Metabolic disorders prevalence in sudden deafness

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.

Does glutaric aciduria type 1 affect hearing function?

This study aimed to evaluate audiological findings among patients with glutaric aciduria type 1 (GA-1). We used a large test battery for the audiological evaluation of 17 individuals with GA-1 (the study group) and 20 healthy individuals (the control group). Conventional audiometry (0.125-8 kHz), distortion product otoacoustic emissions (DPOAEs) (1, 1.5, 2, 3, 4, 6, and 8 kHz), contralateral suppression of otoacoustic emissions, and auditory brainstem response (ABR) ( 30, 50, 70 and 90 dB nHL) were measured for all participants (n = 37). Mild sensorineural hearing loss was found in 77.47% (n = 13) of the patients with GA-1, and normal hearing thresholds were seen in 23.53% (n = 4). There were three asymptomatic patients at the time of diagnosis [two developed mild mental motor retardation (MMR) and one developed severe MMR during the follow-up], one with a normal hearing threshold and two with mild hearing loss), and 14 symptomatic patients (three with normal hearing thresholds and 11 with mild hearing loss). Seven of the symptomatic patients diagnosed following an encephalopathic crisis required intensive care and showed significantly worse hearing thresholds than those without symptoms [20.86 ± 4.47 vs. 15.44 ± 3.96 decibel hearing level (dB HL), p = 0.039*], while five had mild-to-moderate hearing loss. Acute encephalopathic crisis had a negative effect on hearing function in the symptomatic patients. The emission and contralateral suppression amplitude values of the study group were significantly lower compared to the control group (p < 0.05). The I-V interpeak latency and absolute latencies of ABR waves I, III, and V of the study group were observed to be significantly prolonged and morphologically distorted compared to those of the control group (p < 0.05). Five patients had MMR, and three had moderate MMR; all eight had mild-to-moderate hearing loss. In addition, of the eight patients with mild MMR, four had mild hearing loss. In particular, the morphological findings of ABR waves were significantly worse in the patients with severe and moderate MMR (p < 0.05). There was a significant correlation between a macrocephaly history (12 patients) and hearing loss (p = 0.041*). Magnetic resonance imaging findings were evaluated in all the 17 patients with GA-1, and typical fronto-temporal atrophy and sylvian fissure enlargement were observed. Our findings support that GA-1 is associated with auditory impairment, primarily in symptomatic patients. Adequate audiological test battery evaluation is essential in this context, particularly for symptomatic patients with a history of encephalopathic crises.

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.

Sudden sensorineural hearing loss - A contemporary review of management issues

Sudden sensorineural hearing loss (SSNHL) is an enigmatic entity, with obscure pathophysiology and debatable efficacy of the treatment agents used. An underlying cause is identified in only 10-15% of cases. The management of the remaining patients, classified as 'idiopathic', is empirical, and is conventionally with systemic steroids, vasodilator therapy, rheological agents, and antioxidants, to list a few amongst the host of the agents employed for the treatment. The availability of conflicting outcomes and lack of conclusive evidence has resulted in the propagation of consensus-based treatment protocols. In the present review, we discuss the various controversial issues and newer developments in the management of idiopathic SSNHL. The current review aims to present a narrative outlook of the updated evidence base available from PUBMED, augmented with relevant designated publications.

Analysis of thyroid dysfunction in patients with sudden sensorineural hearing loss

Background

Sudden sensorineural hearing loss (SSHL) refers to the sudden occurrence of unexplained sensorineural hearing loss. The present study showed that different systemic diseases had different influence on the occurrence and hearing outcome of SSHL. Thyroid hormone is one of the important factors for the development of fetal ear and auditory function. However, the distribution of thyroid dysfunction in SSHL patients and the effect of thyroid dysfunction on the occurrence and hearing outcome of SSHL has not been studied.

Methods

In this study, a retrospective analysis had been done in 676 patients with SSHL. We had described the distribution of thyroid function in patients with SSHL in detail, and by the statistical method, analyzed the relationship between the hearing outcome and thyroid dysfunction, respectively.

