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

Frequency and Patterns of Hearing Dysfunction in Patients Treated with Teprotumumab

PURPOSE

To better characterize the frequency and patterns of hearing dysfunction in patients who have received teprotumumab to treat thyroid eye disease.

DESIGN

Noncomparative case series.

PARTICIPANTS

Patients who underwent audiology testing before and after completion of teprotumumab infusions.

METHODS

A review of patients who underwent audiology testing before and after completion of teprotumumab infusions was carried out. Additional audiogram testing during treatment was included when available. Hearing function was analyzed using audiogram data measuring threshold hearing levels at specific frequencies. Basic demographic data as well as information regarding otologic symptoms also were obtained and analyzed.

MAIN OUTCOME MEASURES

Hearing loss demonstrated by a significant change in decibel hearing thresholds or that meets criteria for ototoxicity.

RESULTS

Twenty-two patients (44 ears) were included in the study, with baseline and most recent audiology testing after treatment ranging from 84 days before to 496 days after treatment. Fifteen patients (30 ears) also underwent testing during treatment starting after the second infusion up until the day of, but before, the eighth infusion. Hearing loss after treatment met criteria for ototoxicity in 17 of the 44 ears (38.6%), with 11 of the 22 patients (50.0%) meeting criteria in at least 1 ear. The pure-tone average decibel hearing levels (HLs) across all 44 ears demonstrated hearing loss after treatment (P = 0.0029), specifically at high (P = 0.0008) and middle frequencies (P = 0.0042), but not at low frequencies (P = 0.8344). Patients who were older also were more likely to experience hearing loss after treatment (P = 0.0048).

CONCLUSIONS

Audiometric data demonstrate that teprotumumab influences hearing function, most significantly at higher frequencies and in older patients. Audiometric testing is critical for counseling patients regarding teprotumumab treatment. A protocol for monitoring hearing during treatment is needed to detect and manage hearing changes associated with teprotumumab use.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

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.

Characteristics and prognostic analysis of simultaneous bilateral sudden sensorineural hearing loss

Objective

To evaluate the clinical characteristics of simultaneous bilateral sudden sensorineural hearing loss (Si-BSSNHL) as well as its prognostic factors.

Methods

Patients with Si-BSSNHL who were admitted to the Department of Otology Medicine between December 2018 and December 2021 were enrolled in the case group. Propensity score matching (PSM) for sex and age was used to select the control group, which included people who had unilateral sudden sensorineural hearing loss (USSNHL) during the same time period. Hearing recovery, audiological examinations, vestibular function assessments, laboratory tests, and demographic and clinical manifestations were analyzed for intergroup comparisons. Binary logistic regressions were used for both univariate and multivariate analyses of Si-BSSNHL prognostic factors.

Results

Before PSM, the Si-BSSNHL and USSNHL groups differed significantly (p < 0.05) in terms of time from onset to treatment, initial pure-tone average (PTA), final PTA, hearing gain, audiogram curve type, proportion of tinnitus, high-density lipoprotein level, homocysteine level, and effective rate. After PSM, significant differences were also observed in time from onset to treatment, initial PTA, final PTA, hearing gain, total and indirect bilirubin levels, homocysteine level, and effective rate between the two groups (p < 0.05). There was a significant difference in the classification of therapeutic effects between the two groups (p < 0.001). For prognostic analysis, the audiogram curve type was significantly different between the effective group and the ineffective groups of Si-BSSNHL (p = 0.01), in which the sloping type was an independent risk factor for the prognosis of the right ear in Si-SSNHL (95% confidence interval, 0.006-0.549, p = 0.013).

Conclusion

Patients with Si-BSSNHL had mild deafness, elevated total and indirect bilirubin and homocysteine levels, and poorer prognosis than those with USSNHL. Audiogram curve type was linked to the therapeutic effect of Si-BSSNHL, and the sloping type was an independent risk factor for a poor prognosis in the right ear of Si-SSNHL.

