Systematic review and meta-analysis of the risk factors for sudden sensorineural hearing loss in adults

Idiopathic sudden sensorineural hearing loss: A review focused on the contribution of vascular pathologies

Idiopathic sudden sensorineural hearing loss (ISSNHL) is characterized by abruptly appearing hearing loss, sometimes accompanied by vertigo. Vascular pathologies (e.g., cochlear ischemia, or cochlear infarction) are one of the most likely causes of ISSNHL. This review aims to present current understanding of inner ear anatomy, clinical features of ISSNHL, and its treatment strategies. The labyrinthine artery is the only end artery supplying blood to the inner ear, and it has three branches: the anterior vestibular artery, the main cochlear artery, and the vestibulo-cochlear artery (VCA). Occlusion of the VCA can be caused by a variety of factors. The VCA courses through a narrow bone canal. ISSNHL is usually diagnosed after excluding retrocochlear pathologies of sudden sensorineural hearing loss (SSNHL), such as vestibular schwannoma. Therefore, a head MRI or assessing auditory brainstem responses are recommended for patients with SSNHL. Severe SSNHL patients with high CHADS2 scores, an index of stroke risk, have a significantly lower rate of vestibular schwannoma than severe SSNHL patients with low CHADS2 scores, suggesting that severe ISSNHL in individuals at high risk of stroke is caused by vascular impairments. Intralabyrinthine hemorrhage causes SSNHL or vertigo, as in ISSNHL. The diagnosis of intralabyrinthine hemorrhage requires careful interpretation of MRI, and a small percentage of patients diagnosed with ISSNHL may in fact have intralabyrinthine hemorrhage. Many studies have reported an association between ISSNHL and atherosclerosis or cardiovascular risk factors (e.g., diabetes mellitus, hypertension, dyslipidemia and cardiovascular disease), and subsequent risk of stroke in patients with ISSNHL may be elevated compared to controls. Increased hearing level on the healthy ear side, high Framingham risk score, high neutrophil-to-lymphocyte ratio, high platelet-to-lymphocyte ratio, and severe white matter lesions may be poor prognostic factors for patients with ISSNHL. The association between thrombosis-related genes and susceptibility to ISSNHL has been reported in many studies (e.g., coagulation factor 2, coagulation factor 5, plasminogen activator inhibitor-1, platelet-associated genes, a homocysteine metabolism-related enzyme gene, endothelin-1, nitric oxide 3, phosphodiesterase 4D, complement factor H, and protein kinase C-eta). Treatment of ISSNHL with the aim of mitigating the vascular impairment in the inner ear includes systemically administered steroids, intratympanic steroid injections, hyperbaric oxygen therapy, prostaglandin E1, defibrinogenation therapy, and hydrogen inhalation therapy, but there is currently no evidence-based treatment for ISSNHL. Breakthroughs in the unequivocal diagnosis and treatment of ISSNHL due to vascular impairment are crucial to improve quality of life.

MRI Safety of Stapes Prostheses: A Systematic Review

OBJECTIVE

To assess magnetic resonance imaging (MRI) safety of stapes prostheses.

DATA SOURCES

Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases were searched from inception to November 2021 following PRISMA guidelines.

REVIEW METHODS

Studies reporting evidence of stapes prosthesis displacement or interaction in adult or pediatric implant recipients undergoing MRI. Cadaveric, animal, and basic studies with nonhuman data were also included.

RESULTS

From an initial search of 123 articles, 42 full-text studies were evaluated for eligibility and 19 studies that met the inclusion criteria were included. Motion artifact was reported in a few stainless steel prosthesis types in vitro; however, such displacement was not observed in human cadaver temporal bone studies and had no adverse reported outcomes. A small subgroup of patients in the 1980s received a ferromagnetic stainless steel stapes implant that was recalled and has not been used since 1987. Patients with implants performed in the 1980s should be directed to 1.5T scanners from an abundance of caution.

CONCLUSION

Modern (post-1987) stapes prostheses do not pose a risk in vivo when exposed to the magnetic fields of MRI scanners.

Importance of small vessel disease as a possible cause of sudden sensorineural hearing loss

OBJECTIVE

Vascular disease like small-vessel disease (SVD) is the most likely cause among the potential causes of Sudden sensorineural hearing loss (SSNHL). Understanding the relationship between SVD and SSNHL is crucial for developing effective prevention and treatment strategies. To confirm the relationship between SVD and SSNHL, the effect of SVD is confirmed by focusing on the duration and recurrence of SSNHL.

METHODS

This article reports a retrospective observational study that investigated the relationship between SVD and SSNHL using the South Korea Health Insurance Review and Assessment Service (HIRA) database from 2010 to 2020. This retrospective observational study included 319,569 SSNHL patients between 2010 and 2020.

RESULTS

Participant demographics were controlled using Propensity Score Matching. The hazard ratios (HR) for the effect of SVD on the duration of SSNHL were 1.045 for the group with SVD before the onset of SSNHL and 1.234 for the group with SVD after the onset of SSNHL. SVD was statistically significant for the recurrence of SSNHL, with an odds ratio of 1.312 in the group with SVD compared to the group without SVD. The HR for the period until a recurrence in the group with SVD was 1.062.

CONCLUSIONS

The study identified SVD as a possible cause of SSNHL and found that the duration of SSNHL increased only in the presence of SVD. SVD also affected the recurrence of SSNHL, with the recurrence rate being 1.312 times higher in the group with SVD.

Association between Sudden Sensorineural Hearing Loss and the Risk of Cardio Cerebrovascular Disease

OBJECTIVES

This study investigated the association between sudden sensorineural hearing loss (SSNHL) and the risk of cardio-cerebrovascular disease (CCVD) among older adults in South Korea.

METHODS

Data from 38,426 patients in the Korean National Health Insurance Service-Senior Cohort from 2002 to 2019 were collected. The risk of CCVD includes both stroke and acute myocardial infarction. Propensity score matching (1:1) was used to identify pairs of individuals with and without SSNHL (n = 19,213 for cases and controls). Cox proportional hazards regression models were used to analyze the associations between variables.

RESULTS

Patients with SSNHL had a higher risk of CCVD (hazard ratio [HR] = 1.17, 95% confidence interval [CI] = 1.11-1.24) compared to those without. The risk of CCVD was higher among those who experienced a stroke than those who did not (HR = 1.17 95% CI = 1.10-1.25). Compared to their matched controls, patients with SSNHL were 1.69 times (HR = 1.69 CI = 1.46-1.94) more likely to have CCVD during the first 12 months of the follow-up period.

CONCLUSION

Older patients with SSNHL are at an increased risk of CCVD. Hence, a more attentive approach featuring aggressive monitoring of patients with SSNHL is required to lessen their risk of CCVD.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:2372-2376, 2024.

A prognostic value of estimated pulse wave velocity in idiopathic sudden sensorineural hearing loss

PURPOSE

Arterial stiffness, represented by estimated pulse wave velocity (ePWV), is the independent surrogate marker for cardiovascular event. The aim of the study was to investigate the significance of ePWV in the treatment outcome of idiopathic sudden sensorineural hearing loss (SSNHL).

METHODS

One hundred and ten patients with idiopathic SSNHL who hospitalized between April 2019 and March 2022 were evaluated. Arterial stiffness was calculated with formula for ePWV and other cardiovascular parameters of body mass index (BMI), and serum lipid level was determined. All patients received systemic high-dose steroid therapy and intratympanic steroid injections as a salvage management. Treatment outcome was assessed at 6 months after treatment, and classified as recovery and nonrecovery groups according to hearing recovery.

RESULTS

The initial pure-tone hearing threshold was 72.6 ± 23.8 dB and final hearing threshold was 52.63 ± 31.10 dB. After treatment, 60 (54.5%) patients included in recovery group and other 50 (45.5%) were classified as nonrecovery group. Age, days of onset to treatment, BMI, waist circumference, and ePWV were higher in the nonrecovery group compared to recovery group in univariate analysis (p = 0.039, p = 0.049, p = 0.003, p = 0.004, p = 0.007, respectively). In multivariate analysis, days of onset to treatment, BMI, and ePWV were associated with recovery (p = 0.030, p = 0.007, p = 0.022).

CONCLUSION

Higher ePWV, a measure of arterial stiffness, was associated with a poor hearing recovery of SSNHL.

Environmental Risk Factors, Protective Factors, and Biomarkers for Hearing Loss: An Umbrella Review

OBJECTIVE

We aimed to investigate the potential environmental risk factors, protective factors, and biomarkers of hearing loss (HL), and establish a hierarchy of evidence.

DATA SOURCES

Embase, PubMed, Cochrane Library, and Web of Science electronic database from inception to June 1, 2023.

REVIEW METHODS

We included meta-analyses of observational studies of associations between HL and environmental risk factors, protective factors, or biomarkers. We calculated summary effect estimates, 95% confidence interval, heterogeneity I2 statistic, 95% prediction interval, small study effects, and excess significance biases.

