Metabolic syndrome and idiopathic sudden sensori-neural hearing loss

The role of serun lipid, cytokine production in sudden sensorineural hearing loss

Sudden sensorineural hearing loss (SSNHL) has serious harm to human hearing health, where blood lipid and inflammatory levels may play a key role in it. Thus, the purpose of this investigation was to assess the connection between inflammatory and lipid variables and SSNHL. Patients diagnosed with SSNHL had an analysis of serum lipid parameters, such as total cholesterol (TC), triglycerides, HDL-C, LDL-C, apolipoprotein A (apo A), apolipoprotein B (apo B), and lipoprotein A (Lp(a)), as well as inflammatory factors like TNF-α and IL-10. After that, risk factor analysis was carried out utilizing univariate, multivariate regression, and LASSO retrospective modeling. In all, 72 SSNHL patients and 67 healthy control individuals were involved. The LDL/HDL, total cholesterol, ApoB, LP(a), IL-10, TNF-α, and IFN-γ considerably higher in the SSNHL group than in the healthy control group, however, nervonic acid and coenzyme Q were decreased significantly in SSNHL than Control group. The multivariate logistic regression model's analysis using multifactorial retrospective modeling revealed significant changes in LDL, LDL/HDL, IL-10, and TNF-α. In addition, in the LASSO regression model, the model demonstrated high discrimination, as evidenced by the C-index for the cohort's prediction nomogram, which was 0.998 (95% CI, 0.154-1.115) and confirmed to be 0.925 following bootstrapping validation. Finally, IL-10 and LDL/HDL were the main risk factors in SSNHL. LDL/HDL and IL-10 may be closely related to SSNHL's progress and should be evaluated promptly before treating patients with SSNHL.

Sudden sensorineural hearing loss in diabetes mellitus patients receiving intra-tympanic steroid injections

BACKGROUND

Sudden sensorineural hearing loss is an acute hearing disorder typically managed using steroids. However, prognostic factors of diabetes mellitus (DM) patients undergoing intra-tympanic steroid injections (ITSIs) are unclear. We explored the prognostic factors for ITSI in DM patients with unilateral SSNHL.

METHODS

This retrospective study enrolled 89 DM patients with unilateral SSNHL from July 2016 to June 2022. All patients received ITSIs, and their clinical and audiological data were analyzed.

RESULTS

The patients' mean age was 49.31 ± 16.26 years. After ITSI, the mean hearing level gain was 14.91 ± 20.28 dB, the mean speech reception threshold (SRT) gain was 15.78 ± 32.16 dB, and the mean speech discrimination score (SDS) gain was 16.94 ± 35.06 %. Based on Siegel's criteria, 8 patients (8.98 %) had complete recovery, 14 (15.73 %) had partial recovery, 16 (17.98 %) had slight recovery, and 51 (57.31 %) had no improvement. Older age (odds ratio [OR] = 0.970, 95 % confidence interval [CI]: 0.941-0.999, p = 0.043) and profound hearing loss on pure-tone audiometry (PTA; OR = 0.058, 95 % CI: 0.007-0.462, p < 0.001) were adverse prognostic factors in univariate analyses. Older age (OR = 0.963, 95 % CI: 0.932-0.994, p = 0.023) and profound hearing loss (OR = 0.048, 95 % CI: 0.005-0.395, p = 0.004) were independent negative prognostic factors in a multivariate analysis.

CONCLUSIONS

ITSI is effective and avoids side effects of high-dose steroids in patients with SSNHL and DM. Among 89 DM SSNHL patients who underwent ITSI, older age and profound hearing loss were negative prognostic factors. Prompt and active management is necessary for DM patients with these risk factors.

Associations of Blood Lipids with the Risk and Prognosis of Sudden Sensorineural Hearing Loss: A Meta-analysis

Patients with sudden sensorineural hearing loss (SSNHL) may lose their hearing. The relationship between SSNHL and total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels is still unclear. The association of TC, TG, HDL-C, and LDL-C levels with the risk and prognosis of SSNHL was explored in this study. After searching for literature in different databases, 13 researches were used to summarize the risk and prognosis of SSNHL associations with TC, TG, HDL-C, and LDL-C using meta-analysis. Total cholesterol had a significant association with the risk of SSNHL (95% CI, 1.34-2.91). Adjustment for confounding factors and grouping criteria of TG were all significant sources of heterogeneity. One of the significant sources of heterogeneity in the LDL-C subgroup analyses was an adjustment for confounders. Sensitivity analysis revealed a robust association between TC and the risk of SSNHL. There was a significant publication bias in the association between TC and SSNHL prognosis High TC level is a risk factor for SSNHL.

Predicting Sudden Sensorineural Hearing Loss Recovery with Patient-Personalized Seigel's Criteria Using Machine Learning

BACKGROUND

Accurate prognostic prediction is crucial for managing Idiopathic Sudden Sensorineural Hearing Loss (ISSHL). Previous studies developing ISSHL prognosis models often overlooked individual variability in hearing damage by relying on fixed frequency domains. This study aims to develop models predicting ISSHL prognosis one month after treatment, focusing on patient-specific hearing impairments.

