Association between the atherogenic index of plasma and hearing loss based on a nationwide cross-sectional study

BACKGROUND

Hearing loss (HL) is a worldwide public health issue for which the role of dyslipidemia has not been fully elucidated. This study aimed to use the atherogenic index of plasma (AIP), a well-established serum lipid marker, to investigate the association of dyslipidemia with HL among the general population.

METHODS

Participants (n = 3267) from the National Health and Nutrition Examination Survey database (2005-2012, 2015-2018) were included in the present study. The AIP was calculated based on the following formula: log10 (triglycerides/high-density lipoprotein cholesterol). HL was defined as a pure-tone average of at least 20 dBHL in the better ear. Weighted multivariable logistic regression, subgroup analysis, generalized additive model, and threshold analysis were adopted to reveal the association between the AIP and HL.

RESULTS

In this study of US adults, a positive association was found between the AIP and high-frequency HL. However, the association between the AIP and low-frequency HL was not as strong. In addition, a reverse L-shaped curve with an inflection point located at -0.27 was detected between the AIP and high-frequency HL, followed by a significant positive association after the inflection point.

CONCLUSIONS

The potential of the AIP as a bioindicator for high-frequency HL is noteworthy, and maintaining an AIP value below a certain threshold might provide beneficial outcomes in the management of high-frequency HL.

Traditional and non-traditional lipid parameters as risk factors for sudden sensorineural hearing loss

OBJECTIVE

The purpose was to explore the effects of traditional and non-traditional lipid parameters on Sudden Sensorineural Hearing Loss (SSNHL).

METHODS

The study included 452 patients diagnosed with SSNHL, among whom 206 patients had a level of hearing improvement ≥10 dB after one month of follow-up. A propensity score-matched (2:1) control group was used. Conditional and unconditional logistic regression were used to analyze the risk factors for SSNHL.

RESULTS

Patients with SSNHL had a higher risk of concomitant hypertension and elevated atherosclerogenic lipid levels, with apolipoprotein B and apolipoprotein E identified as independent risk factors for the onset of SSNHL. Additionally, the Lipid Comprehensive Index (LCI) was an independent risk factor for the degree of hearing loss. A positive linear correlation was revealed between triglyceride, non-high-density lipoprotein cholesterol, atherogenic index, Castelli risk index, atherogenic index of plasma, LCI and hearing loss. However, no linear relationship was observed between hearing gain and any lipid parameters. When Total Cholesterol (TC) was in the range of borderline high, the treatment effect was the best. However, the statistical significance disappeared upon adjusting for confounding factors.

CONCLUSION

Patients with SSNHL exhibited markedly dysregulated lipid metabolism. Elevated serum lipid levels may be a causative factor in auditory impairment and can influence the extent of hearing loss. Promptly improving cochlear microcirculation may benefit patients with borderline elevated TC.

LEVEL OF EVIDENCE: 4

Contemporary Review of Idiopathic Sudden Sensorineural Hearing Loss: Management and Prognosis

Sudden sensorineural hearing loss (SSNHL) is a rapid decline in auditory function that needs urgent medical management. Although etiologic factors, including viral infections, autoimmune diseases, and vascular issues, contribute to the understanding of SSNHL, the condition remains unclear in most cases. Systemic steroids are often used as the first-line treatment because they reduce inner ear inflammation; however, there remains numerous discussions about the effectiveness of alternative treatments. To predict hearing recovery is crucial in patients' counseling with factors, including delayed treatment, vertigo, and other health conditions, which indicate poor prognosis. Herein, we review contemporary research on the treatment approaches and outcome predictions of SSNHL to establish important guidelines for physicians in evaluating and treating patients with SSNHL.

Herpes Zoster Oticus with Concurrent Hearing Loss: A Study on Clinical Characteristics and Prognosis