RESULTS

Of the 9211 articles retrieved, 60 eligible articles were included. The 60 eligible articles identified 47 potential environmental risk and protective factors (N = 4,123,803) and 46 potential biomarkers (N = 173,701). Evidence of association was convincing (class I) for rheumatoid arthritis (RA) and every 1 cm increase in height. Evidence of association was highly suggestive (class II) for human immunodeficiency virus (HIV), diabetes, cumulative noise exposure (CNE), smoking, congenital cytomegalovirus (CMV) infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and alopecia areata (AA).

CONCLUSION

In this umbrella review, RA, every 1 cm increase in height, HIV, diabetes, CNE, smoking, congenital CMV infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and AA were strongly associated with HL.

A Nationwide Population-Based Study for the Recurrence and Comorbidities in Sudden Sensorineural Hearing Loss

OBJECTIVES

The aims of this study were to investigate the cumulative recurrence rate of SSNHL and to determine association between comorbidities and recurrence of SSNHL by comparing patients with and without recurrence.

METHODS

Using the National Health Insurance Claims Database (NHICD) from 2009 to 2020, we conducted a population-based study. We only enrolled patients whose records showed a prescription for steroid and audiometry findings as well as an appropriate diagnostic code. Recurrence of SSNHL was defined as an episode of SSNHL greater than or equal to 3 months after the first episode of SSNHL. We compared the recurrence rate of SSNHL according to age and number of SSNHL recurrences. We also explored comorbidities including autoimmune, metabolic, chronic renal diseases, cancer, and migraine associated with recurrent SSNHL.

RESULTS

A total of 257,123 patients were identified. We found that 6.7% (17,270/257,123) of the patients had at least one recurrence of SSNHL. The recurrence rate increases with the number of recurrences and over time. The incidence per 100,000 people tended to increase with age, and the recurrence rate appeared to decrease with age. We found an increase in the incidence of ankylosing spondylitis (AS) and a decrease in the incidence of type 2 diabetes mellitus (T2DM), myocardial infarction (MI), and hemorrhagic stroke in patients with recurrence.

CONCLUSION

For patients with recurrence or AS, considerable efforts should be made to prevent recurrence. As SSNHL is an emergent otologic condition, when symptoms occur, they should receive immediate treatment. Additional well-designed population-based studies are required to generalize our results.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:1417-1425, 2024.

Sudden Sensorineural Hearing Loss after COVID-19 Vaccination: A Review of the Available Evidence through the Prism of Causality Assessment

Sudden sensorineural hearing loss (SSNHL), a rare audiological condition that accounts for 1% of all cases of sensorineural hearing loss, can cause permanent hearing damage. Soon after the launch of global COVID-19 vaccination campaigns, the World Health Organization released a signal detection about SSNHL cases following administration of various COVID-19 vaccines. Post-marketing studies have been conducted in different countries using either pharmacovigilance or medico-administrative databases to investigate SSNHL as a potential adverse effect of COVID-19 vaccines. Here, we examine the advantages and limitations of each type of post-marketing study available. While pharmacoepidemiological studies highlight the potential association between drug exposure and the event, pharmacovigilance approaches enable causality assessment. The latter objective can only be achieved if an expert evaluation is provided using internationally validated diagnostic criteria. For a rare adverse event such as SSNHL, case information and quantification of hearing loss are mandatory for assessing seriousness, severity, delay onset, differential diagnoses, corrective treatment, recovery, as well as functional sequelae. Appropriate methodology should be adopted depending on whether the target objective is to assess a global or individual risk.

Efficacy of high dose systemic versus combined (systemic and intratympanic) corticosteroid therapy in idiopathic sudden sensorineural hearing loss: A prospective randomized trial and risk factor analysis

The pathophysiology and the proper treatment of idiopathic sudden sensorineural hearing loss (ISSNHL) are an ongoing subject of debate. Locally or systemic administered corticosteroids are the most accepted drugs of treatment in reference to ISSNHL (idiopathic sudden sensorineural hearing loss), however, no strong evidence nor guidelines regarding their effectiveness yet exists. In our prospective, randomized, controlled trial 78 participants were enrolled. Patients were randomly assigned based on the day of admission to two groups according to treatment: group SS (n = 43) received intravenous systemic methylprednisolone alone, and group CT (n = 35) received intratympanic dexamethasone + systemic methylprednisolone. The primary outcome was to compare the hearing outcomes between the treatment groups based on different, widely accepted categories (Siegel, Kanzaki, modified Siegel and PTA4 gain). In consideration of the secondary outcome, we examined the effect of the various risk factors on the hearing improvement. No differences were detected regarding hearing improvement between the two groups, based on any criteria [Siegel's criteria (p = 0.604); Kanzaki's criteria (p = 0.720); modified Siegel's criteria (p = 0.524) and PTA 4 gain (p = 0.569)]. However, several clinical factors such as vertigo (p = 0.039), or cardiovascular comorbidity (p = 0.02) and the severity of initial hearing loss (p = 0.033) were found to bear a significant impact upon the hearing outcome. To the best of our knowledge, this is the first randomized controlled trial comparing high dose systemic and combination corticosteroid therapy in ISSNHL patients. Our findings suggest coexisting cardiovascular comorbidity, vertigo and severity of the initial hearing loss may bear a significantly higher impact upon hearing improvement, than the additional intratympanic steroid administration. The presented trial was registered in the European Union Drug Regulating Authorities Clinical Trials Database (name: Combinated systemic and intratympanic steroid therapy in idiopathic sudden sensorineural hearing loss, No.: 2017-000658-20) and with the ethical approval of The National Institute of Pharmacy and Nutrition (OGYÉI) (protocol No.: 7621, on 2017.02.16.).

The value of gadolinium-enhanced MRI in predicting the development of sudden hearing loss into Ménière's disease

OBJECTIVE

To compare the clinical features of sudden hearing loss (SHL) in patients with and without endolymphatic hydrops (EH), and to investigate the association between SHL with EH and Ménière's disease (MD).

METHODS

The clinical data of 63 SHL patients with first symptoms were evaluated retrospectively. Patients were separated into two groups based on the results of gadolinium-enhanced magnetic resonance imaging: EH and non-EH groups. Independent sample t-test and U-test were used to compare groups for continuous variables, and the chi-squared test, corrected chi-squared test and Bonferroni correction test were used to compare groups for binary and ordinal variables. The binary logistic regression model was utilised for univariate and multivariate analysis of follow-up patient prognosis.

RESULTS

The EH and non-EH groups contained 32 and 31 patients, respectively. The EH group had a higher prevalence of low-tone descending hearing loss. Fifty-one patients were followed for more than 2 years. In the EH group, 11 and 15 patients were diagnosed with sudden sensorineural hearing loss (SSNHL) and MD, respectively, while in the non-EH group, 24 patients were diagnosed with SSNHL and only one with MD. EH, low-tone descending hearing loss and vertigo were risk factors for the diagnosis of MD in a subgroup univariate regression analysis of patients experiencing SHL. EH was found to be a risk factor for the progression of SHL into MD in a multifactor regression analysis.

CONCLUSIONS

Patients with SHL who have EH are more likely to present with low-tone descending hearing loss. EH is a risk factor for the subsequent development of MD.

Hearing Loss after COVID-19 and Non-COVID-19 Vaccination: A Systematic Review

(1) Background: Vaccine safety is an important topic with public health implications on a global scale. The purpose of this study was to systematically review available literature assessing sensorineural hearing loss (SNHL) incidence and severity following both coronavirus disease 2019 (COVID-19) and non-COVID-19 vaccinations, as well as prognosis and outcomes. (2) Methods: This systematic review was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Relevant publications evaluating post-vaccination SNHL were selected from PubMed and Embase, searching from inception to July 2023. (3) Results: From 11 observational studies, the incidence of post-vaccination SNHL was low for both COVID-19 and non-COVID-19 vaccines, ranging from 0.6 to 60.77 per 100,000 person-years, comparable to all-cause SNHL. (4) Conclusions: The incidence rates of SNHL following COVID-19 and non-COVID-19 vaccinations remained reassuringly low. Most patients experienced improved hearing function in the weeks to months following vaccination. This study underscores the importance and safety of vaccinations and encourages ongoing surveillance and detailed reporting of hearing loss cases post-vaccination.

Recovery From Idiopathic Sudden Sensorineural Hearing Loss: Association With Cardiovascular Disease Risk

PURPOSE

The purpose of this study is to investigate the association between cardiovascular disease (CVD) risk factors and idiopathic sudden sensorineural hearing loss (ISSNHL) disease severity and recovery.

METHOD

A retrospective medical chart review was performed on 90 patients (n = 48 men; Mage = 59.8 years, SD = 15.8) evaluated for ISSNHL. Major CVD risk factors (current tobacco smoking, diabetes, total cholesterol ≥ 240 mg/dl or treatment, and hypertension [systolic blood pressure [BP]/diastolic BP ≥ 140/ ≥ 90 mmHg or treatment]) determined two CVD risk groups: lower (no major risk factors) and higher (one or more risk factors). Two pure-tone averages (PTAs) were computed: PTA0.5,1,2 and PTA3,4,6,8. Complete recovery of ISSNHL was defined as PTAinitial - PTAfollow-up ≥ 10 dB. Logistic regression estimated the odds of ISSNHL recovery by CVD risk status adjusting for age, sex, body mass index, noise exposure, and treatment.

