Evaluating the Role of Triglyceride–Glucose Index in Sudden Hearing Loss

Evaluating the Role of Triglyceride–Glucose Index in Sudden Hearing Loss | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Evaluating the Role of Triglyceride–Glucose Index in Sudden Hearing Loss Ahmet Aksoy, Tuba Doğan Karataş This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8013375/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 6 You are reading this latest preprint version Abstract Objective This study aimed to retrospectively evaluate triglyceride-glucose (TyG) index levels in patients with sudden sensorineural hearing loss (SSNHL) and explore its potential as a biomarker for early diagnosis or risk prediction. Methods This retrospective study included patients aged 18 years who were diagnosed with SSNHL from 2017 to 2024 following institutional ethics approval (2025-01/164). Complete fasting triglyceride (TG), fasting plasma glucose (FPG), and audiometric data (baseline and 3-month pure tone averages) were required for eligibility. Patients with a history of chronic otitis media, otosclerosis, meniere’s disease, or prior ear surgery were excluded from the study. Hearing thresholds of 500, 1000, 2000, and 4000 Hz were evaluated using the modified Siegel criteria. Statistical analyses were performed using R (version 4.4.1) and JASP (version 0.19.0), with p < 0.05 considered statistically significant. Results A total of 396 patients were included, with 50% serving as the control group. No significant differences in age, sex, glucose, or TG levels were observed between the groups. However, the SSNHL group had significantly higher TyG index values (p < 0.001). The TyG index was strongly associated with the severity and recovery of hearing loss, as determined by the modified Siegel criteria (p < 0.001), and was positively correlated with hearing thresholds across frequencies. TyG was identified as an independent risk factor for SSNHL (Odds ratio = 0.55; p < 0.001). However, the ROC analysis revealed limited discriminatory capacity (AUC = 0.619), indicating that TyG may not be a sufficient standalone diagnostic marker. Conclusion This study is among the first to analyze the relationship between SSHL and the TyG index. The TyG index was identified as an independent risk factor for SSNHL and may serve as a potential predictive biomarker, particularly within multivariate models. Triglyceride–Glucose Index Sudden Hearing Loss Biomarker Otological emergency Figures Figure 1 Figure 2 Introduction Sudden sensorineural hearing loss (SSNHL) is a sudden-onset hearing disorder that usually develops unilaterally in three days and is characterized by a sensorineural loss of > 30 dB in three sequential frequencies [1, 2]. Etiology can be determined in only a small proportion of cases (10–15%), and most cases are idiopathic. Although the underlying mechanisms of SSNHL are not clearly understood, systemic factors, such as vascular insufficiency, metabolic imbalance, and thrombotic tendency, may contribute to the disease process [2, 3]. Because the blood supply to the inner ear is limited to the terminal arteries and the inner ear requires a high level of energy, it becomes very sensitive to circulatory and biochemical changes. In this context, fluctuations in glucose and insulin as well as disorders of lipid metabolism may have negative effects on the cochlear function. Hence, some studies have demonstrated that serum cholesterol can be significantly related to SSNHL, and it can be considered a potential risk factor [ 4 , 5 ]. Although the mechanism by which hyperglycemia leads to sudden hearing loss (SHL) is unclear, in vivo experimental data suggest that fluctuations in serum glucose levels can impair the motility and function of outer hair cells by affecting the serum osmolarity, resulting in negative effects on cochlear microphonic activity [ 6 , 7 ]. Irregularities in lipid metabolism may impair cell function by leading to lipid accumulation in cochlear hair cells, resulting in abnormal auditory conduction over structural damage in cochlear nerve signaling pathways [ 8 ]. The triglyceride–glucose (TyG) index is regarded as a more practical, low-cost alternative, which is also independent from insulin levels, to the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) in evaluation of the insulin resistance [ 9 – 11 ]. Recent studies showed that the TyG index is related with cardiometabolic diseases, neurovascular conditions, and sleep disorders [ 12 – 14 ]. Liu et al. reviewed relation of the TyG index with various types of hearing loss (HL) [ 15 ]. In this context, this study aims to examine the relationship of the TyG index with the SSNHL, which is addressed in limited studies in the literature, and to reveal the possible role of this index as a potential metabolic risk marker. Material-Method After obtaining approval from the institutional ethics committee (2025-01/164), this retrospective study enrolled patients aged >18 years who were diagnosed with SSNHL in our clinic from 2017 to 2024. This study reviewed the demographics, biochemical parameters (triglyceride and glucose), and hearing functions (pure tone audiogram data at diagnosis and month-3 follow-up) of patients. The inclusion criteria of the study were as follows: age >18 years, history of sudden HL, presence of routine biochemical test results, including fasting triglyceride (TG) and fasting plasma glucose (FPG), and audiological test results as well as comprehensive otolaryngological examination. We excluded patients with a history of another ear disease, those diagnosed with otosclerosis or Meniere’s disease, and those with tympanic membrane or external auditory canal pathology in otoscopic examination, are excluded. Measurement of the TyG Index The TyG index was calculated using the following formula: TyG index = In [TG (mg/dL) × FPG (mg/dL) / 2] TG and FPG levels were measured using automatic biochemistry analyzers and the enzymatic analysis method. The TG concentration was measured using the Roche Modular P and Roche Cobas 6000 chemistry analyzers. The FPG concentration was measured using a chemistry analyzer (Roche/Hitas Cobas C 501) that operated using the hexokinase-mediated reaction method. Audiological Evaluation Audiology tests are conducted in sound-insulated rooms. Otoscopic examination and tympanometry rule out pathologies of the outer and middle ear in all patients. Pure-tone audiometry tests were performed using an Interacoustics brand AC40 audiometry device, TDH-39 model supra-aural headphones that are integrated to the audiometry device, and bone vibrator in cabinets that meet standards of acoustic measurements. The air-conduction hearing threshold is 250-8000 Hz and bone conduction hearing threshold is 500-4000 Hz in both ears. The mean air and bone conduction pure sound frequencies were calculated using arithmetic averages of hearing thresholds at frequencies of 500, 1000, and 2000 Hz. Hearing loss examination is based on the Clark classification. The modified Siegeal criteria were used to evaluate hearing level during the follow-up and control periods (Table I). The MAICO MI 44 Analyzer (MAICO Diagnostic GmbH, Salzufer 13/14, D-10587 Berlin, Germany) was used for tympanometric examination. A stimulus (frequency = 226 Hz and SPL = 85 dB) was sent during the examination. Tympanogram curves were obtained using a probe inserted into the external acoustic canal by changing the air pressure from +200 daPa to -400 daPa. Table I. Examination of hearing level according to the Modified Siegel criteria before and after treatment Examination of hearing level according to Modified Siegel criteria before and after treatment Grading by mean pure tone threshold before treatment Grade 1 Mean Hearing Thresholds ≤25 dB HL Grade 2 Mean Hearing Thresholds 26-40 dB HL Grade 3 Mean Hearing Thresholds 46-75 dB HL Grade 4 Mean Hearing Thresholds 76-90 dB HL Grade 5 Mean Hearing Thresholds >90 dB HL, Examination by mean pure tone threshold after treatment (1) Complete Recovery Final Hearing Level ≤25 dB HL (2) Partial Recovery Hearing gain >15 dB and final hearing level 26-45 dB (3) Mild Recovery hearing gain >15 dB and final hearing level 46-75 dB (4) No Recovery hearing gain 90 dB Results Considering 396 cases who are enrolled to the study, 50% of patients (n= 198) represented the control group and other 50% (n= 198) created the SSNHL group. There was no statistically significant difference between two groups in terms of distribution of sex (p= 0.382). Distribution of sexes in groups is homogeneous. Participants of the SSNHL group were older than the patients of the control group and a significant difference is found (p= 0.013). Glucose level is significantly higher in the SSNHL group and a significant difference is observed (p=<0.001). There was no significant difference in TG levels between the groups (p = 0.301), but the TyG index was significantly higher in the SSNHL group than in the SSNHL group (p=<0.001). This result demonstrates that the