearing loss (SSNHL).

METHODS

A retrospective propensity score-matched cohort study was conducted using a nationwide representative sample from the National Sample Cohort 2002-2013 data from the Korea National Health Insurance Service. The SSNHL group (n = 631) included patients diagnosed with SSNHL between January 2002 and December 2005. The comparison group (four controls for every patient with SSNHL, n = 2,524) was selected using propensity score matching, according to sociodemographic factors and the year of enrollment. Each patient was monitored until 2013. Survival analysis, log-rank test, and Cox proportional hazards regression models were used to calculate the incidence, survival rate, and hazard ratio (HR) of insomnia for each group.

RESULTS

Among the 3155 individuals included in the study population (male, 48.6%), the overall incidence of insomnia during the 11-year follow-up was 1.4-fold higher in the SSNHL group than in the non-SSNHL group (106.3 vs. 138.3 per 10,000 person-years; adjusted HR 1.38; 95% confidence interval [CI] 1.08-1.78). Moreover, the adjusted HRs for developing insomnia (depression, 3.33 [95% CI, 2.22-5.01]; anxiety, 1.78 [95% CI, 1.27-2.53]; tinnitus, 1.56 [95% CI, 1.2-2.03]; dizziness, 1.76 [95% CI, 1.27-2.44]) were higher in patients with comorbidities.

CONCLUSIONS

This observational study suggests that SSNHL is associated with an increased incidence of insomnia. Specifically, findings from this study show that patients with tinnitus, depression, anxiety and dizziness had a higher risk of developing insomnia than those without tinnitus, depression, anxiety, and dizziness.

Direct SARS-CoV-2 infection of the human inner ear may underlie COVID-19-associated audiovestibular dysfunction

BACKGROUND

COVID-19 is a pandemic respiratory and vascular disease caused by SARS-CoV-2 virus. There is a growing number of sensory deficits associated with COVID-19 and molecular mechanisms underlying these deficits are incompletely understood.

METHODS

We report a series of ten COVID-19 patients with audiovestibular symptoms such as hearing loss, vestibular dysfunction and tinnitus. To investigate the causal relationship between SARS-CoV-2 and audiovestibular dysfunction, we examine human inner ear tissue, human inner ear in vitro cellular models, and mouse inner ear tissue.

RESULTS

We demonstrate that adult human inner ear tissue co-expresses the angiotensin-converting enzyme 2 (ACE2) receptor for SARS-CoV-2 virus, and the transmembrane protease serine 2 (TMPRSS2) and FURIN cofactors required for virus entry. Furthermore, hair cells and Schwann cells in explanted human vestibular tissue can be infected by SARS-CoV-2, as demonstrated by confocal microscopy. We establish three human induced pluripotent stem cell (hiPSC)-derived in vitro models of the inner ear for infection: two-dimensional otic prosensory cells (OPCs) and Schwann cell precursors (SCPs), and three-dimensional inner ear organoids. Both OPCs and SCPs express ACE2, TMPRSS2, and FURIN, with lower ACE2 and FURIN expression in SCPs. OPCs are permissive to SARS-CoV-2 infection; lower infection rates exist in isogenic SCPs. The inner ear organoids show that hair cells express ACE2 and are targets for SARS-CoV-2.

CONCLUSIONS

Our results provide mechanistic explanations of audiovestibular dysfunction in COVID-19 patients and introduce hiPSC-derived systems for studying infectious human otologic disease.

COVID-19-related sudden sensorineural hearing loss

BACKGROUND

Sudden sensorineural hearing loss (SSNHL) can be a feature of COVID-19. It may present alone or with other symptoms of the disease. However, there is little written in the literature about its occurrence. We aimed to evaluate the socio-clinical characteristics and outcome of confirmed mild- to moderate COVID-19 cases with SSNHL in Tikrit city, Iraq.

MATERIALS AND METHODS

This descriptive study was conducted at the Otolaryngology Department, Tikrit General Hospital, Tikrit city, Iraq. The period of the study was from December 1, 2020 to June 30, 2021.Mild and moderate COVID-19 subjects confirmed by real-time polymerase reaction were included in the study. Detailed demographic (age, gender, and smoking habit) and clinical characteristics (onset and duration of deafness, side, severity, associated ear, nose, and throat symptoms, and comorbidity) were recorded for every patient. Outcomes following the steroid treatment protocol were also registered.

RESULTS

SSNHL was identified in 26 patients, of whom 20 (76.9%) were women, 20 (76.9%) were in the age group ≥ 30 years, and 21 (80.8%) were non-smokers. Around three-quarters of the subjects were identified within the first week of deafness occurrence. Bilateral (18/26) was more common than unilateral deafness (8/26); therefore, the total number of deaf ears was 44. Besides, bilateral symmetrical deafness (13/18) outnumbered the asymmetrical type (5/18). Around three-quarters were of moderate severity. The most common otological symptom was tinnitus (25/26). The most common nose and throat symptom was anosmia (6/26). The mean hearing threshold before and after treatment with oral steroids ± intratympanic steroids was 50.91 ± 11.777 dB and 40.24 ± 15.693, respectively. One patient with bilateral SSNHL was lost to follow-up; the remaining number of deaf ears was 42, and half of them were partially improved. The outcome of the treatment showed no statistically significant relation with the duration, side, and severity of SSNHL (p>0.05).