Results

In all patients, 24.41% (165/676) had abnormal thyroid function testing results. The onset age of SSHL in FT3 abnormal group (including low and high group) was younger than that in normal FT3 group. Recovery group had more patients with lower-than-normal T3 level as compared to non-recovery patients. Significant associations between T3 levels and hearing outcome were observed in the subgroup with longer time elapse between symptom onset and treatment (≥14 d).

Conclusion

The incidence of thyroid dysfunction in SSHL is significantly higher than in the general population. There was obvious relationship between T3 and FT3 item of thyroid dysfunction and the onset time and hearing outcome of SSHL, which indicated that T3 or FT3 indicator may be one of the affecting factors for the SSHL. Early screening and diagnosis of thyroid dysfunction, especial T3 level, may help to evaluate the prognosis in SSHL patients.

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

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

Microvascular dysfunction affects the development and prognosis of sudden idiopathic hearing loss

OBJECTIVE

The aim of our study is to investigate whether systemic microvascular function affects the development and prognosis of sudden idiopathic hearing loss (SHL).

TYPE OF STUDY

A prospective case-control study.

MATERIALS AND METHODS

Fifty patients diagnosed with SHL at our hospital between September 2015 and May 2016 were included as the SHL group, and 50 healthy volunteers who came to the hospital for medical screening were included in the control group. Thirty-one patients from the SHL group who responded to treatment and 19 patients who did not respond to treatment were identified according to the Siegel criteria and were grouped. Patients with comorbid disorders were excluded from the study. To determine microvascular function, the videocapillaroscopic examination was conducted from the nailfold, measuring the capillary density (CD) and post-occlusive reactive hyperaemia (PORH) values and statistical analysis was performed between the groups.

RESULT

While CD was an average of 83.1 ± 6 in the SHL group, it was measured as 96.2 ± 10 in the control group. The CD value was significantly lower in the SHL group than the control group (P < 0.05). While the average PORH value in the SHL group was 80.5 ± 7.7, it was measured as 97.5 ± 10 in the control group. The PORH value was significantly lower in the SHL group than the control group (P < 0.05). The CD value did not differ significantly (P > 0.05) between the group that responded to treatment (83.4 ± 5.5) and the group that did not respond to treatment (82.7 ± 6.9). The PORH value was significantly lower (P < 0.05) in the group that did not respond to treatment (75.2 ± 7.9) than the group that did (83.8 ± 5.6).

CONCLUSION

To our best knowledge, our study is the first study in the literature. Although the role of specific mechanisms in SHL is not entirely understood, the capillaroscopic examination can show the importance of microvascular function in SHL. CD and PORH values were found to be low in SHL patients, and a low PORH value was found to be a factor of poor prognosis.

Glucose metabolism disorders and vestibular manifestations: evaluation through computerized dynamic posturography

INTRODUCTION

Global sugar consumption has increased in the past 50 years; its abusive intake is responsible for peripheral insulin resistance, which causes the metabolic syndrome - obesity, diabetes mellitus, hypertension, and coronary heart disease.

OBJECTIVE

To evaluate the effect of a fractionated diet without glucose as treatment for labyrinthine disorders associated with glucose-insulin index.

METHODS

The study design was a prospective randomized controlled trial. Fifty-one patients were divided into two groups: the diet group (DG), which comprised subjects treated with a fractionated diet with glucose restriction, and the control group (CG), in which individuals were not counseled regarding diet. Patients underwent computerized dynamic posturography (CDP) and visual analog scale (VAS) on the first and 30th days of the study.

RESULTS

There was improvement in the assessed posturographic conditions and VAS self-assessment in the DG group after 30 days when compared to the control group.

CONCLUSION

The fractionated diet with glucose restriction was effective for the treatment of vestibular dysfunction associated with glucose metabolism disorders.

Gallstone is correlated with an increased risk of idiopathic sudden sensorineural hearing loss: a retrospective cohort study

OBJECTIVES

This study aims to test the hypothesis that gallstone disease (GSD) is a risk factor for the development of idiopathic sudden sensorineural hearing loss (ISSNHL). Research has shown risks of cardiovascular and cerebrovascular events in patients with GSD; however, well-conducted English studies on the association between GSD and the development of ISSNHL are lacking.

DESIGN AND SETTING

Retrospective cohort study using the Taiwan Longitudinal Health Insurance Database.