TyG index is higher in the SSNHL group and that the TyG index correlates with the SSNHL (Table II). Table II. Comparison of the control and sudden hearing loss groups in terms of demographics and metabolic parameters Variables Control group Sudden hearing loss group p Sex, n(%) Male 99(50.0) 103(52.0) 0.382 * Female 99(50.0) 95(48.0) Age 49.26 ±14.76 53.64±15.40 0.013 & Glucose 98.58±23.72 116.07±54.59 <0.001 & Triglyceride 125.99±65.98 175.71±134.70 0.301 & TyG Index 8.58±0.59 8.92±0.84 <0.001 & * : Chi-Square test, & : Mann–Whitney U test Patients were assigned to study groups according to the level of HL before and after treatment; Table III shows the comparative results of the descriptive statistics of the TyG index levels. Statistically significant differences in the TyG index were found between patients assigned to study groups according to the level of HL before treatment; an obvious increase is observed particularly in patients with advanced stage disease (p<0.001). This result suggests that the TyG index is related to the severity of the disease. Significant differences were found between the study groups by recovery level after treatment in terms of the TyG index, and the differences between the group with full recovery and other groups demonstrate that the index can be related to the clinical process and it may reflect the metabolic changes in early grade (p<0.001). Table III. Descriptive statistics of the triglyceride–glucose index levels in patients assigned to study groups according to the level of hearing loss before and after treatment and results of multiple comparisons Level of hearing loss before treatment TyG Recovery level according to the mean result of pure tone audiometry after treatment TyG Grade 1 8.61±0.92 8.57(5.81-11.57) 1 8.60±0.78 8.57(5.81-11.57) Grade 2 8.82±0.68 8.79(7.58-11.27) 2 9.11±0.76 9.02(7.72-10.91) Grade 3 8.96±0.89 8.78(7.62-11.04) 3 9.01±0.87 8.85(7.58-11.04) Grade 4 9.04±0.87 8.97(7.85-11.63) 4 9.34±0.82 9.30(7.96-11.63) Grade 5 9.56±0.68 9.66(8.05-11.04) 5 9.35±0.87 9.52(7.62-11.04) p & <0.001 p & <0.001 p 1-2 0.127 p 1-2 <0.001 p 1-3 0.104 p 1-3 0.028 p 1-4 0.074 p 1-4 <0.001 p 1-5 <0.001 p 1-5 <0.001 p 2-3 0.580 p 2-3 0.539 p 2-4 0.357 p 2-4 0.294 p 2-5 <0.001 p 2-5 0.257 p 3-4 0.679 p 3-4 0.202 p 3-5 0.003 p 3-5 0.193 p 4-5 0.013 p 4-5 0.748 & : Kruskal–Wallis test, p 1-2 , p 1-3 , p 1-4 , p 1-5 , p 2-3 , p 2-4 , p 2-5 , p 3-4 , p 3-5 , p 4-5 : Mann–Whitney U test is used for paired comparisons, while Bonferroni correction is performed to minimize the risk of type I error in multiple comparisons. In this context, the level of significance was set at 0.05/10 = 0.005. The present study investigates the potential association between the TyG index and a series of audiometric and acoustic metrics. Spearman correlation analysis revealed significant positive relationships between the TyG index and multiple acoustic parameters (p<0.05). The mean air conduction values in the right and left ears were significantly correlated with the TyG index before and after treatment. Correlations between mean air conduction values of right and left ears, particularly before treatment, are intermediate, the effect of metabolic dysfunction on peripheral acoustic responses. This reveals that the TyG index-related acoustic changes are particularly remarkable at high frequencies (rho=0.25–0.33, p<0.001). These results demonstrate that the TyG index is not only a marker of the systemic metabolic condition but may also have significant effects on the hearing system In the logistic regression analysis that is performed to determine the variables that can be related to sudden sensorineural hearing loss, univariate analyses are primarily performed and next, logistic regression analysis is performed, where the TyG index is added to the multivariate model, in addition to age and sex variables (Table IV). These results demonstrate that each increment in the TyG index increased the odds of SHL by approximately 0.5-fold. When age and sex variables were included in the multivariate analysis, sex and age did not have an independent effect, but the positive correlation of the TyG index with the SSNHL was still significant (Figure I). These results reveal that the TyG index can be a significant risk marker in the development of SSNHL independent of age and sex. Excluding the effects of age and sex supports the quality of the TyG index as an independent predictor. The relationship of the TyG index with insulin resistance and microvascular effects amplify the association of this biomarker with sudden vascular events, such as SHL. Table IV. Results of univariate and multivariate logistic regression analysis of variables related to sudden hearing loss. Variables Univariate OR (95% CI) p Multivariate OR (95% CI) p Sex, (Male) 1.08(0.73-1.60) 0.688 0.93(0.63-1.40) 0.711 Age, (years) 0.98(0.97-0.99) 0.005 0.99(0.98-1.06) 0.234 TyG Index 0.51(0.38-0.69) <0.001 0.55(0.39-0.75) <0.001 Abbreviations: OR = Odds Ratio; CI = Confidence Interval ROC analysis was performed to evaluate the power of the TyG index, which was included in the model because of the logistic regression analysis and significantly contributed to the prediction of SSNHL. According to the analysis results, the TyG index has low distinctiveness to predict SHL. The AUC (Area Under the Curve) that is calculated for the TyG index is 0.619 (95% CI: 0.564–0.674), and this figure is statistically significant (p<0.001). The ROC curve in Figure II shows that the TyG index has low power to distinctly identify or predict patients with and without SSNHL. The maximum optimal cutoff value determined according to the Kolmogorov-Smirnov statistics is 8.63. Sensitivity (62.3%) and specificity (57.1%) are limited in this threshold value. The Gini index that reflects the classification success of the model is 0.148, and the model’s general quality is 0.51. This value shows that the model performs slightly better than random estimation. The evaluation of hearing levels before and after treatment according to the Modified Siegel criteria is presented in Table V. When the relation between hearing scores according to mean value of pure tone audiometry before treatment and hearing scores after treatment is reviewed, a statistically significant difference is not found (p <0.001). The linear-by-linear association test also confirmed this linear relationship (test statistic = 86.210; p < 0.001). These findings indicate that disease severity at the time of diagnosis is a significant determinant of response to treatment. Table V. Evaluation of hearing levels before and after treatment according to the Modified Siegel criteria Groups by the mean pure tone threshold before treatment Clinical examination by mean pure tone threshold after treatment n (%) Grade 1 (n = 35, 17.7%) Complete recovery 30(85.7) Partial recovery 3(8.6) No recovery 2(5.7) Grade 2 (n = 64, 32.3%) Complete recovery 32(50.0) Partial recovery 24(37.5) Mild recovery 8(12.5) Grade 3 (n = 58, 29.3%) Complete recovery 13(22.4) Partial recovery 18(31.0) Mild recovery 21(36.2) No recovery 2(3.4) Total hearing loss 4(6.9) Grade 4 (n = 19, 9.6%) Complete recovery 5(26.3) Partial recovery 2(10.5) Mild recovery 4(21.1) No recovery 8(42.1) Grade 5 (n = 22, 11.1%) Partial recovery 2(9.1) Mild recovery 4(18.2) No recovery 5(22.7) Total hearing loss 11(50.0) p <0.001 *: Fisher-Freeman-Halton exact test. Statistical analysis Statistical analyses were performed using R (version 4.4.1, R Foundation for Statistical Computing) and JASP (version 0.19.0, University of Amsterdam, Netherlands) software. The Kolmogorov–Smirnov and Shapiro–Wilk tests were employed to analyze the continuous variable’s distribution characteristics. The descriptive statistics of the variables are expressed as mean ± standard deviation, median (minimum – maximum), and frequency (n, %). Paired comparisons are analyzed with the Mann–Whitney U test if the normality assumption is not ensured. When three or more groups are compared, ANOVA and Kruskal–Wallis tests are used. Paired comparisons were performed using the Mann–Whitney U test and Bonferroni correction is applied to compare the groups with significant differences as a result of the Kruskal–Wallis test. In this context, the significance level was set at 0.05/10 = 0.005. For the comparison of categorical variables, the chi-square test and Fisher Freeman-Halton Exact tests are used by considering cross tabulation and expected cell frequencies. Logistic regression analysis was performed to determine the factors that are effective in the development of SSNHL. The relationship between the TyG index and acoustic parameters are examined with the Spearman correlation analysis. Receiver operating characteristic (ROC) curve analysis was performed to determine whether the TyG index, which had a significant effect on the risk of SSNHL in the logistic regression analysis, has a diagnostic value to predict the presence of SSNHL. Statistical significance level is p<0.05 in all analyses. Discussion