CONCLUSION

The majority of COVID-19-related SSNHL cases presented within one week of onset, with bilateral outnumbering unilateral cases. Tinnitus was the most common associated symptom. Treatment with steroids achieved partial improvement in half of the cases, and this outcome was not affected by the duration, side, and severity of deafness.

A Case of Idiopathic Sequential Profound Bilateral Sudden Sensorineural Hearing Loss Occurring 37 Days After Unilateral Presentation

Sudden sensorineural hearing loss (SSNHL) is a common disorder; however, sequential, bilateral presentation of the disease is rarer than unilateral presentation. Clinical otologists usually focus on treating the side with impaired hearing when patients first present with unilateral SSNHL, and therefore, may not warn patients of the possibility of subsequent hearing impairment in the contralateral ear. Furthermore, it is professionally discouraging when a patient presents with profound, sequential SSNHL after initial treatment. This may adversely impact the doctor-patient relationship, even if the patient is offered the best possible care from their first visit. Herein, we report the case of a patient with profound, idiopathic, bilateral SSNHL with a time interval of 37 days between involvement of both ears. Even though high-dose steroids were administered intraorally and intratympanically, the patient’s hearing was not restored, and the patient eventually required bilateral cochlear implant surgery. Our report demonstrates that sequential, profound, bilateral SSNHL may manifest without any specific signs.

Idiopathic Sudden Sensorineural Hearing Loss: Speech Intelligibility Deficits Following Threshold Recovery

OBJECTIVES

This retrospective study tests the hypothesis that patients who have recovered from idiopathic sudden sensorineural hearing loss (SSNHL) show deficits in word recognition tasks that cannot be entirely explained by a loss in audibility.

DESIGN

We reviewed the audiologic profile of 166 patients presenting with a unilateral SSNHL. Hearing loss severity, degree of threshold recovery, residual hearing loss, and word recognition performance were considered as outcome variables. Age, route of treatment, delay between SSNHL onset and treatment, and audiogram configuration were considered as predictor variables.

RESULTS

Severity, residual hearing loss, and recovery were highly variable across patients. While age and onset-treatment delay could not account for the severity, residual hearing loss and recovery in thresholds, configuration of the SSNHL and overall inner ear status as measured by thresholds on the contralateral ear were predictive of threshold recovery. Speech recognition performance was significantly poorer than predicted by the speech intelligibility curve derived from the patient's audiogram.

CONCLUSIONS

SSNHL is associated with (1) changes in thresholds that are consistent with ischemia and (2) speech intelligibility deficits that cannot be entirely explained by a change in hearing sensitivity.

GRβ Regulates Glucocorticoid Resistance in Sudden Sensorineural Hearing Loss

BACKGROUND

In recent years, the incidence of sudden deafness has gradually increased, with a very limited understanding of its etiology and pathogenesis. Glucocorticoids are the first choice of the treatment, but some hormone-resistant patients are not sensitive to glucocorticoid therapy. The pathogenesis is not yet known. In this study, we aim to construct the HEI-OC1 cell line stably overexpressing Glucocorticoid Receptor Beta (GRβ), and identify its exact role in the cases of glucocorticoidresistant sudden deafness.

METHODS

We used the endotoxin lipopolysaccharide-stimulated cochlear hair cells (HEI-OC1) to investigate the relationship of inflammation factor IL-2, TNF alpha, and SRp30c with the high expression GRβ. We built a stable GRβ high expression HEI-OC1 cell line and clarified its effects on the therapeutic effect of dexamethasone. MTT assay, colony formation assay, CCK-8 assay, Western blot, and RT-qPCR were utilized for characterizations.

RESULTS

Dexamethasone reduced the LPS-induced inflammatory response from HEI-OC1 cells (p<0.05), detected by MTT assay. Dexamethasone could protect HEI-OC1 cells, but its protective effect was weakened due to the transfection of SRp30c over-expression plasmid (p<0.05). The transfection of SRp30c over-expression plasmid in HEI-OC1 cells could elevate the expressions of GRβ (p<0.05).

CONCLUSION

We clarified the mechanisms of high expression of GRβ in glucocorticoid-resistant sudden sensorineural hearing loss, and proved that the inhibition of SRp30c may act as a new treatment way of glucocorticoid-resistant sudden sensorineural hearing loss.

Management of sudden sensorineural hearing loss among primary care physicians in Canada: a survey study

BACKGROUND

Sudden Sensorineural Hearing Loss (SSNHL) is a medical emergency requiring immediate attention as delayed treatment can lead to permanent and devastating consequences. Primary care physicians are likely the first to be presented with SSNHL and therefore have the crucial role of recognizing it and initiating timely and appropriate management. The aim of this study was to gain insight into the current knowledge and practice trends pertaining to the diagnosis and management of SSNHL among family physicians in Canada.

METHODS

An 18-question survey targeting Canadian family physicians was marketed through two, physician-only discussion groups on the social media platform Facebook. Responses were collected between August 1st and December 22nd 2019 then aggregated and quantified.