RESULTS

Most patients (67.8%) had one or more CVD risk factors. Severity of initial low- and high-frequency hearing loss was similar between CVD risk groups. Recovery was 53.2% for PTA0.5,1,2 and 32.9% for PTA3,4,6,8. With multivariable adjustment, current/former smoking was associated with lower odds of PTA0.5,1,2 recovery (OR = 0.27; 95% CI [0.08, 0.92]). Neither higher CVD risk status nor individual CVD risk factors had a significant association with recovery. For every one-unit increase in Framingham Risk Score, odds of PTA3,4,6,8 recovery were 0.95 times lower (95% CI [0.90, 1.00]) after accounting for age, sex, body mass index, noise exposure, and treatment/time-to-treatment grouping (p = .056).

CONCLUSIONS

The prognosis of low-frequency ISSNHL recovery is worse among current/former smokers than nonsmokers. Other CVD risk factors and aggregate risk are not significantly related to recovery.

Hearing impairment and risk of dementia in The HUNT Study (HUNT4 70+): a Norwegian cohort study

Background

Hearing impairment is strongly associated with future dementia. No studies have reported objectively measured hearing impairment in a cohort with a long period of follow-up (>20 years), and few have reported follow-up over 10 years. Hence, there is a need for high quality studies with sufficient follow-up time and data to account for reverse causality and confounding. We aimed to address this knowledge gap.

Methods

This cohort study used individual participant data from The Trøndelag Health Study (HUNT) in Norway. All current residents aged at least 20 years in the former Norwegian Nord-Trøndelag County were invited to participate in four decennial surveys: HUNT1 (1984-1986), HUNT2 (1995-1997), HUNT3 (2006-2008), and HUNT4 (2017-2019) with individuals aged at least 70 years included in a substudy, known as HUNT4 70+. Here, we report the findings of this substudy. HUNT4 70+ comprised 7135 participants who were assessed for dementia using the Diagnostic and Statistical Manual of Mental Disorders 5 criteria and who had audiometry between 1996 and 1998. The primary objective was to investigate, with gold standard audiometric testing and dementia diagnostic assessment, whether hearing impairment was an independent risk factor for all-cause dementia. The secondary objective was to investigate if a risk also applied to Alzheimer dementia and non-Alzheimer dementia. We analysed the association using Poisson regression and adjusted for confounders. This study is registered with ClinicalTrials.gov (NCT04284384).

Findings

At baseline, 1058 (15%) individuals had acquired hearing impairment with a hearing threshold of at least 25 decibel (dB) and, at follow-up, 1089 (15%) had dementia. In the total group, people with hearing impairment had a relative risk (RR) 1.04 (95% confidence interval (CI) 1.00-1.09) per 10 dB increase in hearing thresholds. For individuals younger than 85 years at follow-up the RR was 1.12 (95% CI 1.05-1.21). Associations between hearing impairment and Alzheimer dementia and non-Alzheimer dementia were similar. There was no association for individuals aged at least 85 years.

Interpretation

We found a moderate association between objectively measured hearing impairment and dementia in the younger age group (<85 years). The findings of no association in the older age group (≥85 years) might be due to the competing risk of death. The present study adds to the literature showing that acquired hearing impairment is a risk for dementias over a period which is too long for reverse causation, and with thorough consideration of confounders. Further research is needed to investigate associations between the different aetiologies of hearing loss and dementia subtypes, and risk differences for sexes.

Funding

The Norwegian National Centre for Ageing and Health with a grant from Health South-East.

Bidirectional Association Between Sudden Sensorineural Hearing Loss and Glaucoma: A Cohort Study

OBJECTIVES

To investigate the bidirectional association between sudden sensorineural hearing loss (SSNHL) and open-angle glaucoma (OAG) over a 12-year follow-up period using nationwide, population-based data.

METHODS

The study was conducted using the National Health Information Database of the National Health Insurance Service (NHIS-NHID), which covered 3.5 million individuals from 2008 to 2019. In Study 1, we evaluated the effect of OAG on SSNHL, and in Study 2, we evaluated the effect of SSNHL on OAG. Participants of the control group were enrolled through "greedy nearest-neighbor" 1:1 propensity score matching.

RESULTS

In Study 1, 26,777 people were included in each group. The hazard ratio (HR) for SSNHL of the OAG group was 1.27 (95% confidence interval [CI], 1.15-1.39). In subgroup analysis, there was significant HR value regarding (old age: 1.17, hyperlipidemia: 1.19). In Study 2, 15,433 people were included in each group. The HR for OAG of the SSNHL group was 1.18 (95% CI, 1.07-1.30). In subgroup analysis, the HRs were significant for old age (2.31), hypertension (1.17), diabetes (1.39), and hyperlipidemia (1.26).

CONCLUSION

Over the 12-year follow-up, we found a bidirectional association between SSNHL and OAG, suggesting a shared pathogenesis.

LEVEL OF EVIDENCE

N/A. Laryngoscope, 133:3169-3177, 2023.

Vertebrobasilar System Laterality and Idiopathic Sudden Sensorineural Hearing Loss

INTRODUCTION

The etiology of idiopathic sudden sensorineural hearing loss (ISSNHL) remains elusive, with vascular compromise as a proposed cause. This study aimed to explore the correlation between the vertebrobasilar vascular system laterality (VBVSL) and ISSNHL laterality.

METHODS

We conducted a retrospective analysis of consecutive patients diagnosed with ISSNHL from 2015 to 2020. The VBVSL pattern was established via magnetic resonance imaging scans by a neuroradiologist. ISSNHL occurring contralaterally to the basilar artery (BA) curvature or ipsilaterally to the dominant vertebral artery (VA) was designated as a "positive match," with all other scenarios classified as a "negative match."

RESULTS

Our study included 191 ISSNHL patients (median age 57 years, 89 males, 93 right ears). The majority of patients did not exhibit a positive match between ISSNHL laterality and the sides of BA curvature or dominant VA (28.8% and 36.6% for BA and VA, respectively). Notably, VA-positive match patients were significantly older than VA-negative match patients (59 vs. 53 years, p = 0.043), with a similar trend observed in BA-positive match compared to BA-negative match (59 vs. 54.5 years, p = 0.057). However, there was no significant difference in any other clinical, audiometric, or outcome factors between the positive and negative match groups.

CONCLUSION

The findings suggest no association between VBVSL and ISSNHL laterality. Furthermore, patients in the positive match group did not exhibit distinct clinical or audiometric features compared to those without a match.

Evaluation of von Willebrand factor and protein/creatinine ratio in idiopathic sudden hearing loss

OBJECTIVE

The objective of this study was to evaluate the levels of von Willebraund Factor (vWF) in plasma and the protein/creatinine ratio in urine in patients with idiopathic sudden acute hearing loss, which we think to be caused by epithelial dysfunction.

MATERIALS-METHODS

Thirty patients with a sudden hearing loss and thirty healthy individuals were included in the study. Before the treatment, blood and urine were collected from the patients and the control group to investigate the levels of the protein/creatinine ratio and the levels of vWF. The test results of the patients group were compared with those of the control group.

RESULTS

We found that the levels of vWF increased in the patient group, which was statistically significant (P<.05). The protein/creatinine ratio in the urine increased in the patient group, but this was not statistically significant (P>.05). In addition, we found that the vWF and urine protein/creatin ratio of the patients who benefited from treatment were lower than those who did not benefit.

CONCLUSIONS

This study showed that sudden sensorineural hearing loss may result from endothelial dysfunction. However, more studies that include more patients are needed in order to support this.

Cardiovascular Risk Factors, Cerebral Small Vessel Disease, and Subsequent Risk of Stroke in Patients with Idiopathic Sudden Sensorineural Hearing Loss: Systematic Review and Meta-Analyses of the Current Literature

Vascular involvement in the pathophysiology of idiopathic sudden sensorineural hearing loss (iSSNHL) has been previously proposed. The objective of this study was to perform a systematic review of the current literature and conduct meta-analyses to evaluate associations between cardiovascular risk factors, cerebral small vessel disease, and subsequent stroke after presentation with iSSNHL. Three systematic literature reviews and meta-analyses were conducted using PubMed, Embase, and CINAHL. All studies investigating associations between iSSNHL and the cardiovascular risk factors: body mass index (BMI), diabetes mellitus, hyperlipidemia, hypertension, medical history of myocardial infarction (MI), smoking, the degree of white matter hyperintensities, and incidence of stroke were included. Adhering to the PRISMA guidelines, two independent reviewers reviewed the articles and assessed risk of bias. The cardiovascular risk factors of abnormal BMI, diabetes, hypertension, total cholesterol, low-density lipoprotein cholesterol, and a medical history of MI were significantly associated with iSSNHL. The adjusted hazard ratio of a higher degree of white matter hyperintensities was 0.70 (95% CI 0.44, 1.12). Patients with iSSNHL showed a higher risk of stroke compared to controls, with hazard ratios ranging from 1.22 up to 4.08. Several cardiovascular risk factors are more frequently present in patients with iSSNHL than in the general population. The degree of white matter hyperintensities does not appear to be increased in patients with iSSNHL, while the risk of stroke following ISSNHL is increased. Prospective studies with larger study populations are needed to confirm the associations between generalized cardiovascular disease and iSSNHL and to assess whether these patients benefit from cardiovascular risk management to prevent future cardiovascular and cerebrovascular disease.