The TyG index is a practical parameter that can detect metabolic signals, which indicate insulin resistance, without requiring complex laboratory tests, only because it can be calculated with FPG and TG levels. In this aspect, it is a potential biomarker that can contribute to the prediction of early metabolic dysfunctions for large-scale population screenings and in clinical settings with limited resources [16]. According to the results of the multivariate logistic regression analysis performed in this study, the TyG index is an independent risk factor for SHL. This finding demonstrates that the TyG index plays a role in pathophysiology of the SHL as an indicator of metabolic dysfunction. The association between the TyG index and both insulin resistance and microvascular impairment supports its role in cochlear vascular insufficiency-mediated HL. However, because the AUC value is limited to 0.619, according to the ROC analysis result, the TyG index does not have sufficient performance as a diagnostic tool alone. The shape of the receiver operating characteristic (ROC) curve and its proximity to the diagonal reference line demonstrate that the index makes a limited contribution in terms of sensitivity and specificity. However, the limited diagnostic power observed in the ROC analysis should not overshadow the significance in the regression analysis because the TyG index can be a biomarker that reflects metabolic disorders, which pave the way for development of the disease, rather than diagnosis. In this context, the predictive role of the TyG index should not be ignored, and the potential of the index in multivariate models, where other variables of this parameters are used, should be more comprehensively investigated in advanced studies. Lisowska et al. reported that changes in cochlear micro-mechanics and retrocochlear auditory pathways manifest as subclinical hearing disorder in patients with diabetes mellitus [17]. In vitro studies revealed that glucose is used intensely in the development of the cochlea and that inner and outer hair cells are sensitive to oxygen and glucose deficiencies [18, 19]. Amarjargal et al. reported that the loss of hair cells occurs under conditions of glucose deficiency, and inner hair cells are more sensitive than outer hair cells [19]. These findings are also supported by epidemiological evidences obtained by the American National Health Research, which revealed that adults with diabetes mellitus (21.3%) have more HL than those without (9.4%) [20]. In a 30-year epidemiological study conducted in Japan, the SHL tendencies were evaluated, and it was clarified that the number of patients with sensorineural hearing loss increased from 4000 in 1972 to 35000 in 2001, an increment of more than eight folds. One of the outstanding findings of this study is the recent significant increase in the prevalence of diabetes mellitus in patients with the SHL in comparison with date of the initial period [21]. Results of experimental studies reveal that hyperlipidemia (HL) has a significant effect on auditory functions [22, 23]. Experimental chronic hypercholesterolemia leads to accumulation of glucose in the cochlea by causing metabolic stress in the inner ear tissue, resulting in stria vascularis and edema in the outer hair cells [22]. These changes occur principally in the basal cochlear turn and are related to the loss of hearing sensitivity found in the auditory brainstem response (ABR) secondary to cholesterol-rich diet. In a case – control study that examined the results of audiometry, ABR, and transient evoked oto-acoustic emission (TEOAE) in patients with hypercholesterolemia and hypertrygliceridemia, a significant difference was not found in mean hearing thresholds of the study and the control groups [5]. The literature had comprehensively addressed the role of lipids in pathogenesis of the sensorineural hearing loss (SNHL). The cochlea is an end organ that needs continuous nutrient and oxygen flow to continue its physiological functions, and it is substantially sensitive to circulatory changes [24]. High blood viscosity can decrease the blood supply to the inner ear, potentially resulting in injury to the inner ear [25]. Hyperlipidemia is a common condition in patients with SSNHL [8, 26]. Dietary approach and lipid-lowering treatment can be related to HL recovery [27]. Recent studies have revealed that inflammatory diseases, such as diabetes mellitus and cardiovascular disease, are proven risk factors for hyperlipidemia [28]. Moreover, various components of the metabolic syndrome, including high blood pressure and dyslipidemia, have relations with the HL [29]. Although there is sufficient principal research evidence to prove these risk factors of the pathogenic process, biomarkers with better correlation are still required for the SNHL. In a national-scale study conducted by Liu et al. based on the NHANEs data, the prevalence of HL is higher in people with higher TyG index and that this relation is significant, particularly at high frequencies, and this index can be an independent risk factor for the SNHL (OR = 1.12, 95% GA: 1.03–1.22) [15]. Pan et al. determined determined a relation with the “U” configuration between the TyG index, speaking and hearing thresholds with high frequency and they found that this relation reverses above certain hearing thresholds and impairs the hearing function [30]. Wang et al. conducted a cross-sectional and Mendelian randomized study and demonstrated that the risk of SSNHL increases significantly in people with TyG index above 9.07 (HR: 3.60, 95% GA: 1.42–9.14) and that genetically determined high triglyceride levels correlate with the increased risk of sensorineural hearing loss [31]. In addition, Amaral et al. found changes in systemic inflammation markers, such as adiponectin, TNF-α and IFN-γ, in patients with SSNHL and suggested that these changes can be related to hearing recovery [32]. This finding demonstrates that metabolic and inflammatory processes play a joint role in the pathophysiology of HL. In experimental studies that are conducted on animal models, electrophysiological dysfunction and a significant increase in oxidative stress markers were observed in the auditory tracts of rats that are exposed to hyperglycemia [33]. This also supports the idea that glucose fluctuations may lead to cochlear injury even in the prediabetic period. The TyG index is also related to cognitive dysfunctions and dementia. This condition suggests that systemic microvascular dysfunctions may be effective not only at the cerebral level but also at the cochlear level [9]. On the other hand, the effect of the components of the metabolic syndrome, such as diabetes mellitus and insulin, on hearing health is strongly supported in the literature. Bainbridge et al. reported that HL in both low and high frequencies is significantly more common in people with diabetes mellitus [20]. Experimental studies have reported histopathological changes in the inner ear, particularly outer hair cells, secondary to dyslipidemia [22, 29]. Kojima et al. reported significant hearing recovery in patients with late-stage SSNHL after treatment of the HL. Circulatory recovery may support hearing function [27]. Kaneva et al. emphasized that the atherogenic index can be used as a predictive biomarker for SSNHL and that a high atherogenic load can increase the risk even if conventional lipid parameters are normal [8]. Lee et al. reported that high total cholesterol and triglyceride levels as wandsity increase the incidence of SSNHL, and the treatment response is poorer in these individuals than in those without [25]. Finally, although the current guidelines express that SSNHL is mostly idiopathic, they also highlight the need to investigate the underlying vascular factors [28]. Subclinical auditory changes secondary to insulin resistance are at detectable level in otoacoustic emission and auditory brain stem potentials, and these findings are significant in terms of the importance of regulating blood glucose at the cochlear level [17]. It has been reported that auditory conduction slows down significantly in both peripheral and central nervous pathways in patients with type I and type II diabetes mellitus [34]. Vascular and thrombophilic risk factors are also important in development of the SSNHL. Marcucci et al. determined that anticardiolipin antibodies and elevated PAI-1 and homocysteine levels are significantly associated with SSNHL, which can trigger microcirculatory dysfunction and coagulopathy [4]. Hearing loss is also induced in a cochlear ischemia–reperfusion model in experimental animal studies, and antioxidative agents reduce the injury [24]. Perez et al. reported apparent vestibular and cochlear dysfunctions and higher latency and lower amplitude in vestibular evoked potentials in animal models of type 2 diabetes; these findings demonstrate the direct neurotoxic effects of glycemic dysregulation on the inner ear [7]. Qatar et al. conducted an