RESULTS

52 family physicians submitted responses. 94.2% (n = 49) reported that in their practice, unilateral SSNHL warrants urgent referral to otolaryngology and 84.6% (n = 44) reported that unilateral sudden-onset hearing loss warrants urgent referral for audiological testing. 73.1% of participants (n = 38) reported that they would attempt to differentiate between conductive and sensorineural hearing loss if presented with unilateral, acute or sudden-onset hearing loss. 61.5% (n = 32) would rely on tuning fork tests to inform management decisions, as compared to 94.2% (n = 49) relying on case history and 88.5% (n = 46) on otoscopy. 76.9% (n = 40) would prescribe corticosteroids if presented with confirmed, unilateral SSNHL.

CONCLUSION

The majority of family physicians in the study would make appropriate referral and treatment decisions in the management of SSNHL, understanding it is a medical emergency. Tuning fork tests are under-utilized for informing management decisions compared to other means of differentiating conductive and sensorineural hearing loss. Further research is needed to understand why some family physicians do not prescribe corticosteroids for treatment of SSNHL, which may then identify any gaps in knowledge or inform improvements in clinical protocol.

Acute Labyrinthitis Revealing COVID-19

An 84-year-old man presented to the emergency department for acute vomiting associated with rotational vertigo and a sudden right sensorineural hearing loss. A left peripheral vestibular nystagmus was highlighted. The patient was afebrile, without respiratory signs or symptoms. Blood sampling at admission showed lymphopenia, thrombopenia and neutrophil polynucleosis, without elevation of C reactive protein. Cerebral magnetic resonance imaging eliminated a neurovascular origin. Vestibule, right semicircular canals and cochlear FLAIR hypersignals were highlighted, leading to the diagnosis of right labyrinthitis. A nasopharyngeal swab sampled at admission returned positive for SARS CoV2 by polymerase chain reaction. The etiologic investigation, including syphilitic and viral research, was otherwise negative. An oral corticotherapy (prednisone 70 mg daily) was introduced, followed by a progressive clinical recovery. Although acute otitis media have already been highlighted as an unusual presentation of COVID-19, radiology-proven labyrinthitis had to our knowledge, never been described to date.

Predicting hearing recovery following treatment of idiopathic sudden sensorineural hearing loss with machine learning models

PURPOSE

Idiopathic sudden sensorineural hearing loss (ISSHL) is an emergency otological disease, and its definite prognostic factors remain unclear. This study applied machine learning methods to develop a new ISSHL prognosis prediction model.

MATERIALS AND METHODS

This retrospective study reviewed the medical data of 244 patients who underwent combined intratympanic and systemic steroid treatment for ISSHL at a tertiary referral center between January 2015 and October 2019. We used 35 variables to predict hearing recovery based on Siegel's criteria. In addition to performing an analysis based on the conventional logistic regression model, we developed prediction models with five machine learning methods: least absolute shrinkage and selection operator, decision tree, random forest (RF), support vector machine, and boosting. To compare the predictive ability of each model, the accuracy, precision, recall, F-score, and the area under the receiver operator characteristic curves (ROC-AUC) were calculated.

RESULTS

Former otological history, ear fullness, delay between symptom onset and treatment, delay between symptom onset and intratympanic steroid injection (ITSI), and initial hearing thresholds of the affected and unaffected ears differed significantly between the recovery and non-recovery groups. While the RF method (accuracy: 72.22%, ROC-AUC: 0.7445) achieved the highest predictive power, the other methods also featured relatively good predictive power. In the RF model, the following variables were identified to be important for hearing-recovery prediction: delay between symptom onset and ITSI or the initial treatment, initial hearing levels of the affected and non-affected ears, body mass index, and a previous history of hearing loss.

CONCLUSIONS

The machine learning models predictive of hearing recovery following treatment for ISSHL showed superior predictive power relative to the conventional logistic regression method, potentially allowing for better patient treatment outcomes.

Comparison of two different intratympanic corticosteroid injection protocols as salvage treatments for idiopathic sudden sensorineural hearing loss

PURPOSE

We aimed to investigate the effect of interval length and total count of intratympanic steroid (ITS) injections in salvage treatment of patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

METHODS

This retrospective case-control study included 64 patients with ISSNHL, who were treated with ITS injections as salvage therapy at a tertiary referral centre. From September 2019 to December 2020, 32 patients received up to four injections every 2-4 days (revised-protocol group). These patients were 1:1 matched to patients, who received up to three injections at 1-week intervals between January 2014 and August 2019 (initial-protocol group). Hearing outcomes of the two groups were compared.

RESULTS

Both ITS salvage treatment protocols resulted in a statistically significant hearing improvement (p < 0.05). The initial-protocol declined hearing thresholds by 12 ± 11.7 dB (p < 0.001, d = 1, P = 99%). Mean hearing function was improved by 13.4 ± 19.1 dB in the revised-protocol group [p < 0.001, d = 0.7, P = 98%]. A clinically significant hearing improvement (> 10 dB) was seen in 18 patients (58.1%) in the initial-protocol group and in 14 patients (41.9%) in the revised-protocol group. A comparison of the hearing outcomes between protocol groups revealed no statistically significant differences (p > 0.05).