Air Pollution Exposure and the Relative Risk of Sudden Sensorineural Hearing Loss in Taipei

(1) Background: The etiologies of sudden sensorineural hearing loss (SSHL) remain unclear. The level of mean particulate matter with a diameter of 2.5 μm or less (PM2.5) was not associated with SSHL, but the maximum PM2.5 level exhibited a negative association with SSHL in Korea. Exposure to nitrogen dioxide (NO2) for 2 weeks increased the risk of SSHL. The lag effects of SSHL after air pollution exposure were limited. We aimed to evaluate the association of SSHL with air pollution exposure to determine whether air pollution exposure caused delayed effects. (2) Methods: This observational study used inpatient data obtained from electronic health records at the Tri-Service General Hospital from 2011 to 2019. The data of all SSHL patients were retrieved. The air quality dataset from Songshan station from 2011 to 2019 was used. The main outcomes were the relative risks (RRs) of SSHL associated with PM2.5, O3, and NO2 exposures within 1 month. The relationships between these factors were examined using distributed lag nonlinear time series models. (3) Results: The RR of SSHL associated with PM2.5 exposure was 1.195 (95% confidence interval (C.I.: 1.047-1.363) for a 10 unit increase at a lag of 7 days. The RR of SSHL associated with O3 exposure was 1.14 (95% C.I.: 1.003-1.3) for a 10 unit increase at a lag of 9 days. The RR of SSHL associated with NO2 exposure was 1.284 (95% C.I.: 1.05-1.57) for a 10 unit increase at a lag of 23 days. (4) Conclusions: In our study, SSHL was confirmed to be associated with air pollution exposure with a lag effect. We discussed possible mechanisms to explore possible biological hypotheses and support further research. Large-scale studies including participants with other ethnicities and causal relationships are needed to confirm our findings.

Hearing Dysfunction After Treatment With Teprotumumab for Thyroid Eye Disease

PURPOSE

To characterize the frequency, severity, and resolution of hearing dysfunction in patients treated with teprotumumab for thyroid eye disease (TED).

DESIGN

Prospective observational case series.

METHODS

Ophthalmic examination and adverse event assessment, including otologic symptoms, were performed at baseline, after infusions 2, 4, and 8, and at 6-month follow-up in consecutive patients who received at least 4 teprotumumab infusions. Laboratory test results were collected at baseline and during treatment. Audiometry, patulous eustachian tube (PET) testing, and otolaryngology evaluation were obtained for patients with new or worsening otologic symptoms, with a subset obtaining baseline and posttreatment testing.

RESULTS

Twenty-seven patients were analyzed (24 females, 3 males, average 56.3 years old). Twenty-two patients (81.5%) developed new subjective otologic symptoms, after a mean of 3.8 infusions (SD 1.8). At 39.2-week average follow-up after the last infusion, most patients with tinnitus (100%), ear plugging/fullness (90.9%), and autophony (83.3%) experienced symptom resolution, whereas only 45.5% (5 of 11) of patients with subjective hearing loss/decreased word comprehension experienced resolution. Six patients underwent baseline and posttreatment audiometry, 5 of whom developed teprotumumab-related sensorineural hearing loss (SNHL) and 1 patient also developed PET. Three of the 5 patients with teprotumumab-related SNHL had persistent subjective hearing loss at last follow-up. A prior history of hearing loss was discovered as a risk factor for teprotumumab-related SNHL (P = .008).

CONCLUSIONS

Hearing loss is a concerning adverse event of teprotumumab, and its mechanism and reversibility should be further studied. Until risk factors for hearing loss are better understood, we recommend baseline audiometry with PET testing and repeat testing if new otologic symptoms develop. Screening, monitoring, and prevention guidelines are needed.