METHODS

Patient-Personalized Seigel's Criteria (PPSC) were developed considering patient-specific hearing impairment related to ISSHL criteria. We performed a statistical test to assess the shift in the recovery assessment when applying PPSC. The utilized dataset of 581 patients comprised demographic information, health records, laboratory testing, onset and treatment, and hearing levels. To reduce the model's reliance on hearing level features, we used only the averages of hearing levels of the impaired frequencies. Then, model development, evaluation, and interpretation proceeded.

RESULTS

The chi-square test (p-value: 0.106) indicated that the shift in recovery assessment is not statistically significant. The soft-voting ensemble model was most effective, achieving an Area Under the Receiver Operating Characteristic Curve (AUROC) of 0.864 (95% CI: 0.801-0.927), with model interpretation based on the SHapley Additive exPlanations value.

CONCLUSIONS

With PPSC, providing a hearing assessment comparable to traditional Seigel's criteria, the developed models successfully predicted ISSHL recovery one month post-treatment by considering patient-specific impairments.

Effect of statins on hearing outcome in patients with idiopathic sudden sensorineural hearing loss

Objective

Statins have been reported to improve vascular endothelial function and microcirculation, reduce oxidative stress, and exert anti-inflammatory and protective effects against inner ear damage. Therefore, this study aimed to investigate the effect of statins on hearing prognosis in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

Methods

We reviewed the medical records of 149 patients diagnosed with ISSNHL. Clinical characteristics, hearing thresholds, statin medications, and hematological findings were investigated. First, patients with ISSNHL were assigned to the good and poor outcome groups, and factors influencing their prognosis were analyzed. Furthermore, patients with dyslipidemia were investigated to determine whether statins have therapeutic effects on ISSNHL.

Results

Significant differences in age (p = .011), days from the onset of ISSNHL to the initiation of treatment (p = .04), and hematological total cholesterol (TC; p = .015) between the good and poor outcome groups were observed. Furthermore, when hearing outcomes were investigated in patients with dyslipidemia, TC was significantly lower in the good outcome group (p = .03). Although no significant therapeutic effects of statins were observed in participants with dyslipidemia, patients in the statin-treated group were significantly older and experienced more diabetic complications than those in the non-statin-treated group.

Conclusion

Although our study showed that dyslipidemia is a poor prognostic factor for ISSNHL, statins had no significant therapeutic effects on hearing recovery in ISSNHL patients with dyslipidemia. The patients that received statin medications were significantly older and experienced more diabetic complications, which may have affected their hearing prognosis.

Level of Evidence

Level 4.

Endothelial Dysfunction and Metabolic Disorders in Patients with Sudden Sensorineural Hearing Loss

Sudden sensorineural hearing loss (SSNHL) is defined as a sensorineural hearing loss of 30 dB or greater on at least three contiguous audiometric frequencies occurring within a 72 h period. Although SSNHL is commonly encountered in clinical audiology and otolaryngology practice, its etiopathogenesis continues to be poorly understood. Scientific investigations have highlighted the vulnerability of cochlear microcirculation to blood flow alterations. Even mild hypoperfusion can lead to immediate dysfunction in the organ of Corti, given the heightened susceptibility of cochlear hair cells to hypoxia and ischemic damage. The purpose of this review paper is to present evidence of endothelial and vascular involvement in SSNHL and the risk factors, such as metabolic syndrome, that may negatively impact the inner ear's vascular supply, influencing the onset pattern, incidence, and prognosis of SSNHL. By addressing these variables, we can deepen our comprehension of the mechanisms underlying SSNHL and potentially uncover strategies for prevention.

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.

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

OBJECTIVES/HYPOTHESIS

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

METHODS

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

RESULTS

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

CONCLUSION

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

LEVEL OF EVIDENCE

NA Laryngoscope, 133:15-24, 2023.

Association between atherosclerosis, hearing recovery, and hearing in the healthy ear in idiopathic sudden sensorineural hearing loss: a retrospective chart analysis

Atherosclerosis is reported to be a risk factor for the severity of idiopathic sudden sensorineural hearing loss (ISSNHL). We evaluated the hypothesis that atherosclerosis affects the hearing thresholds of both the affected and healthy sides of ISSNHL patients. We conducted multivariate analyses on retrospectively collected data of patients with ISSNHL (N = 762) to evaluate the relationship between known factors linked to atherosclerosis and hearing thresholds on affected and healthy sides and whether these factors are prognostic for hearing recovery. Older ages, vertigo or dizziness, diabetes mellitus, and congestive heart failure were significantly related to higher hearing thresholds on the affected side. Older ages, male, and vascular disease were significantly related to higher hearing thresholds on the healthy side. Vertigo or dizziness, severe hearing loss and hearing loss at high frequencies on the affected side, higher hearing thresholds on the healthy side, regular anticoagulant medication, and delayed steroid treatment were significantly related to lack of recovery. Since several atherosclerosis-related factors are associated with higher hearing thresholds on both affected and healthy sides in ISSNHL and higher hearing thresholds on the healthy side predict poorer prognosis, diagnosis, and predicting prognosis of ISSNHL may benefit from rigorous evaluation of patients' cardiovascular comorbidities and hearing levels on both the healthy and affected sides.