CONCLUSION

These results indicate that a shorter injection interval does not lead to better hearing outcomes in ITS salvage treatment for ISSNHL. Moreover, fewer ITS injections may reduce costs, physical/mental stress of the patients and lower the risk of persistent tympanic perforations.

Bilateral Sudden Sensorineural Hearing Loss and Intralabyrinthine Hemorrhage in a Patient With COVID-19

OBJECTIVE

To describe a case of bilateral sudden sensorineural hearing loss (SSNHL) and intralabyrinthine hemorrhage in a patient with COVID-19.

STUDY DESIGN

Clinical capsule report.

SETTING

Tertiary academic referral center.

PATIENT

An adult woman with bilateral SSNHL, aural fullness, and vertigo with documented SARS-CoV-2 infection (IgG serology testing).

INTERVENTIONS

High-dose oral prednisone with taper, intratympanic dexamethasone.

MAIN OUTCOME MEASURES

Audiometric testing, MRI of the internal auditory canal with and without contrast.

RESULTS

A patient presented with bilateral SSNHL, bilateral aural fullness, and vertigo. Serology testing performed several weeks after onset of symptoms was positive for IgG COVID-19 antibodies. MRI showed bilateral intralabyrinthine hemorrhage (left worse than right) and no tumor. The patient was treated with two courses of high-dose oral prednisone with taper and a left intratympanic dexamethasone injection, resulting in near-resolution of vestibular symptoms, a fluctuating sensorineural hearing loss in the right ear, and a severe to profound mixed hearing loss in the left ear.

CONCLUSIONS

COVID-19 may have otologic manifestations including sudden SSNHL, aural fullness, vertigo, and intralabyrinthine hemorrhage.

Biomarkers for Inner Ear Disorders: Scoping Review on the Role of Biomarkers in Hearing and Balance Disorders

The diagnostics of inner ear diseases are primarily functional, but there is a growing interest in inner ear biomarkers. The present scoping review aimed to elucidate gaps in the literature regarding the definition, classification system, and an overview of the potential uses of inner ear biomarkers. Relevant biomarkers were categorized, and their possible benefits were evaluated. The databases OVID Medline, EMBASE, EBSCO COINAHL, CA PLUS, WOS BIOSIS, WOS Core Collection, Proquest Dissertations, Theses Global, PROSPERO, Cochrane Library, and BASE were searched using the keywords “biomarker” and “inner ear”. Of the initially identified 1502 studies, 34 met the inclusion criteria. The identified biomarkers were classified into diagnostic, prognostic, therapeutic, and pathognomonic; many were detected only in the inner ear or temporal bone. The inner-ear-specific biomarkers detected in peripheral blood included otolin-1, prestin, and matrilin-1. Various serum antibodies correlated with inner ear diseases (e.g., anti-type II collagen, antinuclear antibodies, antibodies against cytomegalovirus). Further studies are advised to elucidate the clinical significance and diagnostic or prognostic usage of peripheral biomarkers for inner ear disorders, filling in the literature gaps with biomarkers pertinent to the otology clinical practice and integrating functional and molecular biomarkers. These may be the building blocks toward a well-structured guideline for diagnosing and managing some audio-vestibular disorders.

Migraine and risk of sudden sensorineural hearing loss: A systematic review and meta-analysis

OBJECTIVE

The pathophysiology of idiopathic sudden sensorineural hearing loss (SSNHL) is poorly understood. This study aimed to explore the association of migraine and risk of SSNHL in a meta-analysis of population-based cohort studies.

METHODS

A systematic literature search of studies published until December 2019 was carried out in Medline, Embase, Scopus, Web of Science, and Google Scholar using appropriate keywords. References of the retrieved articles were also examined for inclusion. Random-effects meta-analysis was performed by calculating pooled hazard ratio (HR) and associated 95% confidence interval (CI) using the DerSimonian and Laird method while considering conceptual heterogeneity.

RESULTS

Three eligible cohort studies, with 282 250 participants, were included. In total, 56 450 had migraine, and 225 800 had no migraine. Of those with migraine, 0.88% had SSNHL, and among those without migraine, 0.59% had SSNHL. Pooled HR for the risk of SSNHL was 1.84 (95% CI: 1.11-2.57; P < .001). In cohort studies on females, migraine was not significantly the risk of SSHL than no migraine. However, in male cohort studies, the migraine had a higher risk of SSHL than no migraine (HR = 1.50; 95% CI: 1.17-1.83; P < .001). The pooled HR of migraine with the risk of SSNHL was 1.37 (95% CI: 1.16-1.58, P < .001) in people with <40 years old and 1.39 (95% CI: 1.17-1.60; P < .001) in people >40 years old.

CONCLUSIONS

Individuals with migraine patients are at a higher risk of developing SSHL. Different age and sex migraine subgroups showed a higher proportion of SSNHL cases compared to nonmigraineurs.