This study aimed to analyze the clinical characteristics and treatment prognoses of patients with Herpes Zoster Oticus (HZO) and concurrent hearing loss (HL). Various clinical characteristics of 192 patients with HZO, with or without concurrent HL, from 2016 to 2020 were retrospectively analyzed through a chart review. All patients were followed-up until recovery or up to 12 months. Demographic and clinical findings were compared between the groups, and the recovery rates of facial palsy, hearing, and other clinical features were analyzed. Facial palsy recovery was analyzed using the House-Brackmann (HB) grading system, and hearing recovery rates were analyzed using the Siegel criteria. Of the 192 patients diagnosed with HZO, 142 had no hearing loss (HZO without HL), and 50 had hearing loss (HZO with HL). While both groups had similar ages, treatment timings, and underlying diseases, the HZO w HL group had a significantly higher rate of dizziness and tinnitus, but received more intratympanic steroid injections. In terms of facial palsy, there were no significant differences in the initial HB grade or recovery rates between the groups. Within the HZO w HL group, hearing loss severity varied, with 52% experiencing mild loss and only 16% achieving complete recovery. Descending-type audiograms were the most common at 66%. In patients with HZO, there was no statistically significant difference between the degree of initial facial paralysis and the degree of recovery of the final facial paralysis according to concurrent HL. However, among patients with concurrent HL, the hearing recovery rate in the HZO group was low.

The relationship between serum lipid and sudden sensorineural hearing loss

BACKGROUND

Hyperlipidemia may be part of the important mechanisms for the development of idiopathic sudden sensorineural hearing loss (ISSNHL).

AIMS

So the purpose of this study was to evaluate the relationship between changes in blood lipid levels and ISSNHL.

MATERIALS AND METHODS

We enrolled 90 ISSNHL patients in our hospital using a retrospective study design from 2019.1 to 2021.12. Blood levels of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL-C). Hearing recovery was analyzed using the chi-square test and one-way analysis of variance (ANONA). Univariate and multifactorial Logstic retrospective analyses to establish the relationship between LDL-C/HDL-C ratio and hearing recovery after adjustment for potential confounding factors.

RESULTS

In our study, 65 (72.2%) patients had their hearing recovered. All group analyses and three group analyses (i.e. Excluding the no-recovery group) found that LDL/HDL was on an upward trend from complete recovery to a slight recovery group and strongly associated with hearing recovery. Univariate and multivariate logistic regression analysis found high levels of LDL and LDL/HDL in the partial hearing recovery group, relative to the full hearing recovery group. Curve fitting intuitively demonstrates the influence of blood lipids on prognosis.

CONCLUSIONS

Our findings suggest that LDL. TC, TC/HDL, and LDL/HDL concentrations may be closely related to the pathogenesis of ISSNHL.

SIGNIFICANCE

Improving the relevant lipid test at the time of admission to the hospital has good clinical significance for improving the prognosis of ISSNHL.

Update on Findings about Sudden Sensorineural Hearing Loss and Insight into Its Pathogenesis

Sudden sensorineural hearing loss (SSNHL) is routinely encountered and is one of the most common emergent diseases in otolaryngology clinics. However, the etiology of SSNHL remains unclear. Due to the inaccessibility of the living human inner ear for biopsy, studies investigating the etiology of SSNHL have been performed by analyzing data obtained from examinations using peripheral blood or imaging. We updated the findings obtained from serological, magnetic resonance imaging, genetic, and viral examinations to reveal the etiology of SSNHL. Regarding viral examination, we focused on sensorineural hearing loss associated with coronavirus disease (COVID-19) because the number of correlated reports has been increasing after the outbreak. The updated findings revealed the following three possible mechanisms underlying the development of SSNHL: thrombosis and resulting vascular obstruction in the cochlea, asymptomatic viral infection and resulting damage to the cochlea, and cochlear inflammation and resulting damage to the cochlea. Thrombosis and viral infection are predominant, and cochlear inflammation can be secondarily induced through viral infection or even thrombosis. The findings about sensorineural hearing loss associated with COVID-19 supported the possibility that asymptomatic viral infection is one of the etiologies of SSNHL, and the virus can infect inner ear tissues and directly damage them.

Identification of dyslipidemia as a risk factor for sudden sensorineural hearing loss: A multicenter case-control study

Background

Recently, several studies have reported an association between lipid profiles and sudden sensorineural hearing loss (SSNHL), yet there is considerable variability between the individual studies in defining the precise association between serum lipids levels and SSNHL. This study sought to identify a possible relationship between dyslipidemia and the prevalence and prognosis of SSNHL.

Methods

A case‐control study was carried out at two independent medical centers, including 2,288 SSNHL patients and 2,288 healthy controls. Clinical characteristics and serum lipid parameters were assessed, including total cholesterol (CHOL), high‐density lipoprotein (HDL), low‐density lipoprotein (LDL), triglycerides (Trig), apolipoprotein AI (ApoAI), apolipoprotein B (ApoB), and lipoprotein a (Lpa). Multivariate logistic regression analysis was performed to assess the relationship between lipid profiles and SSNHL in the 4,576 subjects.