Cardiocerebrovascular risk in sensorineural hearing loss: results from the National Health and Nutrition Examination Survey 2015 to 2018

Objective

This study aims to determine whether the risks of cardiocerebrovascular disease are relevant to sensorineural hearing loss (SNHL) based on a national database.

Methods

A total of 1,321 participants aged from 18 to 69 with complete data including medical history and audiometry from the NHANES database (2015-2018) were analyzed. All included participants had available hearing data and the average thresholds of the hearing data were measured and calculated as low-frequency pure-tone average (LFPTA; 500, 1,000, and 2,000 Hz) and high-frequency pure-tone average (HFPTA; 3,000, 4,000, 6,000, and 8,000 kHz). SNHL was defined as an average pure tone of more than or equal to 20 dB in at least one better ear. Multivariable models to assess the association between cardiocerebrovascular risks and SNHL were used in this study.

Results

The prevalence of stroke was 1.6% in individuals with SNHL and 0.4% in individuals without SNHL (p = 0.023). A higher cardiovascular risk score was observed in SNHL patients compared to participants without SNHL (1.58 vs. 0.90, p < 0.001). Stroke was associated with a 3.67-fold increase in the risk of SNHL (95% CI: 1.12-12.00, p = 0.032) in univariable logistic regression, and the association (OR = 4.22, 95%CI = 1.28-13.93, p = 0.020) remained significant after adjusting for several covariates. Multivariable logistic regression models indicated a positive correlation between cardiovascular risk and SNHL (OR = 1.66, 95% CI = 1.40-1.96, p < 0.001), but no significant relationship was shown with all covariates adjusted. However, significant associations were found between SNHL and both age and sex in both univariable and multivariable logistic regression models.

Conclusion

Our findings suggested that a higher cardiocerebrovascular risk burden was associated with an increased risk of SNHL, and the relationship may be influenced by age and sex. Future longitudinal studies are needed to investigate the mechanistic and pathologic vascular hypothesis of SNHL.

Hearing Loss and Blood Coagulation Disorders: A Review

A relationship between microvascular disorders and sensorineural hearing loss (SNHL) has been widely proposed. The vascular hypothesis, theorized for the onset of sudden SNHL (SSNHL), is among the most acknowledged: a localized acute cochlear damage, of ischemic or haemorrhagic nature, could be considered a causative factor of SSNHL. The aim of this review is to assess (i) the effect on hearing in patients affected by blood coagulation disorders (prothrombotic or haemorrhagic) and (ii) the possible etiopathogenetic mechanisms of the related hearing loss. A PRISMA-compliant review was performed. Medline, Embase, and Cinahl databases were searched from inception to 31 January 2023, and a total of 14 studies have been included in the review. The available data suggest that it is possible to consider clotting disorders as a potential condition at risk for sensorineural hearing loss; in particular, coagulation tests and eventually the assessment of genetic and acquired prothrombotic factors should be recommended in patients with SSNHL. Also, an audiological evaluation should be recommended for patients with blood coagulation disorders presenting cochlear symptoms, especially in those suffering from clotting diseases.

Cerebral Small Vessel Disease in Elderly Patients With Menière's Disease

Background

Menière's disease (MD) is an inner ear disease characterized by vertigo attacks, progressive hearing loss, tinnitus, and the sensation of aural fullness. Although the exact pathophysiology of MD is unknown, endolymphatic hydrops is considered to be its histopathological hallmark. It has been suggested that endolymphatic hydrops results from lowered perfusion pressure due to cardiovascular comorbidity. Cardiovascular risk factors can cause cerebral small vessel disease (CSVD), visible on MRI. The presence of CSVD in turn raises the risk of developing a stroke.

Objectives

This study aimed to compare the presence of CSVD and cardiovascular risk factors in elderly patients with MD to a control cohort.

Methods

Patients diagnosed with MD, aged 50 years and older, were retrospectively reviewed and compared with a control cohort. The primary outcome was the difference in CSVD on MRI imaging, which was assessed by the number of white matter hyperintensities using the ordinal Fazekas scale. The secondary outcome was the presence of brain infarctions on MRI.

Results

A total of 111 patients with MD were compared with a control cohort of 111 patients. No difference in the degree of white matter hyperintensities (P = 0.890) was found between the MD and control cohort. Brain infarctions were seen in 8 of 111 patients with MD and 14 of 111 patients from the control cohort (P = 0.261).

Conclusion

CSVD is not more frequently visible on MRI in elderly patients with MD than in controls. This result does not support hypoperfusion-induced ischemia in the pathophysiology of MD.

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

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

The effectiveness of intratympanic steroid injection in addition to systemic corticosteroids in the treatment of idiopathic sudden sensorineural hearing loss

There is a lot of controversy about the efficacy of intratympanic steroid (ITS) therapy in idiopathic sudden sensorineural hearing loss (ISSHL). ITS are reported to have effect on ISSNHL and ITS with additional systemic therapy are also effective. In the primary treatment of ISSHL, achieving the correct diagnosis rapidly is paramount, as early initial treatment greatly increases the chance of hearing recovery. A retrospective study took place from 2010 to 2017 in the 1st ENT Clinic of Athens. Participants were inward patients that were first examined and diagnosed with ISSNHL in the Emergency Department and afterwards admitted in the clinic. In 2014 our Clinic changed the Treating Protocol of ΙSSNHL. We compared the audiological results of the patients treated with the previous protocol (intravenous steroids) with those treated with the new protocol (concurrent intravenous and intratympanic steroids). The main outcome measure was the hearing threshold before treatment and after completion of therapy. We retrieved from the hospital medical records the following demographic and clinical data: sex, age, date of admission, comorbidities, hearing threshold per frequency on admission and on discharge day and time period between onset of symptoms and initial treatment. We concluded that both intratympanic steroids and systemic steroids alone appear equally effective, however the use of both intratympanic and systemic steroids together is likely superior to either used alone. Intratympanic steroids likely offer additional benefit as a secondary/salvage therapy in patients who fail initial systemic steroid therapy.

Etiological analysis of patients with sudden sensorineural hearing loss: a prospective case-control study

Sudden sensorineural hearing loss (SSNHL) is a multifactorial emergency disease. Until now, the etiology of SSNHL is still unknown. Previous studies regarding the etiology of SSNHL are clinical studies depending on clinical data collection and analysis. Due to the insufficient sample size or various selective bias in clinical studies, the results of these studies may be inaccurate. This prospective case-control study aimed at exploring the possible etiology and risk factors of SSNHL. We enrolled 255 SSNHL patients and 255 sex-, age- and residence-matched non-SSNHL subjects in the control group. Our study shows that there was no significant difference in the prevalence of comorbidities including hypertension and diabetes, as well as the incidence of smoking and drinking habits between the case and control groups (P > 0.05). In addition, the peripheral blood white blood cell count, neutrophil count, platelet-to-lymphocyte ratio (PLR) and fibrinogen level of the case group were significantly higher than those in the control group (P < 0.05). These findings suggest smoking, drinking, hypertension and diabetes may not be related to the onset of SSNHL. However, hypercoagulable state and inner ear vascular microthrombosis related to an elevated fibrinogen level might be the risk factors of the disease. In addition, inflammation play an important role of SSNHL onset.Trial Registration: Chinese Clinical Trial Registry. Registration number: ChiCTR2100048991.

Cardiovascular Risk Factors in Patients With Sudden Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

OBJECTIVE

The interruption of vascular supply to the inner ear is one of several proposed etiologies of sudden sensorineural hearing loss (SSNHL). The increased presence of cardiovascular risk factors may predispose patients to SSNHL through this pathway. This systematic review and meta-analysis studies the presence of cardiovascular risk factors in patients diagnosed with SSNHL.

DATA SOURCES

Databases included PubMed/Medline, OVID, EMBASE, Cochrane, and Web of Science.

REVIEW METHODS

Inclusion criteria included studies featuring SSNHL patients presenting with 1+ cardiovascular risk factors. Exclusion criteria included case reports and studies without outcome measures. Two investigators independently reviewed all manuscripts and performed quality assessments using validated tools.