From hormone replacement therapy to regenerative scaffolds: A review of current and novel primary hypothyroidism therapeutics

Primary hypothyroidism severely impacts the quality of life of patients through a decrease in the production of the thyroid hormones T3 and T4, leading to symptoms affecting cardiovascular, neurological, cognitive, and metabolic function. The incidence rate of primary hypothyroidism is expected to increase in the near future, partially due to increasing survival of patients that have undergone radiotherapy for head and neck cancer, which induces this disease in over half of those treated. The current standard of care encompasses thyroid hormone replacement therapy, traditionally in the form of synthetic T4. However, there is mounting evidence that this is unable to restore thyroid hormone signaling in all tissues due to often persistent symptoms. Additional complications are also present in the form of dosage difficulties, extensive drug interactions and poor patience compliance. The alternative therapeutic approach employed in the past is combination therapy, which consists of administration of both T3 and T4, either synthetic or in the form of desiccated thyroid extract. Here, issues are present regarding the lack of regulation concerning formulation and lack of data regarding safety and efficacy of these treatment methods. Tissue engineering and regenerative medicine have been applied in conjunction with each other to restore function of various tissues. Recently, these techniques have been adapted for thyroid tissue, primarily through the fabrication of regenerative scaffolds. Those currently under investigation are composed of either biopolymers or native decellularized extracellular matrix (dECM) in conjunction with either primary thyrocytes or stem cells which have undergone directed thyroid differentiation. Multiple of these scaffolds have successfully restored an athyroid phenotype in vivo. However, further work is needed until clinical translation can be achieved. This is proposed in the form of exploration and combination of materials used to fabricate these scaffolds, the addition of peptides which can aid restoration of tissue homeostasis and additional in vivo experimentation providing data on safety and efficacy of these implants.

Teprotumumab and Hearing Loss: Case Series and Proposal for Audiologic Monitoring

PURPOSE

To present a protocol for audiologic monitoring in the setting of teprotumumab treatment of thyroid eye disease, motivated by 4 cases of significant hearing loss, and review the relevant literature.

METHODS

Cases of hearing loss in the setting of teprotumumab were retrospectively elicited as part of a multi-institutional focus group, including oculoplastic surgeons, a neurotologist and an endocrinologist. A literature review was performed.

RESULTS

An aggregate of 4 cases of teprotumumab-associated hearing loss documented by formal audiologic testing were identified among 3 clinicians who had treated 28 patients.

CONCLUSIONS

Teprotumumab may cause a spectrum of potentially irreversible hearing loss ranging from mild to severe, likely resulting from the inhibition of the insulin-like growth factor-1 and the insulin-like growth factor-1 receptor pathway. Due to the novelty of teprotumumab and the lack of a comprehensive understanding of its effect on hearing, the authors endorse prospective investigations of hearing loss in the setting of teprotumumab treatment. Until the results of such studies are available, the authors think it prudent to adopt a surveillance protocol to include an audiogram and tympanometry before, during and after infusion, and when prompted by new symptoms of hearing dysfunction.

Role of the Stria Vascularis in the Pathogenesis of Sensorineural Hearing Loss: A Narrative Review

Sensorineural hearing loss is a common sensory impairment in humans caused by abnormalities in the inner ear. The stria vascularis is regarded as a major cochlear structure that can independently degenerate and influence the degree of hearing loss. This review summarizes the current literature on the role of the stria vascularis in the pathogenesis of sensorineural hearing loss resulting from different etiologies, focusing on both molecular events and signaling pathways, and further attempts to explore the underlying mechanisms at the cellular and molecular biological levels. In addition, the deficiencies and limitations of this field are discussed. With the rapid progress in scientific technology, new opportunities are arising to fully understand the role of the stria vascularis in the pathogenesis of sensorineural hearing loss, which, in the future, will hopefully lead to the prevention, early diagnosis, and improved treatment of sensorineural hearing loss.

Thyroid-Related Hormone Levels in Clinical Patients With Moderately Severe-to-Profound Sudden Sensorineural Hearing Loss: A Prospective Study

Objectives: Sudden sensorineural hearing loss (SSNHL) is a common otological emergency, causing a measure of hearing loss and affecting the quality of life. This study aims to investigate the association of thyroid-related hormone levels with moderately severe-to-profound SSNHL.

Methods: The study included 70 patients with moderately severe-to-profound SSNHL and 100 age- and sex-matched healthy controls. Peripheral venous blood samples were taken from the participants, and their thyroid-related hormone levels were measured at admission and 1 week after treatment.