Results

Significant differences were identified in several conventional serum lipid markers including CHOL, Trig, HDL, LDL, ApoAI, ApoB, and Lpa, between SSNHL patients and healthy controls. Serum ApoAI levels were significantly lower in patients with bilateral SSNHL compared to unilateral SSNHL. Binary logistic regression analysis revealed that higher levels of ApoB, LDL, Trig, and lower levels of ApoAI and HDL were all associated with an increased risk of SSNHL. After clinical characterization, multivariate analysis showed that only low levels of ApoB predicted likelihood of a recovery of more than 30 dB among patients with SSNHL.

Conclusions

Serum lipids are associated with the incidence and prognosis of SSNHL. Identification of dyslipidemia may improve early evaluation and management of SSNHL risks.

LDLR expression in the cochlea suggests a role in endolymph homeostasis and cochlear amplification

There is now growing evidence that hypercholesterolemia and high serum levels of low-density lipoproteins (LDL) predispose to sensorineural hearing loss. Circulating LDL-cholesterol is delivered to peripheral tissues via LDL receptor (LDLR) -mediated endocytosis. Recently, it has been shown that LDLR gene polymorphisms are associated with higher susceptibility to sudden deafness. These findings suggested that we should investigate the expression of LDLR from the postnatal maturation of the mouse cochlea until adulthood. In the cochlea of newborn mice, we observed that LDLR is mostly expressed in the lateral wall of the cochlea, especially in a band of cells directly facing the cochlear duct. Moreover, LDLR is expressed in the inner and outer hair cells, as well as in the adjacent greater epithelial ridge. In early postnatal stages, LDLR is expressed in the marginal cells of the immature stria vascularis, in the root cells of the spiral ligament, and in the adjacent outer sulcus cells. At the same time, LDLR begins to be expressed in the pillar cells of the immature organ of Corti. From the onset of hearing, LDLR is expressed in the marginal cells of the stria vascularis, in the outer sulcus cells, and in the capillaries of the adjacent spiral ligament. In the organ of Corti, LDLR is expressed in outer pillar cells and Deiters' cells, i.e. in the non-sensory supporting cells that directly surround the outer hair cells. These cells are believed to provide a mechanical coupling with the outer hair cells to modulate electromotility and cochlear amplification. In the stria vascularis of three-month-old mice, LDLR is further expressed in both marginal and intermediate cells. Overall, our results suggest that LDLR is mostly present in cochlear cells that are involved in endolymph homeostasis and cochlear amplification. Further functional studies will be needed to unravel how LDLR regulates extracellular and intracellular levels of cholesterol and lipoproteins in the cochlea, and how it could influence cochlear homeostasis.

Correlation between serum lipid and prognosis of idiopathic sudden sensorineural hearing loss: a prospective cohort study

BACKGROUND

To investigate the correlation between blood lipids and the prognosis of idiopathic sudden sensorineural hearing loss (ISSNHL).

METHODS

We included 232 patients with ISSNHL at the Second Affiliated Hospital of Shanghai University from June 2015 to March 2017 using a prospective cohort study design. We collected information including age, gender, hypertension, diabetes, mellitus, vertigo, as well as the levels of blood total cholesterol (TC), triglycerides (TG), and low-density lipoproteins (LDL-C). We also recorded the ratio between the levels of low-density lipoproteins and the levels of high-density lipoproteins (LDL-C/HDL-C ratio). Correlations between the prognosis of ISSNHL and TC, TG, LDL-C, and LDL-C/HDL-C ratio were analyzed by univariable and multivariable logistic regression analyses.

RESULTS

The clinical effectiveness rate of patients with TC ranging from 5.2 to 6.2 mmol/L was significantly higher than that of patients with TC <5.2 mmol/L (P<0.001). No notable difference was found between patients with TC <5.2 mmol/L and patients with TC ≥6.2 mmol/L. The clinical effectiveness rate of patients in TG ranging from 1.7 mmol/L to 2.3 mmol/L was markedly higher than those in TG <1.7 mmol/L (P<0.001). No significant difference was found between patients with TG ranging from 2.3 to 5.6 mmol/L, TG ≥5.6 mmol/L, and TG <1.7 mmol/L. The clinical effectiveness rate of patients in LDL-C/HDL-C <1.5 was considerably higher than those in LDL-C/HDL-C ranging from 1.5 to 2.5, 2.5 to 3.5, and ≥3.5 (P<0.001).