RESULTS

Of 532 identified abstracts, 27 studies met inclusion criteria (19 case-control, 4 cohorts, 4 case series). Of these, 24 underwent meta-analysis encompassing a total of 77,566 patients (22,620 SSNHL patients, 54,946 matched controls). The mean age was 50.43 years. SSNHL patients were more likely to have concomitant diabetes (odds ratio [OR] 1.61 [95% confidence interval [CI]: 1.31, 1.99; p < .00001]) and hypertension (OR 1.5 [95% CI: 1.16, 1.94; p = .002]). An increased standard mean difference of total cholesterol of 11.09 mg/dL (95% CI; 3.51, 18.67; p = .004) was noted in the SSNHL group compared with the controls. No significant differences in smoking, high-density lipoprotein, triglycerides, or body mass index were detected.

CONCLUSION

Patients presenting with SSNHL have a significantly higher risk of concomitant diabetes, hypertension, and higher total cholesterol in comparison to matched controls. This may indicate a higher cardiovascular risk profile in this population. More prospective and matched cohort studies are needed to understand the role of cardiovascular risk factors in SSNHL.

Cardiovascular Risk Factors and Sudden Sensorineural Hearing Loss: A Case-Control Study

OBJECTIVE

To investigate the role of cardiovascular risk factors (specifically hypertension [HTN], hyperlipidemia/dyslipidemia, diabetes mellitus I and II, and body mass index (BMI) on the development of sudden sensorineural hearing loss (SSNHL).

STUDY DESIGN

Case-control retrospective chart review.

SETTING

A tertiary referral center.

PATIENTS

Patients aged 18 to 85 years who presented to the clinic over a 1-year span (September 17, 2020 to September 17, 2021) for evaluation of sudden sensorineural hearing loss.

MAIN OUTCOME MEASURE

Comparing the prevalence of the different cardiovascular risk factors (CVRFs) in patients with sudden sensorineural hearing loss compared with when compared with non-SSNHL patients at a neurotology clinic.

RESULTS

Two hundred twenty-three patients with SSNHL were compared with age- and gender-matched comparison group to investigate the prevalence of cardiovascular risk factors within each group. There are no statistically significant differences (p > 0.05) in the prevalence of HTN, hyperlipidemia/dyslipidemia, diabetes mellitus I and II, and BMI in patients with sudden sensorineural hearing loss when compared with non-SSNHL patients at a neurotology clinic.

CONCLUSIONS

Despite correlation between CVRF and SSNHL found in some other studies, we did not find a significant correlation between CVRF (diabetes, HTN, dyslipidemia, and high BMI) and SSNHL in our retrospective case control study of patients presenting to a nonacademic tertiary neurotology clinic. Although there may be other factors contributing to the pathogenesis of SSNHL, we have not yet identified these factors.

Evaluation of Disturbances in Hearing, Tinnitus, and Dizziness as Signs of COVID-19 Infection

BACKGROUND

There have been reports and studies indicating audiovestibular disturbances in COVID-19 patients with variations in the percentage of sensorineural hearing loss (SNHL). The purpose of this study is to compare the incidence of newly diagnosed SNHL, sudden idiopathic hearing loss (SIHL), tinnitus, and vestibular disturbances between infected and uninfected patients, as well as to identify population groups at risk.

METHODS

This study used TriNetX to obtain statistics on COVID-19 (+) and COVID-19 (-) patients from 61 healthcare organizations. Propensity score with 1:1 matching was used to control confounding variables. This study evaluated the relative risk of developing audiovestibular disturbances up to 1 month after a COVID-19 test and further investigated the incidence in COVID-19 (+) subset groups.

RESULTS

Between COVID-19 (+) and COVID-19 (-) patients who had an audiogram, there was no statistically significant difference in SNHL or SIHL (SNHL: relative risk [RR] = 0.69, 95% confidence interval [CI] = 0.46-1.04; SIHL: RR = 1.00, 95% CI = 0.42-2.40). Race/ethnicity or specified comorbidity did not affect the incidence of SNHL or SIHL. There was a statistically significant difference in tinnitus and vestibular disturbances between the COVID-19 (+) and the COVID-19 (-) groups (RR = 1.29, 95% CI = 1.01-1.66; RR = 2.33, 95% CI = 2.19-2.48).

CONCLUSION

New onset hearing loss is not more common in patients with a positive COVID-19 test than those with a negative COVID-19 test. Audiologic evaluation is needed to verify reported hearing disturbances. Although statistically significant in specific population groups, tinnitus and vestibular disturbances may not be clinically significant due to the low incidence.

Cardiovascular Risk and Sudden Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

OBJECTIVES/HYPOTHESIS

It was previously suggested that patients with idiopathic sudden sensorineural hearing loss (ISSNHL) have a higher risk of cardiovascular disease. The aim of this study is to determine if ISSNHL patients have an increased cardiovascular risk by means of a systematic review and meta-analysis.

METHODS

A systematic literature review was performed using PubMed, Embase, Cochrane Libraries and Web of Science. Studies with a clear definition of ISSNHL, investigating an association between traditional vascular risk factors and ISSNHL were included. Adhering to Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines, two reviewers extracted the data, assessed the risk of bias and performed the analysis of the collected evidence.

RESULTS

Nineteen case-control studies and two cohort studies were included (102,292 patients). Individual studies argued for higher prevalence of hypercholesterolemia, diabetes mellitus (DM) and higher blood pressure (HBP) in ISSNHL patients with a range of odds ratios (ORs) from 1.03 to 19. Pooled analysis of adjusted ORs revealed a significantly increased risk of ISSNHL for patients with hypertriglyceridemia (OR 1.54; 95% confidence interval [CI] 1.18-2.02) and high levels of total cholesterol (TC) (OR 2.09; 95% CI 1.52-2.87 after sensitivity analysis), but not for HBP, DM, or high levels of low- and high-density lipoproteins.

CONCLUSION

An association between higher vascular risk profile and ISSNHL seems apparent in high levels of triglycerides (TG) and TC, but more studies are needed to confirm this hypothesis due to the high levels of data heterogeneity in the literature.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:15-24, 2023.

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

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

Time from sudden sensory neural hearing loss to treatment as a prognostic factor

Introduction

The widely accepted treatment for sudden sensorineural hearing loss (SSNHL) is corticosteroid treatment (oral or intratympanic). The main goal of this work is to define the significance of the time between symptom onset and treatment initiation, as well as other prognostic factors, for hearing improvement.

Methods

This retrospective study included 666 patients treated for SSNHL. Demographic data, audiometry, treatment method, time since symptom onset, and associated symptoms were recorded for each patient. The patients were divided into five groups according to the treatment initiation time-half a week, one week, 2 weeks, 3 weeks, or 4 weeks and over-after symptom onset. The degree of improvement was assessed by comparing the audiometry at the beginning and the end of the treatment.

Results

The average period of hearing loss from symptom onset to treatment initiation was 10.8 days. Significant differences were found between the groups of half a week, one week, and 2 weeks and the groups of 3 weeks and 4 weeks and over (each separately, p < 0.001). No difference was found between the half-week, one-week, and two-week groups, nor was there a difference between the three-week and four-week-and-over groups. A correlation was found between the treatment initiation time in days and the degree of improvement in hearing for both speech recognition threshold (SRT) and discrimination, R = 0.26 p < 0.001 and R = 0.17 p < 0.001, respectively. No correlation was found for gender, age of the patients, comorbidities, or associated symptoms.

Conclusion

The threshold for treatment initiation time is up to 2 weeks, after which the amplitude of hearing improvement decreases significantly. The other prognostic factors measured were not found to be statistically significant predictors.

Cardiovascular risk factors among patients with acute unilateral inner ear hypofunction: A case-control study

Objectives

To assess the prevalence of cardiovascular risk factors (CVRFs) and their impact on acute unilateral inner ear hypofunction (AUIEH), including acute unilateral peripheral vestibulopathy (AUPVP), sudden sensorineural hearing loss (SSNHL) and acute unilateral audiovestibular hypofunction (AUAVH).

Methods

One hundred and twenty-five patients consecutively diagnosed with AUPVP, SSNHL or AUAVH and 250 sex- and age-matched controls were included. Cases presented a mean age of 58.6 ± 14.7 years and included 59 women and 66 men. The correlation between CVRFs (high blood pressure [HBP], diabetes mellitus [DM], dyslipidemia [DLP], cardiocerebrovascular disease [CCVD]) and AUIEH was assessed by multivariate conditional logistic regression analysis.

Results

A higher prevalence of CVRFs was identified in patients than in controls (30 individuals with DM, 53 with HBP, 45 with DLP and 14 with a previous history of CCVD, p < .05). A significantly elevated risk of AUIEH was found in patients with two or more CVRFs (adjusted odds ratio [OR] 5.11; 95% CI 2.23-11.70). Previous CCVD individually predicted AUIEH (OR 8.41; 95% CI 2.36-29.88). Subgroup analysis showed the same tendency for AUPVP and SSNHL.

Conclusion

Acute unilateral inner ear hypofunction patients presented significantly more CVRFs than controls, and the presence of two or more CVRFs was associated with AUIEH. Future studies evaluating vascular risk in AUIEH may include AUPVP and SSNHL patients from the same source population to better characterize risk profiles that can indicate a vascular origin.

Level of Evidence

3b.