experimental study on rats exposed to hypertriglyceridemia and found stria vascularis, obvious edema in hair cells, cellular degeneration, and increased hearing threshold [23]. Microcirculatory dysfunction secondary to dyslipidemia can lead to CI. Teranishi et al. conducted a 30-year epidemiological study in Japan and reported that the incidence of SHL is increasing, and the increment is more remarkable in people with hypertension and diabetes mellitus [21]. These data strengthen the role of metabolic diseases in etiopathogenesis of the SSNHL. Our results support the idea that the TyG index is an independent risk factor for SSNHL and has the potential to be a metabolic biomarker. However, limited diagnostic accuracy—a finding that has also been observed in previous trials—makes it difficult to use this index alone as a sufficient marker [35]. Studies conducted by Deng et al. and based on Mendel randomization analysis with two samples demonstrated that elevated TG can play a causative role in SSNHL, and the authors have emphasized that TG metabolism should be closely monitored and regulated, if required [36]. The TyG index and its derivatives (TyG-BMI, TyG-WC, and TyG-WHtR) have gained importance as practical and cost-effective biomarkers that can be used to examine insulin resistance in large populations. Nonlinear curves, particularly with the “U” configuration, have identified significant relationships between the risk and severity of coronary artery disease in patients with type II DM and H-type hypertension [37, 38]. The TyG index offers a clinical advantage because of its high applicability and lack of requirement for measuring insulin levels. It can be considered a potential risk market in diseases, such as SSNHL, where vascular and metabolic mechanisms are effective [16, 39]. The higher TyG index score in our patients with sudden hearing loss than in the control group suggests that insulin resistance and resultant metabolic disorders may play a role in the disease etiology. A large-scale study on patients with hypertension demonstrated that the TyG index is an independent predictor for all-cause mortality [12]. Similarly, high TyG index can be related to HL secondary to vascular dysfunction and metabolic stress in conditions where microvascular susceptibility, such as the SSNHL, plays a role. Hence, Wang et al. conducted a large-scale study on the Chinese population and reported that the TyG index alone is not significantly related to HL, but BMI, particularly the TYG-BMI index, is strongly correlated with HL in elderly people [40]. Kim et al. reported that the TyG index has a statistically significant correlation with high-frequency HL in middle-aged Korean women. These results support the idea that cochlear microvascular dysfunction secondary to insulin resistance may play a role in the pathophysiology of HL [41]. In this context, we aimed to show that the TyG index, an indicator of the insulin resistance, can be related to disease prognosis and may have a prognostic value. Our results reveal that treatment response is closely related to the disease presentation grade in patients with SSNHL. Patients with low grade have better treatment response, whereas those with high grade have a higher rate of irresponsiveness. In this context, early diagnosis and quick disease treatment can increase the success of treatment. Our results are consistent with the literature that supports the role of the initial hearing level in SSNHL prognosis. Moreover, significant results in the linear-by-linear association analysis show a linear relationship between grade and treatment response, which can be considered in prognostic classification. Conclusion The outcomes of this study show that the TyG index is a unique metabolic risk marker for SSNHL. This parameter that reflects the insulin resistance and microvascular function can point to the systemic processes that play a role in the pathophysiology of the HL. Despite the limited diagnostic accuracy in the ROC analysis, the significant results obtained in the multivariate analysis support the predictive value of the TyG index (). The use of this index, along with other metabolic markers in the clinical evaluation process, may contribute to the identification of high-risk individuals. The strong correlation between disease presentation grade and response to treatment emphasizes the importance of early diagnosis and treatment in terms of prognosis. In this context, the combined evaluation of the TyG index and clinical grading can enable the development of a more personalized approach for the management of SSNHL. Limitations The retrospective and single-center design of the study limits the ability to identify a causative relationship and generalize the findings. Potential confounding variables, such as diet, physical activity, and comorbidities, were not considered in the evaluation of the TyG index examination. Time-dependent changes in the index were not analyzed. Prospective, multicenter studies addressing longitudinal biomarker analyses are required. Declarations Conflict of Interest : The authors have no relevant financial or non-financial interests to disclose Ethics Committee Approval: This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Sivas Cumhuriyet University (Date: January 16, 2025/ No. 2025-01/164). Written informed consent requirement was waived due to the retrospective design. Consent for publication: Not applicable Human Ethics and Consent to Participate declarations: Not applicable Funding: The authors received no financial support for the research, authorship, and/or publication of this article. Clinical trial number: Not applicable. Author Contributions Conceptualization: Ahmet Aksoy; Tuba Doğan Karataş Methodology: Tuba doğan Karataş, Ahmet Aksoy; Formal analysis and investigation: Ahmet Aksoy; ; Writing - original draft preparation: Ahmet Aksoy; Writing - review and editing: Ahmet Aksoy; Tuba Doğan Karataş Funding acquisition: Ahmet Aksoy; Resources: Ahmet Aksoy, Tuba Doğan Karataş; Supervision: Ahmet Aksoy, Tuba Doğan Karataş Acknowledgments: The study was presented orally at the 29th International Rhinocamp Meeting, held from May 22 to 25, 2025, in Marmaris, Muğla, Turkey. References Aksoy A, Özata Güngör Ö. 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Alteration of 6-phosphofructo-1-kinase subunits during neonatal maturation of rat cochlear cells. Hear Res. 2001;151:149–156. doi:10.1016/S0378-5955(00)00222-7 Amarjargal N, Andreeva N, Gross J, Haupt H, Fuchs J, Szczepek AJ, et al. Differential vulnerability of outer and inner hair cells during and after oxygen-glucose deprivation in organotypic cultures. Physiol Res. 2008; 57(Suppl 3):117–125. doi:10.33549/physiolres.931466 Bainbridge KE, Hoffman HJ, Cowie CC. Diabetes and hearing impairment in the United States: Audiometric evidence from the NHANES. Ann Intern Med. 2008;149(1):1–10. doi:10.7326/0003-4819-149-1-200807010-00231 Teranishi M, Katayama N, Uchida Y, Tominaga M, Nakashima T. Thirty-year trends in sudden deafness from four nationwide epidemiological surveys in Japan. Acta Otolaryngol. 2007;127(12):1259–1265. doi:10.1080/00016480701242410 Gratton MA, Wright CG. Alterations of inner ear morphology in experimental hypercholesterolemia. Hear Res. 1992; 61(1–2):97–105. doi:10.1016/0378-5955(92)90040-T Satar B, Özkaptan Y, Sürücü HS, Öztürk H. Ultrastructural effects of hypercholesterolemia on the cochlea. Otol Neurotol. 2001;22(6):786–789 Onal M, Elsurer C, Selimoglu N, Yilmaz M, Erdogan E, Bengi Celik J, et al. Ozone Prevents Cochlear Damage From Ischemia-Reperfusion Injury in Guinea Pigs. Artificial organs. 2017; 41(8), 744–752. https://doi.org/10.1111/aor.12863 Lee JS, Kim DH, Lee HJ, Kim HJ, Koo JW, Choi HG, et al. Lipid profiles and obesity as potential risk factors of SSNHL. PLoS One. 2015; 10(4):e0122496. doi:10.1371/journal. pone.0122496 Suckfüll M, Thiery J, Wimmer C, Mees K, Schorn K. Hypercholesteremia and hyperfibrinogenemia in sudden deafness. Laryngo-Rhino-Otologie. 1997; 76(8):453–457. doi:10.1055/s-2007-997460 Kojima Y, Ito S, Furuya N. Hearing improvement after therapy for hyperlipidemia in patients with chronic-phase sudden deafness. Ann Otol Rhinol Laryngol. 2001;110(4):353–357. doi:10.1177/000348940111000410 Mitchell P, Gopinath B, McMahon CM, Rochtchina E, Wang JJ, Boyages SC, et al. Relationship of type 2 diabetes to age-related hearing loss. Diabet Med. 2009;26(5):483–488. doi:10.1111/j.1464-5491.2009.02710.x Evans MB, Tonini R, Shope CD, Oghalai JS, Jerger JF, Insull W Jr, et al. Dyslipidemia and auditory function. Otol Neurotol. 2006;27(5):609–614 Pan JY, Chen Y, Lin ZH, Lv B, Chen L, Feng SY. Association between triglyceride-glucose index and hearing threshold shifts of adults in the United States: NHANES 2015–2016. J Multidiscip Healthc. 2024;17:1791–1801. doi:10.2147/JMDH.S454678 Wang Y, Liu H, Nie X, Lu N, Yan S, Wang X, et al. L-shaped association of triglyceride-glucose index and sensorineural hearing loss: Results from a cross-sectional study and Mendelian randomization analysis. Front Endocrinol (Lausanne). 