Cochlear dysfunction in patients with acute hypothyroidism

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.

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.

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

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

Study of cochlear function in neonates and infants with congenital hypothyroidism

OBJECTIVE

To investigate the signal amplitudes of transient evoked otoacoustic emissions (TEOAE) in neonates and infants diagnosed with congenital hypothyroidism (HC) and verify their association with clinical and laboratory aspects.

METHODS

A cross-sectional study with a convenience sample of 22 individuals with congenital hypothyroidism and a group of 22 individuals without the disease, neonates and infants, aged 0-12 months. The TEOAE amplitudes were evaluated in both groups and compared using the Mann-Whitney test. The existence of association between TEOAE amplitudes and clinical-laboratory variables was verified through the Spearman correlation coefficient.

RESULTS

There were no statistically significant differences between TEOAE amplitudes between the two groups. There was an association between the amplitudes of TEOAE and serum levels of thyroid stimulating hormone (TSH) and free thyroxine (T4) in the diagnostic test.

CONCLUSIONS

The existence of an association between serum levels of TSH and free T4 in the diagnostic test and the amplitudes of TEOAE suggests the influence of these hormones on the auditory function.

Cochlear dysfunction evidenced by reduction of amplitude of otoacoustic responses in patients with congenital hypothyroidism

INTRODUCTION

The investigation of amplitudes of otoacoustic emissions in congenital hypothyroidism can provide information on cochlear function with more sensibility, when compared to other methods of auditory evaluation.

AIM

To investigate cochlear function through the amplitude of distortion product otoacoustic emissions in individuals with congenital hypothyroidism and to correlate with clinical aspects.

METHODS

An exploratory, analytical, cross-sectional study with a convenience sample, composed of 50 individuals with congenital hypothyroidism and a group of 42 individuals without the disease, mean age of 8.4 (±3.1) years. The subjects of the research were evaluated by means of tonal and speech audiometry, immittance and distortion product otoacoustic emissions (DPOAEs). Continuous variables were described as mean or median and standard deviation. The Spearman test evaluated the correlations between the variables.

RESULTS

Otoacoustic emission amplitudes were significantly reduced in the exposed group, with congenital hypothyroidism, when compared to the group of individuals without the disease, especially in the medium frequencies. The Spearman test showed a slight correlation between the amplitude values of the otoacoustic emissions of some frequencies and the variables: disease time, diagnostic age, irregular serum free thyroxine hormone levels and thyroid stimulating hormone, especially in the condition of less treatment, whose correlation was negative.

CONCLUSION

There was a correlation between the levels of signal amplitudes of otoacoustic emissions with clinical conditions and hormonal follow-up, suggesting probable subclinical auditory impairment in this population, as well as influence of some clinical aspects of congenital hypothyroidism on auditory function.

Self-reported participation restrictions in normal hearing individuals in thyroid ontogeny: Evidence of subclinical changes

Purpose

To verify evidence of subclinical alterations through self-reported participation restrictions in normal hearing individuals and congenital hypothyroidism patients.

Methods

An analytical, quantitative, cross-sectional exploratory study with a 1:1 ratio, consisting of a convenience sample of 86 normal hearing individuals with (n = 42) and without (n = 44) congenital hypothyroidism diagnosis. All participants underwent tonal and speech audiometry, immitance and distortion product otoacoustic emissions. The researchers excluded people with hearing loss, genetic syndromes and metabolic diseases. The instrument used for evaluate of self-reported participation restrictions was the HHIE-adapted questionnaire, composed of 25 questions, 12 of which were social domain and 13 emotional domain. Student's t-test and chi-square test were used for statistical analysis at a significance level of 5%.

Results

There was a significant (p < 0.001) self-reported participation restrictions in CH (61.9%), with a greater relevance for the social domain (p = 0.002). There was a greater frequency of mild/moderate (40.5%) and higher prevalence of association with clinical factors and adherence to treatment.

Conclusion

The findings indicate that self-reported participation restrictions in normal hearing individuals with congenital hypothyroidism was more significant than in the non-exposed group, suggesting evidence of subclinical auditory abnormalities in this population.

Does the use of recombinant TSH in preparation for I-131 scintigraphy scan affect hearing function?

Objective

The objective of this study was to examine the effect of hypothyroidism on hearing function in patients surgically treated for differentiated thyroid cancer and subsequently experienced hypothyroidism during preparation for follow up I-131 scintigraphy scan by either recombinant human thyroid stimulating hormone (rhTSH) treatment or thyroid hormone withdrawal (THW).

Methods

A total of 55 patients undergoing I-131 scintigraphy scan following surgeries for differentiated thyroid cancer were included in the study, including 25 patients prepared by administration of recombinant TSH (rhTSH Group) and 30 patients by thyroid hormone withdrawal (THW Group).

Results

Air conduction thresholds at 1, 2 and 4 kHz for both ears were higher during hypothyroid period than during euthyroid period for patients in the THW group (p < 0.05) but not for patients in the rhTSH group.

Conclusion

Sensorineural hearing loss was detected, especially at low frequencies, in patients with DTC after surgical treatment whose hormone replacement therapy was withdrawn but not in those receiving rhTSH. It is therefore preferred to use rhTSH when preparing for I-131 scintigraphy scan in patients at risk for hearing loss.

Do antithyroid antibodies affect hearing outcomes in patients with pediatric euthyroid Hashimoto's thyroiditis?

OBJECTIVES

Hashimoto's thyroiditis (HT) is the most common autoimmune thyroid disease in children. HT is a multifaceted disease with a variable clinicopathological presentation, including hearing impairment. It is known that hearing function is negatively affected in patients with thyroid disorders. The literature includes a very limited number of studies on hearing function in euthyroid pediatric patients with HT. The aim of this study was to determine the relationship between cochlear function and HT, independent of thyroid function.

MATERIALS AND METHODS

The study included 48 children and adolescents (42 females and 6 males) aged 9-18 years that were diagnosed as HT, and 30 gender- and age-matched healthy controls. Hearing was assessed via otoscopy, tympanometry, pure-tone audiometry, and measurement of distortion product otoacoustic emissions.

RESULTS

There weren't any significant differences in pure tone thresholds between the 2 groups based on pure-tone audiometry, except in the right ear at 6kHz and 8kHz. Distortion product otoacoustic emissions signal to noise ratios were significantly lower in the HT group than in the control group at 4 different frequencies (6kHz [left ear], 8kHz [left ear], 1.5kHz [right ear], and 6kHz [right ear]) (P<0.05). The signal to noise ratios at all frequencies were <6dB in 3% of left ears and 2.5% of right ears in the control group, versus 12.5% of left ears and 9.6% of right ears in the HT group. Distortion product amplitudes were significantly lower in the HT group than in the control group for both left and right ears at 1kHz, 1.5kHz, 3kHz, and 8kHz, and at 2kHz for left ears only (P<0.05).

CONCLUSIONS

The present findings show that cochlear function was lower in the HT group than in the control group. Accordingly, we think that hearing in patients with HT should be monitored periodically, even if their hearing thresholds are within normal limits. Thyroid autoimmunity appears to play an important role in a decrease in cochlear activity in pediatric HT patients.