[Multifactorial analysis of the degree of hearing loss and outcome in patients with sudden hearing loss]

Objective:To investigate the relationship between the severity and curative effect of hearing loss and clinical indicators in patients with sudden hearing loss （SHL）. Methods:The Spearman correlation coefficient was used to analyze the correlation between the efficacy of SHL and clinical indicators.A total of two hundred and seventy-three patients with SHL were selected and divided into three quantile groups according to the average hearing threshold of the the involved ear frequency of the first pure tone audiometry at admission. Univariate and multivariate ordered logistic regression were used to evaluate the relationship between initial hearing level and clinical indicators of SHL patients. The Spearman correlation coefficient was used to analyze the correlation between efficacy of SHL and clinical indicators. Results:Compared with patients with lower hearing loss （≤50 dB HL），patients with higher hearing loss （>50 dB HL） had higher Neutrophil, Monocyte, Triglycerides, Hemoglobin, Fibrinogen, Glucose, Neutrophil/high-density lipoprotein cholesterol ratio （NHR）, Monocyte/high-density lipoprotein cholesterol ratio, Monocyte/lymphocyte cell ratio, age, dizziness, and lower Platelet/ lymphocyte cell ratio and High-density lipoprotein cholesterol, and poor final hearing threshold.Multivariate logistic regression showed that NHR and age were independent risk factors for initial hearing loss in SHL patients.And the NHR, Neutrophil/lymphocyte cell ratio （NLR）, course of disease, type of hearing curve, and final hearing threshold were significantly negatively correlated with curative effect. Conclusion:SHL patients with higher NHR and NLR values, the longer time from onset to visit, and the more severe hearing loss had worse efficacy.However, SHL patients with higher NHR and age values had greater initial hearing loss,the degree of hearing loss and curative effect are different in SHL patients with different types of hearing threshold curve and age.

Metformin Reduces the Incidence of Sensorineural Hearing Loss in Patients With Type 2 Diabetes Mellitus: A Retrospective Chart Review

Introduction and objectives

Acquired sensorineural hearing loss (SNHL) has become a critical societal issue in recent years. SNHL is considered a risk factor for type 2 diabetes mellitus (T2DM). Metformin is commonly used to treat T2DM. However, its effects on SNHL have not been reported yet. Hence, this study aimed to evaluate the association between the use of metformin and SNHL incidence.

Patients and methods

In this retrospective matched-cohort study, the medical records of 1219 patients with T2DM aged >18 years from our hospital’s inpatient database from January 1, 2012, to December 31, 2019, were examined, and matched cohorts were generated (76 patients receiving metformin and 76 not receiving metformin). A multivariable logistic regression analysis was performed to investigate the factors influencing the incidence of SNHL.

Results

After adjustment by propensity matching, multivariable logistic regression analysis revealed that the non-use of metformin increased the risk of developing SNHL (odds ratio, 0.26; 95% confidence interval, 0.07-0.93; p = 0.03).

Conclusions

This study demonstrated an association between the use of metformin and a reduced incidence of SNHL among patients with T2DM.

Diagnostic value and prognostic significance of MRI findings in sudden sensorineural hearing loss

Purpose

Materials and Methods

Results

Conclusion

Lay Summary

Level of Evidence

Evaluation of the Recovery of Idiopathic Sudden Sensorineural Hearing Loss Based on Estimated Hearing Disorders

Various prognostic factors for idiopathic sudden sensorineural hearing loss (SSNHL) have been reported. Hearing loss directly derived from idiopathic SSNHL is important for understanding underlying pathogenesis and outcomes. We assessed the usefulness of evaluating hearing loss and recovery of idiopathic SSNHL on the basis of estimated hearing loss. The study included 115 patients whose characteristics and outcomes of hearing loss were investigated. The effects of vertigo/dizziness and age on hearing thresholds before/after treatment, nonaffected ear threshold, estimated hearing loss, improvement of hearing loss, and estimated remaining hearing loss were investigated. Vertigo/dizziness was a significant prognostic factor for hearing. In vertigo/dizziness patients, significantly more severe hearing loss and poorer improvement of hearing loss were observed above 500 Hz and below 1000 Hz, respectively. Severe hearing disorder remained at all frequencies. Conversely, post-treatment thresholds were significantly higher in the older population (≥65 years), although no differences in pretreatment thresholds were observed between the younger (≤64 years) and older populations. However, on the basis of nonaffected ear thresholds, previously existing hearing loss could have influenced the outcome. Thus, comparison of hearing outcomes between affected and nonaffected ears is essential for understanding hearing loss and outcomes in idiopathic SSNHL cases with existing hearing disorder.

Predictive factors of acute sensorineural hearing loss in adult Japanese patients for clinical application by primary care doctors: a cross-sectional study

Background

Several methods are used for hearing loss screening; however, their benefits are uncertain. In this study, we aimed to determine the predictive factors of acute sensorineural hearing loss for clinical application by primary care doctors.

Methods

This retrospective, cross-sectional study included 365 patients with acute sensorineural hearing loss without prior therapy. The patients’ clinical data, demographic information, and medical histories were obtained, and they were asked about comorbidities. In addition, we assessed lifestyle factors such as stress level, alcohol consumption, marital status, and socioeconomic level. Logistic regression analysis was performed to investigate the diagnostic predictive ability of the selected factors associated with acute sensorineural hearing loss. The hearing levels of all patients were evaluated using pure tone audiometry.

Results

We identified significant predictive factors for acute sensorineural hearing loss. The absence of hyperacusis was a predictive factor for sudden sensorineural hearing loss. Younger age, female sex, and marital status were predictive factors for acute low-tone hearing loss. High body mass index, high socioeconomic level, low alcohol consumption, high stress level, hyperacusis, and vertigo/dizziness were predictive factors for Ménière’s disease. High body mass index and ear fullness were predictive factors for perilymph fistula. Low stress level was a predictive factor for acoustic tumours.

Conclusions

Our findings can be used to distinguish between the types of acute sensorineural hearing loss. Symptoms, physical status, and lifestyle factors identified during this study are useful markers for predicting acute sensorineural hearing loss occurrence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-022-01830-8.

Hearing Impairment in Stroke Patients- Findings from a Pilot Study Conducted in India

Auditory processing difficulties and hearing loss have been reported among stroke survivors, but is largely neglected. Post-stroke hearing impairment may affect communication between stroke survivors and healthcare professionals, thereby restricting rehabilitation and long-term patient outcome. In this prospective pilot study, we sought to determine the prevalence and pattern of hearing loss in stroke patients when compared to age and sex matched controls. 50 consecutive patients with first-ever stroke, both hemorrhagic and ischemic, and a comparison cohort of 50 age and sex matched controls were assessed. Pure Tone Audiogram was performed in all patients within 15 days of stroke onset and mean hearing loss was determined. Mean audiometric threshold was significantly higher in both ears in stroke patients (mean 44.0 ± 12.1 dB) when compared to the control subjects (36.1 ± 11.4 dB; p = 0.001). After adjusting for Diabetes mellitus and hypertension, sensorineural hearing loss was more common and severe in stroke compared to controls (p < 0.005). Most of the strokes were ischemic and involved middle cerebral artery territory. A modest correlation between hearing threshold and stroke severity in both ears was seen (mean B 0.775, R² 0.54, CI 0.122-1.427, p = 0.020). Our pilot study shows significant hearing impairment in patients with stroke, compared to age and sex matched controls with similar prevalence of cardiovascular risk factors, interestingly seen in a predominantly anterior circulation stroke population. Undetected hearing loss may impact post stroke functional recovery. Hence, current rehabilitation guidelines should include auditory screening in all patients of stroke for detection of hearing loss.

Prognostic Factors Influencing the Tinnitus Improvement After Idiopathic Sudden Sensorineural Hearing Loss Treatment

PURPOSE

Logistic regression analysis was used to explore the factors that influence tinnitus improvement after idiopathic sudden sensorineural hearing loss (ISSNHL) treatment.

MATERIALS AND METHODS

In this retrospective study, 137 ISSNHL patients with tinnitus were recruited at the Sun Yatsen Memorial Hospital of Sun Yat-sen University, China. They underwent audiological examinations, vestibular assessments, tinnitus examinations, a Tinnitus Handicap Inventory (THI) assessment and ISSNHL treatments. Logistic regression analysis was performed to investigate factors that affected tinnitus improvement.

RESULTS

Participants were divided into an effective group (73 patients) and noneffective group (64 patients) according to THI scores before and after treatment. The effective group had better averaged hearing threshold than the noneffective group (effective group vs. noneffective group: 74.47 vs. 87.66 dB HL; t = 3.03, p < 0.05). Additionally, before intervention there were significant difference in profound audiogram configuration (effective group vs. noneffective group: 17.81% vs. 46.88%, x2 = 23.63; p < 0.001), mid tinnitus pitch (effective group vs. noneffective group: 19.18% vs. 35.94%, x2 = 6.58; p = 0.037) and mean THI scores (effective group vs. noneffective group: 57.07 ± 22.27 vs. 36.78 ± 24.41, t = -5.09, p < 0.001) between the effective and noneffective tinnitus groups. Logistic regression analysis showed that audiogram configurations (profound audiogram: OR = 0.10, 95% CI 0.01-0.72, p = 0.022), tinnitus pitch (mid tinnitus pitch: OR = 0.16, 95% CI 0.05-0.57, p = 0.004) and THI scores (OR = 1.05, 95% CI 1.03-1.07, p < 0.001) were independent factors associated with tinnitus improvement.