2024;15:1339731. doi:10.3389/fendo.2024.1339731 do Amaral JB, Peron KA, Soeiro TLT, Scott MCP, Hortense FTP, da Silva MD, et al. The inflammatory and metabolic status of patients with sudden-onset sensorineural hearing loss. Front Neurol. 2024;15:1382096. doi:10.3389/fneur.2024.1382096 Akcay G, Danısman B, Basaranlar G, Guzel P, Derin N, Derin AT. The effect of increase in blood glucose level on hearing loss. Braz J Otorhinolaryngol. 2022; 88(S3):S95–S102. doi:10.1016/j.bjorl.2022.06.003 Stachler RJ, Chandrasekhar SS, Archer SM, Rosenfeld RM, Schwartz SR, Barrs DM, et al. Clinical practice guideline: Sudden hearing loss. Otolaryngol Head Neck Surg. 2012; 146(1 Suppl):S1–S35. doi:10.1177/0194599812436449 Malagón-Soriano VA, Ledezma-Forero AJ, Espinel-Pachon CF, et al. Surrogate indices of insulin resistance using the Matsuda index as reference in adult men—a computational approach. Front Endocrinol (Lausanne). 2024; 15:1343641. doi:10.3389/fendo.2024.1343641 Deng B-Y, Zhao Y-X, Liu J-S. The effect of blood glucose and lipid risk factors on idiopathic sudden sensorineural hearing loss: A two-sample Mendelian randomization study. Braz J Otorhinolaryngol. 2025;91:101579. doi:10.1016/j.bjorl.2025.101579 Wang L, Li Z, Qiu R, Luo L, Yan X. Triglyceride–glucose index–body mass index as a predictor of coronary artery disease severity in patients with H-type hypertension across different glucose metabolic states. Diabetology & Metabolic Syndrome. 2025; 17(15). doi:10.1186/s13098-024-01568-6 Yadegar A, Mohammadi F, Seifouri K, Mokhtarpour K, Yadegar S, Bahrami HE, et al. Surrogate markers of insulin resistance and coronary artery disease in type 2 diabetes: U-shaped TyG association and insights from machine learning integration. Lipids in health and disease. 2025;24(1), 96. https://doi.org/10.1186/s12944-025-02526-5 Yousefiasl M, Soltanattar A, Ezzatollahi TA, Azami P, Alaei M, Alamdari AA, et al. Association of triglyceride-glucose index with bone mineral density and fracture: a systematic review. Diabetology & metabolic syndrome. 2025;17(1),77. https://doi.org/10.1186/s13098-025-01642-7 Wang C, Shi M, Xie L, Jiang C, Li Y, Li J, et al. Relationship between TyG-related index and hearing loss in people over 45 s in China. Frontiers in public health. 2025;13, 1506368. https://doi.org/10.3389/fpubh.2025.1506368 Kim DO, Lee Y, Lee SY, Lee JG, Yi YH, Cho YH, et al. Correlation between hearing impairment and the triglyceride-glucose index in middle-aged female based on a Korean National Health and Nutrition Examination Survey. Medicina. 2024; 60(10):1596. doi:10.3390/medicina60101596 Additional Declarations No competing interests reported. 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1","display":"","copyAsset":false,"role":"figure","size":36098,"visible":true,"origin":"","legend":"\u003cp\u003eLogistic Regression (OR=0.55, p\u0026lt;0.001)\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8013375/v1/5b07c039733af2366f3aa295.png"},{"id":98073259,"identity":"de83bad1-cf11-4f63-aa31-fc420b003568","added_by":"auto","created_at":"2025-12-12 13:22:19","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":25826,"visible":true,"origin":"","legend":"\u003cp\u003eROC curve analysis (AUC) value 0.619; 95% CI: 0.564–0.674)\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8013375/v1/ad2be62b8718f8d5c0f990ab.png"},{"id":98444575,"identity":"719d3f08-bae9-47c6-a7a0-6132cd3828f3","added_by":"auto","created_at":"2025-12-17 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Etiology can be determined in only a small proportion of cases (10\u0026ndash;15%), and most cases are idiopathic. Although the underlying mechanisms of SSNHL are not clearly understood, systemic factors, such as vascular insufficiency, metabolic imbalance, and thrombotic tendency, may contribute to the disease process [2, 3]. Because the blood supply to the inner ear is limited to the terminal arteries and the inner ear requires a high level of energy, it becomes very sensitive to circulatory and biochemical changes. In this context, fluctuations in glucose and insulin as well as disorders of lipid metabolism may have negative effects on the cochlear function. Hence, some studies have demonstrated that serum cholesterol can be significantly related to SSNHL, and it can be considered a potential risk factor [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAlthough the mechanism by which hyperglycemia leads to sudden hearing loss (SHL) is unclear, in vivo experimental data suggest that fluctuations in serum glucose levels can impair the motility and function of outer hair cells by affecting the serum osmolarity, resulting in negative effects on cochlear microphonic activity [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Irregularities in lipid metabolism may impair cell function by leading to lipid accumulation in cochlear hair cells, resulting in abnormal auditory conduction over structural damage in cochlear nerve signaling pathways [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The triglyceride\u0026ndash;glucose (TyG) index is regarded as a more practical, low-cost alternative, which is also independent from insulin levels, to the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) in evaluation of the insulin resistance [\u003cspan additionalcitationids=\"CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Recent studies showed that the TyG index is related with cardiometabolic diseases, neurovascular conditions, and sleep disorders [\u003cspan additionalcitationids=\"CR13\" citationid=\"CR11\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Liu et al. reviewed relation of the TyG index with various types of hearing loss (HL) [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn this context, this study aims to examine the relationship of the TyG index with the SSNHL, which is addressed in limited studies in the literature, and to reveal the possible role of this index as a potential metabolic risk marker.\u003c/p\u003e"},{"header":"Material-Method","content":"\u003cp\u003eAfter obtaining approval from the institutional ethics committee (2025-01/164), this retrospective study enrolled patients aged \u0026gt;18 years who were diagnosed with SSNHL in our clinic from 2017 to 2024. This study reviewed the demographics, biochemical parameters (triglyceride and glucose), and hearing functions (pure tone audiogram data at diagnosis and month-3 follow-up) of patients. The inclusion criteria of the study were as follows: age \u0026gt;18 years, history of sudden HL, presence of routine biochemical test results, including fasting triglyceride (TG) and fasting plasma glucose (FPG), and audiological test results as well as comprehensive otolaryngological examination. We excluded patients with a history of another ear disease, those diagnosed with otosclerosis or Meniere\u0026rsquo;s disease, and those with tympanic membrane or external auditory canal pathology in otoscopic examination, are excluded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMeasurement of the TyG Index\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe TyG index was calculated using the following formula:\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTyG index = In [TG (mg/dL) \u0026times; FPG (mg/dL) / 2]\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTG and FPG levels were measured using automatic biochemistry analyzers and the enzymatic analysis method. The TG concentration was measured using the Roche Modular P and Roche Cobas 6000 chemistry analyzers. The FPG concentration was measured using a chemistry analyzer (Roche/Hitas Cobas C 501) that operated using the hexokinase-mediated reaction method.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAudiological Evaluation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAudiology tests are conducted in sound-insulated rooms. Otoscopic examination and tympanometry rule out pathologies of the outer and middle ear in all patients. Pure-tone audiometry tests were performed using an Interacoustics brand AC40 audiometry device, TDH-39 model supra-aural headphones that are integrated to the audiometry device, and bone vibrator in cabinets that meet standards of acoustic measurements. The air-conduction hearing threshold is 250-8000 Hz and bone conduction hearing threshold is 500-4000 Hz in both ears. The mean air and bone conduction pure sound frequencies were calculated using arithmetic averages of hearing thresholds at frequencies of 500, 1000, and 2000 Hz. Hearing loss examination is based on the Clark classification. The modified Siegeal criteria were used to evaluate hearing level during the follow-up and control periods (Table I). The MAICO MI 44 Analyzer (MAICO Diagnostic GmbH, Salzufer 13/14, D-10587 Berlin, Germany) was used for tympanometric examination. A stimulus (frequency = 226 Hz and SPL = 85 dB) was sent during the examination. Tympanogram curves were obtained using a probe inserted into the external acoustic canal by changing the air pressure from +200 daPa to -400 daPa.