Metabolic syndrome and idiopathic sudden sensori-neural hearing loss

The purpose of this study was to evaluate the association between the presence of Metabolic Syndrome (MetS) and idiopathic sudden sensorineural hearing loss (ISSHL) and the impact of MetS on recovery of patients with ISSHL. 39 Patients with ISSHL and 44 controls were enrolled in this study. Demographic, clinical characteristics and hearing recovery were evaluated. MetS was defined according to the diagnostic criteria of International Diabetes Federation (IDF) consensus definition. Patients affected by ISSHL presented a body mass index (BMI), waist circumference, waist hip ratio (WHR), fasting glucose and blood pressure significantly higher compared to controls. Considering patients with central obesity, 5 controls and 15 ISSHL patients met the criteria of MetS. According to Siegel criteria, a complete or partial recovery was observed in 60% of patients with MetS and in 91,66% of patients without MetS. MetS was associated with ISSHL and this association negatively influenced the hearing recovery of these patients.

Genetic Polymorphisms in Sudden Sensorineural Hearing Loss: An Update

OBJECTIVE

To investigate the association between genetic polymorphisms and sudden sensorineural hearing loss (SSNHL). Most of the SSNHL cases still remain idiopathic, and several etiopathogenetic hypotheses, including a genetic predisposition, have been proposed.

METHODS

A literature review was conducted using different databases: Medline/PubMed, EMBASE, and CINAHL, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All databases have been searched from May 2016 to April 2020.

RESULTS

Genetic susceptibility could represent a key element in the pathogenesis of SSNHL. A number of genetic polymorphisms related to (1) inner ear microvascular disease and endothelial dysfunction and (2) to inner ear oxidative stress and inflammation have been addressed in the current literature.

CONCLUSIONS

The potential identification of a genetic profile related to SSNHL could provide a more accurate prognostic evidence of idiopathic SSNHL (ISSNHL), offering to the patients not only early-prevention strategies but eventually information on various inheritance modalities.

Comparison of Therapeutic Results with/without Additional Hyperbaric Oxygen Therapy in Idiopathic Sudden Sensorineural Hearing Loss: A Randomized Prospective Study

OBJECTIVE

To assess the efficacy of the combination of hyperbaric oxygen (HBO) and pharmacological treatment in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) and define patients amenable for HBO therapy.

METHODS

Prospective, randomized, trial involving 136 cases with unilateral ISSNHL that were randomly divided into 2 groups: the pharmacological treatment (P) group and HBO + pharmacological treatment (HBO+P) group, which received additional HBO for 14 days besides the pharmacological treatments. Pure tone audiometry gain larger than 15 dBHL was defined as success, and the success rate of each group was calculated.

RESULTS

The overall success rate of the HBO+P group and the P group is 60.6% (40/66) and 42.9% (30/70), respectively (p < 0.05). Furthermore, patients with mild-moderate baseline hearing loss, aged ≤50 years, receiving treatment in ≤14 days, or without accompanied dizziness/vertigo in the HBO+P group had higher success rate than the P group (p < 0.05).

CONCLUSIONS

HBO combined with pharmacological treatments leads to better hearing recovery than pharmacological treatments alone.

Serum Renin Levels in Sudden Sensorineural Hearing Loss

Objective:

The aim of this study was to investigate the serum renin levels of patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

Material and Methods:

Twenty-four patients with ISSNHL and 24 asymptomatic healthy volunteers were included in the study. Subjects underwent pure-tone audiometry and serum renin levels were measured.

Results:

There were 14 women (mean age:42.35 ± 9.53) and 10 men (mean age:43.8 ± 6.87) in the patient group. There were 14 women (mean age:42.4 ± 4.7) and 10 men (mean age:41.4 ± 4.59) in the control group. ISSNHL was detected on the right side in 13 patients and on the left side in 11 patients. Serum renin levels of the patients and controls were 788.01 ± 327.8 and 282.37 ± 107.73 pg/mL, respectively. The serum renin levels were found to be significantly higher in the patient group compared to the control group ( P ≤ .001). There was a statistically significant strong positive correlation between serum renin level and the severity of hearing loss ( r = 0.77; P = .001).

Conclusion:

Serum renin levels of patients with ISSNHL were higher than controls. There was a statistically significant strong positive correlation between serum renin level and the severity of hearing loss.

Using corticosteroids to treat sudden sensorineural hearing loss in pregnancy: A case report and literature review

Sudden sensorineural hearing loss (SSNHL) can manifest in pregnancy, but very few cases of SSNHL in pregnancy have been reported and none has been reported in the United States. Additionally, there are no established guidelines for how to treat SSNHL in pregnancy. The purpose of this report is to describe how SSNHL presents in pregnancy, to evaluate other etiologies and discuss current treatment options. A 35-year-old parous woman at 22 weeks of gestation, with a 2-week history of left-sided hearing loss, was shown to have a speech recognition threshold of 70 dB in her left ear. Otolaryngology confirmed the diagnosis of SSNHL. The patient was prescribed an oral prednisone taper that helped alleviate the hearing loss. She had an uncomplicated delivery and treatment with corticosteroids had no adverse consequences for the patient. After ruling out etiologies of SSNHL, corticosteroids may be used safely and efficaciously to treat SSNHL during the second trimester of pregnancy.