PARTICIPANTS

We compared 26,449 patients diagnosed with GSD between 1 January 2001 and 31 December 2007, with 52,898 age-matched, gender-matched and comorbidities propensity scores-matched controls.

OUTCOME MEASURED

We followed each patient until the end of 2011 and evaluated the incidence of ISSNHL for at least 4 years after the initial GSD diagnosis.

RESULTS

The incidence of ISSNHL was 1.42 times higher in the GS cohort than in the non-GS cohort (9.27 vs 6.52/10,000 person-years). Using Cox proportional hazard regressions, the adjusted HR was 1.44 (95% CI 1.19 to 1.74). In the cohort of patients with GSD who needed a cholecystectomy, 37 patients suffered from ISSNHL. Among those patients, 31 (83.7%) patients sustained ISSNHL before cholecystectomy and 6 (16.2%) patients sustained ISSNHL after cholecystectomy.

CONCLUSIONS

A diagnosis of GSD may be an independent risk for ISSNHL. This finding suggests that an underlying vascular and inflammatory mechanism may contribute to the development of ISSNHL. Physicians may want to counsel patients with GSD to seek medical attention if they have hearing impairments, because patients may be at an increased risk of developing ISSNHL.

Inner ear symptoms: can we use them to approach cardiovascular diseases?

Sensory organs are programmed to detect external stimuli, and inform about possible threats. In general, they are characterized by a complex architecture, a highly energy-requiring function, a peripheral location and a vascular supply depending on a terminal circulation usually under systemic control. Their function may be highly sensitive to more general disorders primarily involving other organs or physiological systems. Consequently, the onset of transient or persistent symptoms of impairment of sensory organs might be the expression of abnormalities in the integrity of more general systems, especially in the elderly population. In the otologic area, despite the availability of evidence supporting the negative impact of some systemic conditions negatively affecting the local blood supply at the labyrinth level, the possibility that the inner ear can reveal the presence of sub-clinical, non-otologic disorders has never been the topic of a constructive investigation. The present review summarizes the preliminary available evidence suggesting a possible negative impact of early systemic hemodynamic changes on the function of the inner ear, as well as the possibility that some audiological symptoms may play some role in the early detection of cardiovascular diseases. In particular, we hypothesize that some cardiovascular diseases may cause an impairment in correct labyrinthine function as a result of a negative interaction between systemic hemodynamic changes, a reflex activation of the autonomic nervous system, and a local vascular response. A multidisciplinary approach to the interpretation of inner ear disorders may increase the possibility of an earlier recognition and understanding of systemic dysfunctions in clinical practice.

Lipid Profile among Patients with Sudden Sensorineural Hearing Loss

Associations between hearing and blood lipids have been the focus of scientific inquiry for more than 50 years. The aim of the present study is to evaluate the association between hyperlipidaemia among patients presented with sudden sensorineural hearing loss compared to normal controls. A case control study concerned with 22 patients presented with sudden sensorineural hearing loss who underwent lipid profile evaluation. The lipid profile of these patients was compared with corresponding results of 55 age matched persons (volunteers) with normal hearing. These patients were collected from the Out Patient Department of ENT at Al-Jamhory Teaching Hospital, Mosul/Iraq and private clinic of the author for the period from February 2011 to July 2013. The average age of patients was 44.7 years with a range of 26-65 years. The peak age incidence was in the 5(th) decade of life. The study included 11 male patients (50 %) and 11 females (50 %). Meanwhile, the average age of the control group was 41.7 years with 25 (45.5 %) males and 30 (54.5 %) females. Statistical analysis showed that there was significant difference between the means of lipid profile and blood sugar of the patients and the control group apart from HDL where there was no significant difference. In conclusion, hyperlipidemia seems to be significantly associated with the occurrence of sudden sensorineural hearing loss according to this study.

Contribution of audiovestibular tests to the topographic diagnosis of sudden deafness

Introduction: Sudden hearing loss (SHL) is an ENT emergency defined as sensorineural hearing loss (SNHL) ≥ 30 dB HL affecting at least 3 consecutive tonal frequencies, showing a sudden onset, and occurring within 3 days. In cases of SHL, a detailed investigation should be performed in order to determine the etiology and provide the best treatment. Otoacoustic emission (OAE) analysis, electronystagmography (ENG), bithermal caloric test (BCT), and vestibular evoked myogenic potential (VEMP) assessments may be used in addition to a number of auxiliary methods to determine the topographic diagnosis.