CONCLUSION

Audiogram configuration, tinnitus pitch, and THI scores before intervention appear to be predictive of the effectiveness of acute tinnitus improvement following ISSNHL treatment.

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.

Prediction of hearing recovery in unilateral sudden sensorineural hearing loss using artificial intelligence

Despite the significance of predicting the prognosis of idiopathic sudden sensorineural hearing loss (ISSNHL), no predictive models have been established. This study used artificial intelligence to develop prognosis models to predict recovery from ISSNHL. We retrospectively reviewed the medical data of 453 patients with ISSNHL (men, 220; women, 233; mean age, 50.3 years) who underwent treatment at a tertiary hospital between January 2021 and December 2019 and were followed up after 1 month. According to Siegel's criteria, 203 patients recovered in 1 month. Demographic characteristics, clinical and laboratory data, and pure-tone audiometry were analyzed. Logistic regression (baseline), a support vector machine, extreme gradient boosting, a light gradient boosting machine, and multilayer perceptron were used. The outcomes were the area under the receiver operating characteristic curve (AUROC) primarily, area under the precision-recall curve, Brier score, balanced accuracy, and F1 score. The light gradient boosting machine model had the best AUROC and balanced accuracy. Together with multilayer perceptron, it was also significantly superior to logistic regression in terms of AUROC. Using the SHapley Additive exPlanation method, we found that the initial audiogram shape is the most important prognostic factor. Machine/deep learning methods were successfully established to predict the prognosis of ISSNHL.

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

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

Sudden Sensorineural Hearing Loss May Increase the Risk of Retinal Vein Occlusion: A Nationwide Cohort Study

Sudden sensorineural hearing loss (SSNHL) is thought to be a vascular disease. Retinal vein occlusion (RVO) is an also common ophthalmic vascular disease. Thus, we investigated the potential relationship between these using a retrospective nationwide cohort dataset. We compared 49,584 subjects in the SSNHL and the comparison (non-SSNHL) groups using patients randomly selected via propensity-score matching. We calculated the incidence, survival rate, and hazards ratio (HR) using log-rank test, and Cox proportional hazards regression models. This study examined a total of 375,490.4 person-years in the SSNHL group and 373,698.2 person-years in the comparison group. We found that 673 patients in the SSNHL group (1.8 cases per 1000 person-years) and 592 in the comparison group (1.6 cases per 1000 person-years) developed RVO during the 8-year follow-up period. The adjusted HR of RVO was 1.13 (95% confidence interval [CI] 1.01–1.26). The adjusted HR of developing RVO in SSNHL was the greatest in elderly patients (adjusted HR, 1.21; 95% CI, 1.01–1.46) and male patients (adjusted HR, 1.18; 95% CI, 1.03–1.34). Our findings suggest that clinicians should remain vigilant of the possibility of RVO development in SSNHL patients, specifically elderly male patients.

Accelerated Long-Term Hearing Loss Progression After Recovery From Idiopathic Sudden Sensorineural Hearing Loss

Background and Introduction: Idiopathic sudden sensorineural hearing loss (ISSNHL) is characterized by rapid onset, typically unilateral presentation, and variable recovery. This case-control observational study aimed to improve patient counseling by objectively characterizing long-term hearing loss progression following ISSNHL, using sequential audiometry in the largest-to-date cohort of patients with ISSNHL.

Methods: Patients diagnosed with ISSNHL at a tertiary referral hospital from 1994 through 2018 with sequential audiometry were studied. Case controls with sensorineural hearing loss (SNHL) were matched by age, sex, baseline hearing status, and frequency of sequential audiometry. Hearing loss progression was quantified using Kaplan–Meier (K–M) analysis to account for variable follow-up duration. A subgroup analysis was performed by age, sex, preexisting comorbidities, ISSNHL-associated symptoms, ISSNHL treatment, and degree of post-ISSNHL hearing recovery.

Results: A total of 660 patients were identified with ISSNHL. In patients with post-ISSNHL recovery to good hearing [pure tone average (PTA) <30 dB and word recognition score (WRS) > 70%], median time to progression to non-serviceable (PTA > 50 dB or WRS <50%) SNHL was 16.4 years. In patients with incomplete post-ISSNHL hearing recovery, contralateral ears were also at significantly higher risk of SNHL progression over the following 12-year period. Male sex was associated with increased risk of SNHL progression [odds ratio (OR) 3.45 male vs. female] at 5-year follow up. No other subgroup factors influenced the likelihood of SNHL progression.

Discussion and Conclusion: Patients should be counseled on continued risk to long-term hearing after stabilization of hearing post-ISSNHL, with particular emphasis on greater risk to the contralateral ear in those with incomplete ipsilateral recovery.

Fasudil prevents neomycin-induced hair cell damage by inhibiting autophagy through the miR-489/NDP52 signaling pathway in HEI-OC1 cells

Hearing loss is a common sensory disorder that is mainly caused by the loss of hair cells (HCs). Drug-induced deafness, for which there is currently no effective treatment, is mainly caused by the inappropriate use of aminoglycoside antibiotics. Fasudil (Fas), a novel isoquinoline sulfonamide derivative, has exhibited antioxidant abilities in a number of previous studies. The aim of the present study was to investigate the potential effects of Fas against neomycin (Neo)-induced hair cell damage and elucidate the underlying mechanism. Flow cytometry and western blot analysis were used to detect the effects of Fas on cell apoptosis and to determine the expression levels of autophagy-related proteins, LC3B and Beclin 1, induced by Neo. Mitochondrial membrane potential and reactive oxygen species (ROS) levels were detected using fluorescent probes. The effect of Fas on Neo-induced hair cell injury marker, GFP-LC3B, was also examined using the immunofluorescence technique. Fas was found to inhibit Neo-induced mitochondrial autophagy and mitochondrial membrane potential decline, in addition to reducing ROS levels and cell apoptosis caused by Neo treatment. However, Fas failed to inhibit the Neo-induced these above changes in cells with NDP52 overexpression. The putative binding sites of microRNA (miR)-489 on the 3'-untranslated region of nuclear dot protein 52 (NDP52) were predicted using the TargetScan 7.0 online tool, and this association was further verified using a dual-luciferase reporter assay. Moreover, the expression of miR-489 negatively regulated the expression of NDP52. Fas and miR-489 mimic inhibited the Neo-induced mitochondrial autophagy and mitochondrial membrane potential decline, in addition to reducing ROS levels and cell apoptosis. Knockdown of miR-489 expression using a miR-489 inhibitor blocked the inhibitory effects of Fas on the mitochondrial membrane potential, cell apoptosis and ROS production. Therefore, Fas may upregulate the expression of miR-489 to negatively regulate the expression of NDP52 at the post-transcriptional level, which in turn inhibits the activation of mitophagy and cell injury induced by Neo. Thus, Fas may act as a novel therapeutic option in the clinical treatment of hearing loss in the future.

Association of Acute Upper Respiratory Tract Infections with Sudden Sensorineural Hearing Loss: A Case-Crossover, Nationwide, Population-Based Cohort Study

The etiology of sudden sensorineural hearing loss (SSNHL) has been unclear until now. Understanding its potential etiology is crucial for the development of preventive medicine. In this study, we investigated the association between acute upper respiratory tract infections (URIs) and SSNHL risk. We conducted a case-crossover study by using the longitudinal health insurance database derived from the National Health Insurance Research Database in Taiwan. Individual acute URI between the case and control periods was reviewed. Multivariable conditional logistic regression models were used to estimate the adjusted odds ratios (aORs) of SSNHL risk associated with acute URIs after adjustments for potential confounders. In total, 1131 patients with SSNHL between 2010 and 2013 fulfilled our inclusion criteria and were included. The aOR (95% confidence interval [CI]) for SSNHL was 1.57 (1.20-2.05) in relation to acute URIs one month before the index date. Moreover, the aORs (95% CIs) of the female and young to middle-aged (≤65 years) populations were 1.63 (1.13-2.36) and 1.76 (1.29-2.40), respectively. In addition, the association between SSNHL and acute URIs was decreased over time. The aOR for SSNHL was 1.25 (1.01-1.56) in relation to acute URIs three months before the index date. Acute URIs increase SSNHL risk and are a potential risk factor for SSNHL. The establishment of a feasible health policy for the prevention of acute URIs is crucial for SSNHL prevention, particularly in female, and young to middle-aged populations.

Sudden Sensorineural Hearing Loss and Metabolic Syndrome: A Systematic Review and Meta-analysis

OBJECTIVE

The objective of this systematic review and meta-analysis is to examine the association between sudden sensorineural hearing loss (SSNHL) and risk of metabolic syndrome (MetS), and the association between MetS and prognosis of SSNHL.