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eTable I.\u0026nbsp;\u003c/strong\u003eExamination of hearing level according to the Modified Siegel criteria before and after treatment\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 558px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eExamination of hearing level according to Modified Siegel criteria before and after treatment\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eGrading by mean pure tone threshold before treatment\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eGrade 1 Mean Hearing Thresholds \u0026le;25 dB HL\u003c/p\u003e\n \u003cp\u003eGrade 2 Mean Hearing Thresholds 26-40 dB HL\u003c/p\u003e\n \u003cp\u003eGrade 3 Mean Hearing Thresholds 46-75 dB HL\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Grade 4 Mean Hearing Thresholds 76-90 dB HL\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Grade 5 Mean Hearing Thresholds \u0026gt;90 dB HL,\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eExamination by mean pure tone threshold after treatment\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e(1) Complete Recovery \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Final Hearing Level \u0026le;25 dB HL\u003c/p\u003e\n \u003cp\u003e(2) Partial Recovery \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Hearing gain \u0026gt;15 dB and final hearing level 26-45 dB\u003c/p\u003e\n \u003cp\u003e(3) Mild Recovery \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; hearing gain \u0026gt;15 dB and final hearing level 46-75 dB\u003c/p\u003e\n \u003cp\u003e(4) No Recovery \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;hearing gain \u0026lt;15 dB and final hearing level 76-90 dB\u003c/p\u003e\n \u003cp\u003e(5) Total hearing loss \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Final Hearing Level\u0026gt;90 dB\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eConsidering 396 cases who are enrolled to the study, 50% of patients (n= 198) represented the control group and other 50% (n= 198) created the SSNHL group. There was no statistically significant difference between two groups in terms of distribution of sex (p= 0.382). Distribution of sexes in groups is homogeneous.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eParticipants of the SSNHL group were older than the patients of the control group and a significant difference is found (p= 0.013). Glucose level is significantly higher in the SSNHL group and a significant difference is observed (p=\u0026lt;0.001). There was no significant difference in TG levels between the groups (p = 0.301), but the TyG index was significantly higher in the SSNHL group than in the SSNHL group (p=\u0026lt;0.001). This result demonstrates that the TyG index is higher in the SSNHL group and that the TyG index correlates with the SSNHL (Table II).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable II.\u0026nbsp;\u003c/strong\u003eComparison of the control and sudden hearing loss groups in terms of demographics and metabolic parameters\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSudden hearing loss group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex, n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMale\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e99(50.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e103(52.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.382\u003csup\u003e*\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFemale\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e99(50.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95(48.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e49.26\u003c/strong\u003e\u003cstrong\u003e\u0026plusmn;14.76\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e53.64\u0026plusmn;15.40\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.013\u003csup\u003e\u0026amp;\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGlucose\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e98.58\u0026plusmn;23.72\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e116.07\u0026plusmn;54.59\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u0026lt;0.001\u003csup\u003e\u0026amp;\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTriglyceride\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e125.99\u0026plusmn;65.98\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e175.71\u0026plusmn;134.70\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.301\u003csup\u003e\u0026amp;\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTyG Index\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e8.58\u0026plusmn;0.59\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e8.92\u0026plusmn;0.84\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u0026lt;0.001\u003csup\u003e\u0026amp;\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" style=\"width: 604px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003csup\u003e*\u003c/sup\u003e\u003c/strong\u003e\u003cstrong\u003e: Chi-Square test,\u003csup\u003e\u0026amp;\u003c/sup\u003e: Mann\u0026ndash;Whitney U test\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003ePatients were assigned to study groups according to the level of HL before and after treatment; Table III shows the comparative results of the descriptive statistics of the TyG index levels. Statistically significant differences in the TyG index were found between patients assigned to study groups according to the level of HL before treatment; an obvious increase is observed particularly in patients with advanced stage disease (p\u0026lt;0.001). This result suggests that the TyG index is related to the severity of the disease. Significant differences were found between the study groups by recovery level after treatment in terms of the TyG index, and the differences between the group with full recovery and other groups demonstrate that the index can be related to the clinical process and it may reflect the metabolic changes in early grade (p\u0026lt;0.001).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable III.\u0026nbsp;\u003c/strong\u003eDescriptive statistics of the triglyceride\u0026ndash;glucose index levels in patients assigned to study groups according to the level of hearing loss before and after treatment and results of multiple comparisons\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLevel of hearing loss before treatment\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTyG\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRecovery level according to the mean result of pure tone audiometry after treatment\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTyG\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGrade 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e8.61\u0026plusmn;0.92\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e8.57(5.81-11.57)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e8.60\u0026plusmn;0.78\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e8.57(5.81-11.57)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGrade 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e8.82\u0026plusmn;0.68\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e8.79(7.58-11.27)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e9.11\u0026plusmn;0.76\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e9.02(7.72-10.91)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGrade 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e8.96\u0026plusmn;0.89\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e8.78(7.62-11.04)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e9.01\u0026plusmn;0.87\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e8.85(7.58-11.04)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGrade 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e9.04\u0026plusmn;0.87\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e8.97(7.85-11.63)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e9.34\u0026plusmn;0.82\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e9.30(7.96-11.63)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGrade 5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e9.56\u0026plusmn;0.68\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e9.66(8.05-11.04)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e9.35\u0026plusmn;0.87\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e9.52(7.62-11.04)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e\u0026amp;\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e\u0026amp;\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-2\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.127\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-2\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-3\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.104\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-3\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.028\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-4\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.074\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-4\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e1-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e2-3\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.580\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e2-3\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.539\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e2-4\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.357\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e2-4\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.294\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e2-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e2-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.257\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e3-4\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.679\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e3-4\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.202\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e3-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cem\u003e0.003\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e3-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.193\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e4-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.013\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003csup\u003e4-5\u003c/sup\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.748\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e\u003csup\u003e\u0026amp;\u003c/sup\u003e\u003c/strong\u003e\u003cstrong\u003e: Kruskal\u0026ndash;Wallis test, p\u003csup\u003e1-2\u003c/sup\u003e, p\u003csup\u003e1-3\u003c/sup\u003e, p\u003csup\u003e1-4\u003c/sup\u003e, p\u003csup\u003e1-5\u003c/sup\u003e, p\u003csup\u003e2-3\u003c/sup\u003e, p\u003csup\u003e2-4\u003c/sup\u003e, p\u003csup\u003e2-5\u003c/sup\u003e, p\u003csup\u003e3-4\u003c/sup\u003e, p\u003csup\u003e3-5\u003c/sup\u003e, p\u003csup\u003e4-5\u003c/sup\u003e: Mann\u0026ndash;Whitney U test is used for paired comparisons, while Bonferroni correction is performed to minimize the risk of type I error in multiple comparisons. In this context, the level of significance was set at 0.05/10 = 0.005.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe present study investigates the potential association between the TyG index and a series of audiometric and acoustic metrics. Spearman correlation analysis revealed significant positive relationships between the TyG index and multiple acoustic parameters (p\u0026lt;0.05). The mean air conduction values in the right and left ears were significantly correlated with the TyG index before and after treatment. Correlations between mean air conduction values of right and left ears, particularly before treatment, are intermediate, the effect of metabolic dysfunction on peripheral acoustic responses. This reveals that the TyG index-related acoustic changes are particularly remarkable at high frequencies (rho=0.25\u0026ndash;0.33, p\u0026lt;0.001). These results demonstrate that the TyG index is not only a marker of the systemic metabolic condition but may also have significant effects on the hearing system\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn the logistic regression analysis that is performed to determine the variables that can be related to sudden sensorineural hearing loss, univariate analyses are primarily performed and next, logistic regression analysis is performed, where the TyG index is added to the multivariate model, in addition to age and sex variables (Table IV). These results demonstrate that each increment in the TyG index increased the odds of SHL by approximately 0.5-fold. When age and sex variables were included in the multivariate analysis, sex and age did not have an independent effect, but the positive correlation of the TyG index with the SSNHL was still significant (Figure I).\u003c/p\u003e\n\u003cp\u003eThese results reveal that the TyG index can be a significant risk marker in the development of SSNHL independent of age and sex. Excluding the effects of age and sex supports the quality of the TyG index as an independent predictor. The relationship of the TyG index with insulin resistance and microvascular effects amplify the association of this biomarker with sudden vascular events, such as SHL.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable IV.\u0026nbsp;\u003c/strong\u003eResults of univariate and multivariate logistic regression analysis of variables related to sudden hearing loss.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUnivariate OR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMultivariate OR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003ep\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex, (Male)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e1.08(0.73-1.60)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.688\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.93(0.63-1.40)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.711\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge, (years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.98(0.97-0.99)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.005\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.99(0.98-1.06)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.234\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTyG Index\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.51(0.38-0.69)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.55(0.39-0.75)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations: OR = Odds Ratio; CI = Confidence Interval\u003c/p\u003e\n\u003cp\u003eROC analysis was performed to evaluate the power of the TyG index, which was included in the model because of the logistic regression analysis and significantly contributed to the prediction of SSNHL. According to the analysis results, the TyG index has low distinctiveness to predict SHL. The AUC (Area Under the Curve) that is calculated for the TyG index is 0.619 (95% CI: 0.564\u0026ndash;0.674), and this figure is statistically significant (p\u0026lt;0.001). The ROC curve in Figure II shows that the TyG index has low power to distinctly identify or predict patients with and without SSNHL. The maximum optimal cutoff value determined according to the Kolmogorov-Smirnov statistics is 8.63. Sensitivity (62.3%) and specificity (57.1%) are limited in this threshold value. The Gini index that reflects the classification success of the model is 0.148, and the model\u0026rsquo;s general quality is 0.51. This value shows that the model performs slightly better than random estimation.\u003c/p\u003e\n\u003cp\u003eThe evaluation of hearing levels before and after treatment according to the Modified Siegel criteria is presented in Table V. When the relation between hearing scores according to mean value of pure tone audiometry before treatment and hearing scores after treatment is reviewed, a statistically significant difference is not found (p \u0026lt;0.001). The linear-by-linear association test also confirmed this linear relationship (test statistic = 86.210; p \u0026lt; 0.001). These findings indicate that disease severity at the time of diagnosis is a significant determinant of response to treatment.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable V.\u0026nbsp;\u003c/strong\u003eEvaluation of hearing levels before and after treatment according to the Modified Siegel criteria\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003eGroups by the mean pure tone threshold before treatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eClinical examination by mean pure tone threshold after treatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003en (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 41px;\"\u003e\n \u003cp\u003eGrade 1 (n = 35, 17.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eComplete recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e30(85.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003ePartial recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e3(8.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eNo recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e2(5.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 41px;\"\u003e\n \u003cp\u003eGrade 2 (n = 64, 32.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eComplete recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e32(50.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003ePartial recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e24(37.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eMild recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e8(12.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" style=\"width: 41px;\"\u003e\n \u003cp\u003eGrade 3 (n = 58, 29.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eComplete recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e13(22.