Investigation of the prognostic role of neutrophil-to-lymphocyte ratio in Idiopathic Sudden Sensorineural Hearing Loss based on propensity score matching: a retrospective observational study

INTRODUCTION

The aetiology, management and prognosis of idiopathic Sdden Sensorineural Hearing Loss (ISSNHL) are still uncertain despite adequate investigation.

OBJECTIVE

We conducted the present study to investigate the possible relationship between the neutrophil-to-lymphocyte ratio (NLR) and the prognosis of ISSNHL based on PSM.

METHODS

This was a retrospective observational study. Data and statistical analyses were performed using the SPSS statistical program (SPSS 19.0). PSM was performed using STATA (15.0).

RESULTS

NLR = 3.42 was the cut-off value. After PSM, 84 pairs of patients were successfully matched. The number of patients in the effective group with the NLR < 3.42 and NLR < 3.42 were significantly different (P < 0.001).

CONCLUSION

The NLR is an inexpensive and reliable index to predict the ISSNHL. We hold the view that the NLR can be a reliable factor for clinical doctors to predict the prognosis in ISSNHL. To further prove that the NLR is a powerful prognostic factor in ISSNHL, larger prospective studies are required in the future.

Clinical Practice Guideline: Sudden Hearing Loss (Update)

OBJECTIVE

Sudden hearing loss is a frightening symptom that often prompts an urgent or emergent visit to a health care provider. It is frequently but not universally accompanied by tinnitus and/or vertigo. Sudden sensorineural hearing loss affects 5 to 27 per 100,000 people annually, with about 66,000 new cases per year in the United States. This guideline update provides evidence-based recommendations for the diagnosis, management, and follow-up of patients who present with sudden hearing loss. It focuses on sudden sensorineural hearing loss in adult patients aged ≥18 years and primarily on those with idiopathic sudden sensorineural hearing loss. Prompt recognition and management of sudden sensorineural hearing loss may improve hearing recovery and patient quality of life. The guideline update is intended for all clinicians who diagnose or manage adult patients who present with sudden hearing loss.

PURPOSE

The purpose of this guideline update is to provide clinicians with evidence-based recommendations in evaluating patients with sudden hearing loss and sudden sensorineural hearing loss, with particular emphasis on managing idiopathic sudden sensorineural hearing loss. The guideline update group recognized that patients enter the health care system with sudden hearing loss as a nonspecific primary complaint. Therefore, the initial recommendations of this guideline update address distinguishing sensorineural hearing loss from conductive hearing loss at the time of presentation with hearing loss. They also clarify the need to identify rare, nonidiopathic sudden sensorineural hearing loss to help separate those patients from those with idiopathic sudden sensorineural hearing loss, who are the target population for the therapeutic interventions that make up the bulk of the guideline update. By focusing on opportunities for quality improvement, this guideline should improve diagnostic accuracy, facilitate prompt intervention, decrease variations in management, reduce unnecessary tests and imaging procedures, and improve hearing and rehabilitative outcomes for affected patients.

METHODS

Consistent with the American Academy of Otolaryngology-Head and Neck Surgery Foundation's "Clinical Practice Guideline Development Manual, Third Edition" (Rosenfeld et al. Otolaryngol Head Neck Surg. 2013;148[1]:S1-S55), the guideline update group was convened with representation from the disciplines of otolaryngology-head and neck surgery, otology, neurotology, family medicine, audiology, emergency medicine, neurology, radiology, advanced practice nursing, and consumer advocacy. A systematic review of the literature was performed, and the prior clinical practice guideline on sudden hearing loss was reviewed in detail. Key Action Statements (KASs) were updated with new literature, and evidence profiles were brought up to the current standard. Research needs identified in the original clinical practice guideline and data addressing them were reviewed. Current research needs were identified and delineated.