DATABASES REVIEWED

We systematically searched MEDLINE, Embase, and Cochrane Central Register electronic databases from their dates of conception to February 4, 2020.

METHODS

We included observational studies analyzing 1) the prevalence of MetS among SSNHL patients, or 2) the prognosis of SSNHL patients in MetS patients. A standardized form was completed in duplicate extracting data on study characteristics, participant demographics, and SSNHL outcome or recovery measures. Random-effects meta-analyses were performed pooling odds ratios using the generic inverse method. Risk of bias was assessed using the Newcastle Ottawa Scale.

RESULTS

Three studies examining the prevalence of MetS among patients with SSNHL (11,890 total participants; 3,034 SSNHL participants) yielded a significantly increased risk of MetS among SSNHL, with a pooled odds ratio of 1.88 (95% CI, 1.01-3.50). Three studies examining the association of SSNHL prognosis in patients with MetS (608 SSNHL participants, 234 concomitant SSNHL, and MetS participants) demonstrated that SSNHL patients with MetS were significantly more likely to have poorer recovery compared to SSNHL patients without MetS (pooled odds ratio 2.77; 95% CI, 2.33-3.28).

CONCLUSION

Our findings suggest an association between prevalence of MetS and SSNHL, as well as poorer prognosis of SSNHL in patients with concomitant MetS.

Risk factors associated with idiopathic sudden sensorineural hearing loss in pregnant South Korean women: a nationwide population-based study

OBJECTIVE

Sudden sensorineural hearing loss (SSNHL) is rare in pregnancy and can be attributed to pregnancy-induced changes in hormone levels that increase thrombogenic risk and alter cochlear microcirculation with consequent development of sudden deafness. The study aimed to analyze the risk factors associated with SSNHL in pregnant South Korean.

METHODS

A retrospective study of the incidence and risk factors associated with SSNHL before pregnancy enrolled 401,470 Korean women who delivered between January 2010 and December 2014. All participants underwent a pre-pregnancy national health screening examination through the National Health Insurance Corporation. We investigated the risk factors in 459 pregnant women with sudden sensorineural hearing loss and in 401,011 pregnant women without SSNHL through the pre-pregnancy national health screening examination and adverse perinatal outcome.

RESULTS

No statistically significant intergroup differences were observed in the maternal age, parity, method of delivery, gestational age at delivery, body mass index, blood pressure, as well as fasting blood glucose and cholesterol levels. After adjusting for maternal age, the pre-pregnancy body mass index was associated with an increased risk of sensorineural hearing loss in pregnancy (adjusted odds ratio 1.52, 95% confidence interval 1.04-2.22). The sensorineural hearing loss did not increase the risk for gestational hypertension, preterm birth (<37 weeks' gestation), small- and large-for-gestational-age infants, postpartum hemorrhage, placenta previa, and placental abruption.

CONCLUSION

SSNHL can occur throughout pregnancy and is associated with maternal pre-pregnancy obesity. Notably, it does not increase risks during delivery or cause adverse perinatal outcomes.

Hearing impairment and diverse health outcomes : An umbrella review of meta-analyses of observational studies

BACKGROUND

Globally, it is estimated that approximately 1.3 billion people live with some form of hearing impairment. Major causes of hearing loss include infection/disease, age-related factors, and occupational factors. Numerous systematic reviews and meta-analyses have attempted to synthesise literature on these topics. To date there has not been a systematic evaluation of the relationships between hearing impairment and diverse physical, mental, and social outcomes.

OBJECTIVE

We performed an umbrella review of systematic reviews of observational studies with meta-analyses for any physical disease, biomarkers of disease, mental health or cognitive outcomes, and/or modifiable risk factors associated with hearing impairment.

METHODS

For each meta-analytic association, random effects summary effect size, 95% confidence intervals, heterogeneity, evidence for small-study effect, excess significance bias and 95% prediction intervals were calculated, and risk of bias was assessed via the AMSTAR2 tool. These were used to grade significant evidence (p < 0.05) from I to IV, using the recommendations from the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

From 3747 studies, 21 were included covering 54 outcomes. Overall, 44/54 outcomes (82%) yielded significant results. Of the highest quality evidence, age-related hearing loss and non-specific hearing impairment were negatively associated with several types of cognitive impairments; pediatric bilateral hearing loss was negatively associated with quality of life, sensorineural hearing loss was positively associated with rheumatoid arthritis and tinnitus was positively associated with temporomandibular disorders.

CONCLUSION AND RELEVANCE

Results show moderate quality evidence for associations between several types of hearing impairments and cognitive difficulties, quality of life and systemic diseases such as rheumatoid arthritis. Practitioners and public health policies should note these findings when developing relevant healthcare policies.

Sensorineural hearing loss and risk of stroke: a systematic review and meta-analysis

The aim of this systematic review and meta-analysis study was to clarify the effects of sensorineural hearing loss (SNHL) on the incidence of stroke. In line with this, PubMed, Scopus, Web of Science, and ScienceDirect databases were searched using related keywords and MeSH terms from inception to March 1, 2020. Out of the 1961 initial records, eight cohort studies comprising 4,564,202 participants were included, and their qualities were assessed using the Newcastle-Ottawa Scale (NOS). Then, the random-effects model was used to pool HR (95% CI) for risk of stroke; and heterogeneity was presented with I² index. Subgroup analysis and publication bias tests were performed, and the pooled HR (95% CI) of stroke in SNHL was estimated as 1.31 (1.08, 1.53) for the unadjusted model and 1.33 (1.18, 1.49) for the adjusted model. Subgroup analysis indicates a significantly higher risk of stroke in patients with sudden SNHL (SSNHL) in comparison to age-related HL (ARHL) both in the unadjusted model, [HR = 1.46; 95% CI (1.08, 1.63)] versus [HR = 1.14; 95% CI (0.64, 1.65)], and in the adjusted model, [HR = 1.44; 95% CI (1.15, 1.74)] versus [HR = 1.29; 95% CI (1.24, 1.34)]. Our study showed that patients with SNHL face a higher risk of stroke than those without SNHL. It is necessary to perform hematologic and neurological examinations to help clinicians detect patients who are potentially at risk for stroke.

The Clinical Value of Periventricular White Matter Hyperintensity on MRI in Sudden Sensorineural Hearing Loss

OBJECTIVES

To assess the clinical value of periventricular white matter hyperintensity (PWMH) found on brain magnetic resonance imaging (MRI) in patients with sudden sensorineural hearing loss (SSNHL).

METHODS

In this prospective study, 115 patients who were diagnosed with SSNHL aged between 55 and 75 years were analyzed. All subjects underwent brain MRI and were divided into a PWMH and control groups, depending on the presence of PWMH on MRI. PWMH was subdivided into 3 groups according to severity. Pure-tone average results and hearing gain were compared between the 2 groups before treatment and 2 months after treatment. Hearing improvement was assessed using Sigel's criteria.

RESULTS

A total of 106 patients (43 in the PWMH group and 63 in the control group) finally completed the 2-month follow-up. Average hearing gain in the PWMH group was significantly higher than in the control group (34.8 ± 20.3 and 25.9 ± 20.3, respectively, P = .029). PWMH score 1 showed significantly better hearing levels and hearing gain compared to PWMH score 3 and the control group. Multivariate analysis revealed that younger age, better initial hearing level, and the presence of PVWM score 1 were associated with good recovery.

CONCLUSIONS

The presence of PWMH score 1 on brain MRI in patients with SSNHL was associated with better treatment response and was a good prognostic factor in a multivariate analysis while the hearing recovery in more severe PWMH (scores 2, 3) was not different from the control group.

Autonomic Nervous Function in Patients with Sudden Sensorineural Hearing Loss and Its Association with Prognosis and Disease Severity

INTRODUCTION

Vascular disorder is considered one of the main mechanisms of sudden sensorineural hearing loss (SSNHL) due to the anatomy of the inner ear. One factor that can contribute to vascular disorder is impairment in the autonomic nervous system. This study aims to investigate autonomic function in patients with SSNHL and its association with prognosis and disease severity from January 2018 to October 2019.

METHODS

We conducted a cross-sectional study involving 40 healthy controls and 55 subjects with SSNHL. We compared the autonomic function of controls and patients using heart rate variability (HRV). SSNHL patients were divided into improvement and no-improvement groups and into mild and severe groups according to pure-tone audiometry results.

RESULTS

The SSNHL group had significantly decreased total power (TP), low frequency (LF), and high frequency (HF) compared to the control group. However, there were no significant differences between the mild and severe groups. In the no-improvement group, LF was significantly higher and normalized HF was significantly lower than in the improvement group. According to a multiple logistic regression analysis, age and LF were significantly correlated with improvement.

CONCLUSION

This is the first study to evaluate the significance of HRV in patients with SSNHL, according to prognosis and disease severity. Further studies about the relationship between autonomic nervous system and SSNHL with larger sample size and prospective design are needed.