Objective To evaluate the contribution of OAE analysis, BCT, VEMP assessment, and magnetic resonance imaging (MRI) to the topographic diagnosis of SHL.

Method Cross-sectional and retrospective studies of 21 patients with SHL, as defined above, were performed. The patients underwent the following exams: audiometry, tympanometry, OAE analysis, BCT, VEMP assessment, and MRI. Sex, affected side, degree of hearing loss, and cochleovestibular test results were described and correlated with MRI findings. Student's t-test was used for analysis of qualitative variables (p < 0.05).

Results The mean age of the 21 patients assessed was 52.5 ± 15.3 years; 13 (61.9%) were women and 8 (38.1%) were men. Most (55%) had severe hearing loss. MRI changes were found in 20% of the cases. When the audiovestibular test results were added to the MRI findings, the topographic SHL diagnosis rate increased from 20% to 45%.

Conclusion Only combined analysis via several examinations provides a precise topographic diagnosis. Isolated data do not provide sufficient evidence to establish the extent of involvement and, hence, a possible etiology.

Risk of developing sudden sensorineural hearing loss in diabetic patients: a population-based cohort study

OBJECTIVES

To explore the risk of development of sudden sensorineural hearing loss (SSHL) among diabetes mellitus patients.

STUDY DESIGN

A retrospective cohort study.

SETTING

Population-based study of Taiwan National Health Insurance Research Database.

PATIENTS

Approximately 26,556 newly diagnosed diabetic patients and 26,556 comparison subjects without diabetes mellitus were selected from claims made during 2000 to 2004.

MAIN OUTCOME MEASURES

The incidence of sudden sensorineural hearing loss (SSHL) at the end of 2009 was determined.

RESULTS

The incidence of SSHL was 1.54-fold higher in the diabetic group compared with the nondiabetic group (1.29 versus 0.78 per 1,000 person-years), and using Cox proportional hazard regressions, the adjusted hazard ratio (HR) was 1.592 (95% confidence interval [CI], 1.295-1.957). The risk of developing SSHL increased substantially to an HR of 2.060 (95% CI, 1.051-4.037), for patients who required triple antidiabetic medication compared with diabetic patients treated with a single antidiabetic drug. An increased risk of developing SSHL, with adjusted HRs of 1.574 (95% CI, 1.091-2.271) and 2.842 (95% CI, 1.880-4.295), was observed in diabetic patients with newly diagnosed comorbidities of retinopathy or retinopathy combined with renal insufficiency, which are both expected to reflect the severity of diabetes.

CONCLUSION

Diabetes mellitus was significantly associated with an increased risk of developing SSHL. Coronary heart disease or retinopathy comorbidities in diabetic patients seemed to be associated with an increased risk of developing SSHL. The risk of developing SSHL increased with the severity of diabetes.

Development and analysis of a low-cost screening tool to identify and classify hearing loss in children: a proposal for developing countries

OBJECTIVE

A lack of attention has been given to hearing health in primary care in developing countries. A strategy involving low-cost screening tools may fill the current gap in hearing health care provided to children. Therefore, it is necessary to establish and adopt lower-cost procedures that are accessible to underserved areas that lack other physical or human resources that would enable the identification of groups at risk for hearing loss. The aim of this study was to develop and analyze the efficacy of a low-cost screening tool to identify and classify hearing loss in children.

METHODS

A total of 214 2-to-10 year-old children participated in this study. The study was conducted by providing a questionnaire to the parents and comparing the answers with the results of a complete audiological assessment. Receiver operating characteristic (ROC) curves were constructed, and discriminant analysis techniques were used to classify each child based on the total score.

RESULTS

We found conductive hearing loss in 39.3% of children, sensorineural hearing loss in 7.4% and normal hearing in 53.3%. The discriminant analysis technique provided the following classification rule for the total score on the questionnaire: 0 to 4 points - normal hearing; 5 to 7 points - conductive hearing loss; over 7 points - sensorineural hearing loss.

CONCLUSION

Our results suggest that the questionnaire could be used as a screening tool to classify children with normal hearing or hearing loss and according to the type of hearing loss based on the total questionnaire score.