CONCLUSIONS

Our findings indicated that TC, TG, and the LDL-C/HDL-C ratio are strongly associated with the prognosis of ISSNHL. These three indices could be recommended as independent markers to predict outcomes.

Sudden sensorineural hearing loss: What factors influence the response to therapy?

The standard treatment of Sudden Sensorineural Hearing Loss is based on oral steroids. In addition, intratympanic steroid is currently used in patients who fail to respond to oral treatment. The aim of the present study was to evaluate, in patients affected by SSHL, factors that influence the response to systemic and intratympanic steroid treatment. A retrospective analysis was conducted on 149 patients, all treated with systemic steroids. Moreover, patients not responsive to systemic therapy were treated with intratympanic steroids as salvage therapy. Auditory gain was assessed through the recovery rate at the discharge and after 30 days. Statistical analysis demonstrated that patients with delayed treatment and down-sloping auditory curve presented a poor recovery. Linear and stepwise regression showed that hypertriglyceridemia and hyperglycemia were negative prognostic factors. The prognosis of SSHL is affected by hyperglycemia and hypertriglyceridemia suggesting that a microvascular dysfunction within the cochlea could impair hearing recovery. Intratympanic steroid treatment was used as salvage treatment, however in patients with poor prognostic factors or at risk for side effects, it could be used in association with systemic treatment.

Clinical Characteristics and Prognosis of Sudden Sensorineural Hearing Loss in Post-irradiated Nasopharyngeal Carcinoma Survivors

OBJECTIVES

Sudden sensorineural hearing loss (SSNHL) may occur in post-irradiated nasopharyngeal carcinoma (NPC) survivors with a rare rate. This study was conducted to evaluate the clinical characteristics and prognosis of this population.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary otology referral center.

PATIENTS

Five hundred ninety nine SSNHL patients were recruited between January 2010 and January 2019. Patients were divided into two groups: NPC group (n = 24) and non-NPC group (n = 575).

INTERVENTIONS

All SSNHL patients were diagnosed by pure tone audiometry and treated with steroids, blood flow promoting agents, and hyperbaric oxygen therapy.

MAIN OUTCOME MEASURES

We evaluated the clinical characteristics and prognosis of post-irradiated SSNHL and identified prognostic factors by logistic regression analysis.

RESULTS

In the NPC group, the initial hearing threshold, contralateral hearing threshold, rate of vertigo, rate of profound hearing loss were all higher than in the non-NPC group (p < 0.05). Hearing gains and the rate of good recovery (both complete recovery and partial recovery) were lower in the NPC group than in the non-NPC group (p < 0.05). Logistic regression analysis revealed that NPC was significantly associated with poor hearing recovery (OR = 3.499, p = 0.040), and that a higher initial hearing threshold and longer treatment delay time were related to a poor prognosis (p < 0.05).

CONCLUSIONS

SSNHL occurred in post-irradiated NPC survivors often suffered a severe hearing loss with a high rate of accompanying vertigo. NPC may have an adverse impact on the prognosis of SSNHL, and higher initial hearing threshold and longer treatment delay time were indicators of poor hearing recovery.

Increased atherogenic index in the general hearing loss population

Purpose

The purpose of this study was to evaluate the association of hearing loss with atherogenic index (AI) in the general population.

Methods

A multistage study using cluster random sampling method was conducted in the Zhejiang province from 2016 to 2018. Pure-tone air-conduction hearing thresholds were measured at frequencies of 0.125-8 kHz for each subject. After obtaining their consent, all participants were asked to provide their own plasma lipid data.

Results

A total of 3,414 eligible participants were included, 1,765 (51.7%) were men and 1,649 (48.3%) were women and 1,113 (32.6%) had hearing loss. Ridge regression showed increased AI in subjects with hearing loss. The subgroup with the highest quartile of AI, presenting the highest risk of hearing loss as compared to the lowest quartile, comprised young and middle-aged women. Further analysis revealed that the AI in people with different categories of hearing loss was higher than that in the normal population, except for those with (extremely) severe hearing loss. Moreover, the young and middle-aged women exhibited the most significant correlations between AI and hearing loss.