RESULTS

The guideline update group made strong recommendations for the following: (KAS 1) Clinicians should distinguish sensorineural hearing loss from conductive hearing loss when a patient first presents with sudden hearing loss. (KAS 7) Clinicians should educate patients with sudden sensorineural hearing loss about the natural history of the condition, the benefits and risks of medical interventions, and the limitations of existing evidence regarding efficacy. (KAS 13) Clinicians should counsel patients with sudden sensorineural hearing loss who have residual hearing loss and/or tinnitus about the possible benefits of audiologic rehabilitation and other supportive measures. These strong recommendations were modified from the initial clinical practice guideline for clarity and timing of intervention. The guideline update group made strong recommendations against the following: (KAS 3) Clinicians should not order routine computed tomography of the head in the initial evaluation of a patient with presumptive sudden sensorineural hearing loss. (KAS 5) Clinicians should not obtain routine laboratory tests in patients with sudden sensorineural hearing loss. (KAS 11) Clinicians should not routinely prescribe antivirals, thrombolytics, vasodilators, or vasoactive substances to patients with sudden sensorineural hearing loss. The guideline update group made recommendations for the following: (KAS 2) Clinicians should assess patients with presumptive sudden sensorineural hearing loss through history and physical examination for bilateral sudden hearing loss, recurrent episodes of sudden hearing loss, and/or focal neurologic findings. (KAS 4) In patients with sudden hearing loss, clinicians should obtain, or refer to a clinician who can obtain, audiometry as soon as possible (within 14 days of symptom onset) to confirm the diagnosis of sudden sensorineural hearing loss. (KAS 6) Clinicians should evaluate patients with sudden sensorineural hearing loss for retrocochlear pathology by obtaining magnetic resonance imaging or auditory brainstem response. (KAS 10) Clinicians should offer, or refer to a clinician who can offer, intratympanic steroid therapy when patients have incomplete recovery from sudden sensorineural hearing loss 2 to 6 weeks after onset of symptoms. (KAS 12) Clinicians should obtain follow-up audiometric evaluation for patients with sudden sensorineural hearing loss at the conclusion of treatment and within 6 months of completion of treatment. These recommendations were clarified in terms of timing of intervention and audiometry and method of retrocochlear workup. The guideline update group offered the following KASs as options: (KAS 8) Clinicians may offer corticosteroids as initial therapy to patients with sudden sensorineural hearing loss within 2 weeks of symptom onset. (KAS 9a) Clinicians may offer, or refer to a clinician who can offer, hyperbaric oxygen therapy combined with steroid therapy within 2 weeks of onset of sudden sensorineural hearing loss. (KAS 9b) Clinicians may offer, or refer to a clinician who can offer, hyperbaric oxygen therapy combined with steroid therapy as salvage therapy within 1 month of onset of sudden sensorineural hearing loss.

DIFFERENCES FROM PRIOR GUIDELINE

Incorporation of new evidence profiles to include quality improvement opportunities, confidence in the evidence, and differences of opinion Included 10 clinical practice guidelines, 29 new systematic reviews, and 36 new randomized controlled trials Highlights the urgency of evaluation and initiation of treatment, if treatment is offered, by emphasizing the time from symptom occurrence Clarification of terminology by changing potentially unclear statements; use of the term sudden sensorineural hearing loss to mean idiopathic sudden sensorineural hearing loss to emphasize that >90% of sudden sensorineural hearing loss is idiopathic sudden sensorineural hearing loss and to avoid confusion in nomenclature for the reader Changes to the KASs from the original guideline: KAS 1-When a patient first presents with sudden hearing loss, conductive hearing loss should be distinguished from sensorineural. KAS 2-The utility of history and physical examination when assessing for modifying factors is emphasized. KAS 3-The word "routine" is added to clarify that this statement addresses nontargeted head computerized tomography scan that is often ordered in the emergency room setting for patients presenting with sudden hearing loss. It does not refer to targeted scans, such as temporal bone computerized tomography scan, to assess for temporal bone pathology. KAS 4-The importance of audiometric confirmation of hearing status as soon as possible and within 14 days of symptom onset is emphasized. KAS 5-New studies were added to confirm the lack of benefit of nontargeted laboratory testing in sudden sensorineural hearing loss. KAS 6-Audiometric follow-up is excluded as a reasonable workup for retrocochlear pathology. Magnetic resonance imaging, computerized tomography scan if magnetic resonance imaging cannot be done, and, secondarily, auditory brainstem response evaluation are the modalities recommended. A time frame for such testing is not specified, nor is it specified which clinician should be ordering this workup; however, it is implied that it would be the general or subspecialty otolaryngologist. KAS 7-The importance of shared decision making is highlighted, and salient points are emphasized. KAS 8-The option for corticosteroid intervention within 2 weeks of symptom onset is emphasized. KAS 9-Changed to KAS 9A and 9B. Hyperbaric oxygen therapy remains an option but only when combined with steroid therapy for either initial treatment (9A) or salvage therapy (9B). The timing of initial therapy is within 2 weeks of onset, and that of salvage therapy is within 1 month of onset of sudden sensorineural hearing loss. KAS 10-Intratympanic steroid therapy for salvage is recommended within 2 to 6 weeks following onset of sudden sensorineural hearing loss. The time to treatment is defined and emphasized. KAS 11-Antioxidants were removed from the list of interventions that the clinical practice guideline recommends against using. KAS 12-Follow-up audiometry at conclusion of treatment and also within 6 months posttreatment is added. KAS 13-This statement on audiologic rehabilitation includes patients who have residual hearing loss and/or tinnitus who may benefit from treatment. Addition of an algorithm outlining KASs Enhanced emphasis on patient education and shared decision making with tools provided to assist in same.

Investigation of Stress Levels before the Onset of Idiopathic Sudden Sensorineural Hearing Loss

OBJECTIVES

We hypothesized that patients with idiopathic sudden sensorineural hearing loss (ISSHL) would have experienced more stress prior to the onset than they typically did. This study investigated stress levels in patients before the onset of ISSHL.

MATERIALS AND METHODS

Forty-two patients with ISSHL were investigated. We used an original questionnaire to evaluate subjective stress levels in 1 week before onset. Serum hemoglobin A1c (HbA1c) and total cholesterol were examined to evaluate biochemical stress markers reflecting the preceding 1 to 2 months. The results on admission were compared with those at the follow-up visit.