Results: In moderately severe-to-profound SSNaHL patients, the concentrations of total triiodothyronine (TT3), total thyroxine (TT4), free triiodothyronine (FT3), and thyroid-stimulating hormone (TSH) (all P < 0.05) were significantly lower than in the control group. The TT3, TT4, FT3, and TSH levels were significantly higher in the effective group than in the ineffective group (all P < 0.05). Linear correlation analysis revealed that TSH level (R = 0.707, P < 0.05) elevation after treatment successfully predicted a favorable outcome of hearing recovery. Logistic regression analyses suggested low FT3 and TSH levels to be independent occurrence predictors, while the increase of TSH level may be an independent favorable outcome predictor.

Conclusions: The results suggest that low FT3 and TSH levels are risk factors for moderately severe-to-profound SSNHL. By discovering the positive association between TSH elevation and hearing recovery, along with the potential novel predictors of FT3 and TSH, our study may contribute valuable insights to the research and treatment of moderately severe-to-profound SSNHL.

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.

A Hospital based study on sudden sensorineural Hearing Loss: It's audiological characteristics and prevalence

Objectives:

To analyze the prevalence & characteristics of sudden sensorineural hearing loss.

Methods:

This cross sectional study including n=377 cases of sensorineural hearing impairment, using non-probability convenience sampling, who fulfilled the selection criteria was conducted from 1^st July 2019 to 31^st October 2019. Study was conducted at Audiology section of ENT department, Lahore General Hospital, Pakistan. Sample included both genders, aged 17-70 years. Cases suffering from inflammatory or obstructive conditions of the external or middle ear and those who could not undergo pure tone audiometry were excluded from the study. Following consent for inclusion in study, data was collected using basic demographic and medical history sheet followed by Audiometric evaluation. Statistical Software for Social Sciences Version 20.0 was used for data analysis.

Results:

The prevalence rate of sudden sensorineural hearing loss of 14(3.7%) being significantly more common in males 11(78%) than females 3(22%) (p=0.05) & age group 15-35 years (p=0.001). It is commonly of severe or profound degree with downward sloping audiogram (p<0.05), however it is not associated with vertigo (p=0.32), tinnitus (p=0.08) with no side predilection (p=0.27).

Conclusion:

We conclude that the prevalence of SSNHL is 3.7% being significantly more prevalent in males and those aged15-25 years. It is mostly characterized by severe to profound degree of hearing loss with downward sloping audiogram with no associated vertigo, tinnitus and side predilection.

Association between SSNHL and Thyroid Diseases

The association between thyroid disease and sudden sensorineural hearing loss (SSNHL) has not been evaluated. We investigated the association of goiter, hypothyroidism, thyroiditis, and hyperthyroidism with sudden sensorineural hearing loss (SSNHL). Data from the Korean National Health Insurance Service-Health Screening Cohort were used. The 8658 SSNHL patients were matched in a 1:4 ratio with 34,632 controls for age, sex, and region of residence. Histories of goiter, hypothyroidism, thyroiditis, hyperthyroidism, and Levothyroxine medication were explored as possible factors influencing SSNHL development. Associations were estimated using conditional logistic regression analyses, adjusted for Levothyroxine medication use. Subgroup analyses were conducted according to age, sex, income, and region of residence. SSNHL patients had a higher rate of goiter occurrence (4.4% vs. 3.7 %, p = 0.001) and hypothyroidism (4.0% vs. 3.2 %, p < 0.001) than controls. Goiter and hypothyroidism were positively associated with SSNHL (adjusted OR =1.14 (95% CI =1.01–1.28), p = 0.043 for goiter and 1.17 (95% CI =1.03–1.33), p = 0.016 for hypothyroidism). In subgroup analyses, hypothyroidism or goiter was more prevalent in SSNHL patients than in controls. Lower-income subgroups showed associations of hypothyroidism and goiter with SSNHL. SSNHL patients were more likely to have goiter and hypothyroidism than normal individuals.