Conclusion

AI was positively associated with hearing loss in the general population, especially the young and middle-aged women.

The Influence of Metabolic Syndrome on the Prognosis of Idiopathic Sudden Sensorineural Hearing Loss

OBJECTIVES

We aimed to verify the hypothesis that metabolic syndrome (MetS) and its components affect the prognosis of idiopathic sudden sensorineural hearing loss (ISNNHL).

STUDY DESIGN

A retrospective cohort study.

SETTING

Tertiary otology referral center.

PATIENTS

We divided patients who were diagnosed with ISSNHL between January 2015 and January 2018 into a MetS group and a Non-MetS group according to the diagnostic criteria of MetS.

INTERVENTIONS

We diagnosed ISSNHL patients by using pure-tone audiometry and treated them with oral steroids, blood flow promoting agents, and hyperbaric oxygen therapy.

MAIN OUTCOME MEASURES

We used multivariate logistic analysis to identify prognostic factors of ISSNHL.

RESULTS

The MetS group comprised 94 patients, and the Non-MetS group comprised 162 subjects. Despite the rate of hypertension, diabetes mellitus, hyperlipidemia, and BMI, no significant difference was observed between the two groups (p > 0.05). The rates of complete recovery and partial recovery of the MetS group were significantly lower than those of the Non-MetS group (p < 0.05). According to the multivariate analysis, MetS was significantly correlated with a poor prognosis (OR = 2.912, p = 0.008), and the OR increased with an increase in the number of MetS components. Late onset of treatment, high initial hearing threshold, and presence of diabetes mellitus and hyperlipidemia were associated with a poor prognosis (p < 0.05).

CONCLUSIONS

The presence of MetS may negatively affect the recovery of Chinese patients with ISSNHL, and the prognosis was poorer with an increase in the number of MetS components. Early onset of treatment, low initial hearing threshold and absence of diabetes mellitus, and hyperlipidemia are associated with favorable hearing recovery.

White Matter Abnormalities of Auditory Neural Pathway in Sudden Sensorineural Hearing Loss Using Diffusion Spectrum Imaging: Different Findings From Tinnitus

Sudden sensorineural hearing loss (SSNHL) is a complex and challenging emergency which requires evidence regarding its pathophysiological changes to guide the treatment. The aim of this study was to evaluate the white matter integrity of the auditory neural pathway in patients with unilateral SSNHL in acute stage by using diffusion spectrum imaging tractography. In the present study, 60 individuals with acute SSNHL (29 males, 50.7 ± 11.8 years) and 25 healthy controls (13 males, 45.2 ± 13.2 years) underwent diffusion spectrum imaging tractography and high resolution T1 structural examinations using a 3T magnetic resonance imaging system. The areas of the auditory neural pathway were defined as regions of interest (ROIs). The quantitative anisotropy (QA) and the generalized fractional anisotropy (GFA) were compared between the patients with unilateral SSNHL and controls in these ROIs. We further evaluated the correlation between the parameter values and hearing loss level. The mean pure tone audiometry of patients at the onset presentation was 63.2 ± 26.2 dB. The right-sided SSNHL was involved in 25 (41.7%) cases and the left-sided in 35 (58.3%) cases. The QA values in the contralateral medial geniculate body, the bilateral anterior corona radiata and the anterior limb of internal capsule were significantly reduced in SSNHL patients compared to controls. In addition, the decrease QA value of the contralateral medial geniculate body was related to the increase severity of disease, even after controlling potential confounding factors. The present study demonstrated that patients with SSNHL exhibited altered integrity of white matter in the auditory neural pathway. Furthermore, the decreased QA values in the contralateral medial geniculate body might predict the severity of this disease. In the present study, tinnitus has not been found to effect in brain area obviously.

Metabolic syndrome components and sudden sensorineural hearing loss: a case-control study

PURPOSE

Cardiovascular risk factors, including metabolic syndrome (MetS) components, were reported as possible risk factors of sudden sensorineural hearing loss (SSNHL). The objective of this study was to evaluate the relationship between MetS (and its components) and SSNHL.