RESULTS

Significantly more patients reported greater physical exhaustion, greater mental exhaustion, or a worse physical condition on admission than at follow-up (p<0.01, for each variable). On admission, 81% of patients reported greater than normal stress with regard to at least 1 of 3 items. The mean serum HbA1c was slightly but nonsignificantly lower at the follow-up visit (p=0.10), while the mean serum total cholesterol was significantly lower at follow-up than on admission (p<0.01).

CONCLUSION

The results indicate that patients were under a greater degree of stress before the onset of ISSHL, suggesting that stress plays a role in inducing ISSHL.

Fluctuating Sensorineural Hearing Loss

BACKGROUND

Several otologic conditions can present with fluctuating sensorineural hearing loss, including Ménière's disease, autoimmune inner ear disease, and enlarged vestibular aqueduct. Although these 3 etiologies vary greatly, distinguishing between these conditions at initial presentation can be challenging. Furthermore, initial treatment of these conditions is often similar. In this review, we discuss historical and current perspectives on diagnosis and treatment of these conditions.

SUMMARY

A literature search was performed regarding fluctuating hearing loss, and current treatment of these etiologies of fluctuating hearing loss was summarized. Immediate measures at the onset of acute hearing loss include corticosteroid therapy, while preventative and chronic therapies, which can limit disease severity and frequency, vary based on the specific condition treated. Key Messages: Fluctuating hearing loss can represent a range of pathologies, but the precise etiology may not be clear at initial presentation. Timely treatment and long-term follow-up, along with appropriate diagnostics, are necessary to optimize long-term hearing.

Role of viral infection in sudden hearing loss

According to a recent epidemiological survey, the incidence of sudden sensorineural hearing loss (SSNHL) is increasing yearly. The cause of SSNHL is of great interest in research. To date, viral infection, vascular occlusion, abnormal cellular stress responses within the cochlea, and immune-mediated mechanisms are considered the most likely etiologies of this disease. Among these etiologies, the relationship between viral infection and sudden deafness has been unclear. In this review, we mainly discuss the viral hypothesis of SSNHL. There is little research proving or clearly indicating the pathogenesis of this disease. Further research is needed to elucidate the precise etiopathogenesis to better understand SSNHL and establish more suitable treatment to help restore hearing in affected patients.

Effects of meteorological factor and air pollution on sudden sensorineural hearing loss using the health claims data in Busan, Republic of Korea

PURPOSE

Specific meteorological factors, including air pollution in the form of particulate matter (PM), affect the development of otologic disease and have adverse effects on the cardiovascular and respiratory systems. This study investigated relationships between the development of sudden sensorineural hearing loss(SSNHL) and meteorological factor with air pollution including PM.

MATERIALS AND METHODS

The daily patient number in 2015 admitted to the hospital with SSNHL were extracted from the Health Insurance Review and Assessment Service Bigdata in Busan. The meteorological factors and air pollution data of Busan area were obtained from meteorological stations in Busan. The relationship between the number of hospitalizations and the climatic factors was checked.

RESULTS

SSNHL patient group showed more common in women, and the highest rates were observed in patients in their 50s. The daily mean patient numbers were 2.27. The number of SSNHL patients in spring was statistically significantly higher than that in summer. The mean daily PM10 and PM2.5 concentrations were 48.0 and 29.4 μg/m³, respectively. The mean wind speed, maximum wind speed and daily atmospheric pressure range was weakly positively associated with SSNHL patient number. There were weak negative correlations between maximum PM2.5 and SSNHL admissions. The mean temperature and wind chill index showed non-significantly negative relationships with SSNHL admissions.

CONCLUSIONS

In Busan area, statistically significant weak relationships were detected between the daily numbers of patients admitted to the hospital with SSNHL and meteorological data, including PM level. Further investigation of these associations is required.

Hormone therapy is not associated with the risk of sudden sensorineural hearing loss in postmenopausal women: a 10-year nationwide population-based study

OBJECTIVE

The association between hormone therapy (HT) and the risk for sudden sensorineural hearing loss (SSNHL) in postmenopausal women has been described only in case reports. No large study has further evaluated the association between HT and the risk of SSNHL in postmenopausal women. The objective of our study was to investigate whether postmenopausal women with HT exhibit a risk of SSNHL.

METHODS

This matched cohort study enrolled 13,112 postmenopausal women 45 to 79 years of age who used HT between 2000 and 2010; they were selected from the National Health Insurance Research Database of Taiwan, and 39,336 participants without HT use were enrolled as controls matched by age and index year at a 1:3 ratio.

RESULTS

We used a Cox proportional hazards regression model to identify the risk of SSNHL during 10 years of follow-up, and the results indicated no significant increase in the proportion of postmenopausal women with HT use (P = 0.814) who developed SSNHL compared with those without HT use (1.14%, 150/13, 112 vs 1.12%, 439/39, 336). After adjustment for age and other variables, the adjusted hazard ratio was 0.78 (95% CI, 0.308-1.025, P = 0.762) and showed no association between HT use and SSNHL development in postmenopausal women.

CONCLUSIONS

Our results showed that HT was not associated with the risk of SSNHL in postmenopausal women over a 10-year follow-up study.