METHODS

Eighty-one SSNHL patients and 243 sex-, aged-matched controls participated from January 2018 to July 2019. The participants included 176 (54.3%) men and 148 (45.7%) women. The correlation between Mets components, total cholesterol, low-density lipoprotein-cholesterol, and the onset of SSNHL was analyzed using used multivariate conditional logistic regression analysis.

RESULTS

A total 12 patients (14.8%) with SSNHL and 27 subjects (11.1%) in control group had MetS (p > 0.05). The rate of low levels of high-density lipoprotein-cholesterol (HDL-C), hypertriglyceridemia, and hypertension was significantly higher in the SSNHL group than those in the control group (p < 0.05). A trend of odds SSNHL was observed with increasing the number of MetS components (p < 0.001). The multivariable analysis revealed that the rate of hypertriglyceridemia and low HDL-C concentration was significantly higher in the SSNHL groups compared to the controls.

CONCLUSIONS

Hypertriglyceridemia and low levels of HDL-C may be important factors in the pathogenesis of SSNHL, and should be assessed during the investigation of patients with this condition.

Effect of systemic lupus erythematosus and rheumatoid arthritis on sudden sensorineural hearing loss

OBJECTIVES

Recent reports have identified autoimmune systemic diseases as a significant risk factor for sudden sensorineural hearing loss (SSNHL). We investigated whether systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) were correlated with the hearing recovery of SSNHL.

STUDY DESIGN

A retrospective study.

METHODS

Records of 663 SSNHL patients between January 2008 and January 2019 were retrospectively reviewed, including demographic, comorbid diseases, and hearing recovery. Patients were divided into four groups (complete, partial, slight, and no recovery) according to Siegel's criteria and Chinese Medical Association of Otolaryngology (CMAO) criteria. Multinomial logistic regression was performed to evaluate the effects of onset of treatment, initial hearing threshold, audiogram pattern, diabetes mellitus, SLE, and RA on the prognosis of SSNHL according to both criteria.

RESULTS

Patients in complete recovery, partial recovery, slight recovery, and no improvement were 95 (14.3%), 183 (27.6%), 170 (25.6%), and 215 (32.4%) by Siegel's criteria, and 90 (13.6%), 152 (22.9%), 188 (28.4%), and 233 (35.1%) by CMAO criteria, respectively. Among the four groups, onset of treatment, initial hearing threshold, diabetes mellitus, SLE, RA, and profound audiogram pattern were found to be associated with recovery outcome by both Siegel's criteria and CMAO criteria (P < .05). According to analysis results, presence of SLE, RA, diabetes mellitus and higher initial hearing threshold were significantly correlated with a poor prognosis by both Siegel's criteria and CMAO criteria (P < .05).

CONCLUSION

Comorbid SLE or RA may negatively affect the prognosis of SSNHL. Lower initial hearing threshold and absence of diabetes mellitus are associated with favorable hearing recovery.

LEVEL OF EVIDENCE

4. Laryngoscope, 130:2475-2480, 2020.

Characteristics and prognosis of idiopathic sudden sensorineural hearing loss in aged people: a retrospective study

Background: Few studies focused on the prognosis of sudden sensorineural hearing loss (ISSHL) of aged people. Objectives: The aim of this study is to analyze the characteristics, treatment, and prognostic factors of ISSHL in aged people. Material and methods: A total of 278 patients diagnosed of ISSHL in aged people from 2014 to 2019 were retrospectively analyzed. Univariates were analyzed by univariate and multivariate logistic analysis. Results: Among the 13 univariates, the patients' age was younger in the overall recovery group ORG (p = .018), while onset days was shorter in ORG (p = .000). The percentage of DM and HTN comorbidities were higher in ORG (p = .026 and .038). Meanwhile differences were significant in audiogram configurations (p = .037), the degree of hearing loss (p = .033), and types of lipid treatment (p = .020). Then these seven independent risk factors were included in the multivariate analysis, final results indicated that hypertension (p = .028), lipid control groups (p = .009), age (p = .000), and onset days (p = .001) were related to the treatment outcome of ISSHL. Conclusions: The prognosis of ISSHL in aged patients was closely related to age, the onset days of treatment, and good control of complications such as hypertension and hyperlipidemia, so vascular factors were considered as the main causes of morbidity.

Association of Metabolic Syndrome With Sudden Sensorineural Hearing Loss

Importance

Each of the 5 diagnostic criteria or factors of metabolic syndrome-hyperglycemia or type 2 diabetes, hypertension, obesity, elevated triglyceride levels, and decreased high-density lipoprotein cholesterol level-is associated with the pathophysiologic features of sudden sensorineural hearing loss (SSNHL). Little is known, however, about the association of metabolic syndrome, defined as the presence of at least 3 of these factors, with the prognosis of SSNHL.

Objective

To evaluate the association of metabolic syndrome with the rate of recovery from SSNHL.

Design, Setting, and Participants

This retrospective medical record review of 124 patients treated for SSNHL at a single tertiary university hospital was performed from June 1, 2014, through May 31, 2016. Medical records were reviewed for demographic and clinical characteristics and audiologic variables.

Exposure

Sudden sensorineural hearing loss.

Main Outcomes and Measures

Correlation among demographic and clinical characteristics, audiologic results, and prognosis.

Results

Of the total 124 patients (52 men [41.9%]; 72 women [58.1%]; mean [SD] age, 56.0 [14.6] years), 70 had metabolic syndrome and 54 did not. Rates of type 2 diabetes (36 [51.4%] vs 6 [11.1%]; mean difference [MD], 40.3%; 95% CI, 24.4%-53.1%), hypertension (46 [65.7%] vs 9 [16.7%]; MD, 49.1%; 95% CI, 32.3%-61.7%), and obesity (47 [67.1%] vs 6 [11.1%]; MD%, 56.0; 95% CI, 40.0%-67.5%) and mean (SD) concentrations of triglycerides (192.9 [159.7] vs 133.4 [116.6] mg/dL; MD, 59.4 mg/dL; 95% CI, 53.0-65.9 mg/dL) were significantly higher and mean (SD) concentrations of high-density lipoprotein cholesterol (45.8 [9.4] vs 62.6 [17.7] mg/dL; MD, 16.8 mg/dL; 95% CI, 16.1-17.4 mg/dL) were significantly lower in the group with metabolic syndrome than in the group without metabolic syndrome. Mean (SD) pure-tone audiometry thresholds were similar at baseline in the groups with and without metabolic syndrome (65.0 [24.2] vs 60.8 [24.2] dB; MD, 4.3 dB; 95% CI, 3.2-5.4 dB), but recovery rates after treatment were significantly lower in the group with metabolic syndrome (16 [22.9%] vs 23 [42.6%]; MD, -19.7%; 95% CI, -35.4% to -3.2%). No differences were found in the 5 factors among patients with metabolic syndrome who did and did not recover. Level of hearing loss was higher in patients with than without metabolic syndrome, but the difference was not statistically significant. Audiogram patterns also differed but not significantly. Hearing recovery rates were similar in patients with 3 factors of metabolic syndrome and those with none but differed significantly between patients with 4 or more factors and those without metabolic syndrome (4 [19.0%] vs 27 [50.0%]; MD, -31.0%; 95% CI, -48.1% to -6.4%).

Conclusions and Relevance

The rate of recovery from SSNHL was lower among patients with metabolic syndrome than among those without metabolic syndrome, and prognosis was poorer in patients with 4 or more diagnostic factors of the metabolic syndrome.

Current concepts in the management of idiopathic sudden sensorineural hearing loss

PURPOSE OF REVIEW

The purpose of this manuscript is to review the initial management strategies for idiopathic sudden sensorineural hearing loss, with an emphasis on the role that steroids play in treatment of this condition, and discuss options for auditory rehabilitation of persistent unilateral hearing loss.

RECENT FINDINGS

Recent data suggest that hearing improvement may be greater for patients initially treated with both systemic and intratympanic steroid when compared with those treated with systemic steroids alone. Salvage intratympanic steroids have been shown to confer hearing benefit if initial management fails. The ideal dosing regimen for intratympanic steroids has not been established, but evidence supports that higher dosing strategies are advantageous. Cochlear implantation has emerged as a strategy for auditory rehabilitation of persistent unilateral hearing loss. Recent studies have demonstrated high patient satisfaction, subjective improvement in tinnitus, and objective performance benefit after cochlear implantation for single-sided deafness.

SUMMARY

Patients can be offered steroid therapy in the initial management of idiopathic sudden sensorineural hearing loss, but should be counseled that the efficacy of steroids remains unclear. If patients fail to improve with initial management, salvage intratympanic steroid administration should be considered. If hearing loss persists long term, options for auditory rehabilitation should be discussed.