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003ePartial recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e18(31.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eMild recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e21(36.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eNo recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e2(3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eTotal hearing loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e4(6.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" style=\"width: 41px;\"\u003e\n \u003cp\u003eGrade 4 (n = 19, 9.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eComplete recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e5(26.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003ePartial recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e2(10.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eMild recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e4(21.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eNo recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e8(42.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" style=\"width: 41px;\"\u003e\n \u003cp\u003eGrade 5 (n = 22, 11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003ePartial recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e2(9.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eMild recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e4(18.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eNo recovery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e5(22.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003eTotal hearing loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e11(50.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 50px;\"\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026lt;0.001\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e*: Fisher-Freeman-Halton exact test.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStatistical analyses were performed using R (version 4.4.1, R Foundation for Statistical Computing) and \u003cem\u003eJASP\u003c/em\u003e (version 0.19.0, University of Amsterdam, Netherlands) software. The Kolmogorov\u0026ndash;Smirnov and Shapiro\u0026ndash;Wilk tests were employed to analyze the continuous variable\u0026rsquo;s distribution characteristics. The descriptive statistics of the variables are expressed as mean \u0026plusmn; standard deviation, median (minimum \u0026ndash; maximum), and frequency (n, %). Paired comparisons are analyzed with the Mann\u0026ndash;Whitney U test if the normality assumption is not ensured. When three or more groups are compared, ANOVA and Kruskal\u0026ndash;Wallis tests are used. Paired comparisons were performed using the Mann\u0026ndash;Whitney U test and Bonferroni correction is applied to compare the groups with significant differences as a result of the Kruskal\u0026ndash;Wallis test. In this context, the significance level was set at 0.05/10 = 0.005. For the comparison of categorical variables, the chi-square test and Fisher Freeman-Halton Exact tests are used by considering cross tabulation and expected cell frequencies.\u003c/p\u003e\n\u003cp\u003eLogistic regression analysis was performed to determine the factors that are effective in the development of SSNHL. The relationship between the TyG index and acoustic parameters are examined with the Spearman correlation analysis. Receiver operating characteristic (ROC) curve analysis was performed to determine whether the TyG index, which had a significant effect on the risk of SSNHL in the logistic regression analysis, has a diagnostic value to predict the presence of SSNHL. Statistical significance level is p\u0026lt;0.05 in all analyses.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe TyG index is a practical parameter that can detect metabolic signals, which indicate insulin resistance, without requiring complex laboratory tests, only because it can be calculated with FPG and TG levels.\u0026nbsp;In this aspect, it is a potential biomarker that can contribute to the prediction of early metabolic dysfunctions for large-scale population screenings and in clinical settings with limited resources [16].\u0026nbsp;According to the results of the multivariate logistic regression analysis performed in this study, the TyG index is an independent risk factor for SHL. This finding demonstrates that the TyG index plays a role in pathophysiology of the SHL as an indicator of metabolic dysfunction. The association between the TyG index and both insulin resistance and microvascular impairment supports its role in cochlear vascular insufficiency-mediated HL. However, because the AUC value is limited to 0.619, according to the ROC analysis result, the TyG index does not have sufficient performance as a diagnostic tool alone. The shape of the receiver operating characteristic (ROC) curve and its proximity to the diagonal reference line demonstrate that the index makes a limited contribution in terms of sensitivity and specificity. However, the limited diagnostic power observed in the ROC analysis should not overshadow the significance in the regression analysis because the TyG index can be a biomarker that reflects metabolic disorders, which pave the way for development of the disease, rather than diagnosis. In this context, the predictive role of the TyG index should not be ignored, and the potential of the index in multivariate models, where other variables of this parameters are used, should be more comprehensively investigated in advanced studies. Lisowska et al. reported that changes in cochlear micro-mechanics and retrocochlear auditory pathways manifest as subclinical hearing disorder in patients with diabetes mellitus [17]. In vitro studies revealed that glucose is used intensely in the development of the cochlea and that inner and outer hair cells are sensitive to oxygen and glucose deficiencies [18, 19]. Amarjargal et al. reported that the loss of hair cells occurs under conditions of glucose deficiency, and inner hair cells are \u0026nbsp;more sensitive than outer hair cells [19]. These findings are also supported by epidemiological evidences obtained by the American National Health Research, which revealed that adults with diabetes mellitus (21.3%) have more HL than those without (9.4%) [20]. In a 30-year epidemiological study conducted in Japan, the SHL tendencies were evaluated, and it was clarified that the number of patients with sensorineural hearing loss increased from 4000 in 1972 to 35000 in 2001, an increment of more than eight folds. One of the outstanding findings of this study is the recent significant increase in the prevalence of diabetes mellitus in patients with the SHL in comparison with date of the initial period [21]. Results of experimental studies reveal that hyperlipidemia (HL) has a significant effect on auditory functions [22, 23]. Experimental chronic hypercholesterolemia leads to accumulation of glucose in the cochlea by causing metabolic stress in the inner ear tissue, resulting in stria vascularis and edema in the outer hair cells [22]. These changes occur principally in the basal cochlear turn and are related to the loss of hearing sensitivity found in the auditory brainstem response (ABR) secondary to cholesterol-rich diet. In a case \u0026ndash; control study that examined the results of audiometry, ABR, and transient evoked oto-acoustic emission (TEOAE) in patients with hypercholesterolemia and hypertrygliceridemia, a significant difference was not found in mean hearing thresholds of the study and the control groups [5]. The literature had comprehensively addressed the role of lipids in pathogenesis of the sensorineural hearing loss (SNHL). The cochlea is an end organ that needs continuous nutrient and oxygen flow to continue its physiological functions, and it is substantially sensitive to circulatory changes [24]. High blood viscosity can decrease the blood supply to the inner ear, potentially resulting in injury to the inner ear [25]. Hyperlipidemia is a common condition in patients with SSNHL [8, 26]. Dietary approach and lipid-lowering treatment can be related to HL recovery [27]. Recent studies have revealed that inflammatory diseases, such as diabetes mellitus and cardiovascular disease, are proven risk factors for hyperlipidemia [28]. Moreover, various components of the metabolic syndrome, including high blood pressure and dyslipidemia, have relations with the HL [29]. Although there is sufficient principal research evidence to prove these risk factors of the pathogenic process, biomarkers with better correlation are still required for the SNHL.\u0026nbsp;In a national-scale study conducted by Liu et al. based on the NHANEs data, the prevalence of HL is higher in people with higher TyG index and that this relation is significant, particularly at high frequencies, and this index can be an independent risk factor for the SNHL\u0026nbsp;(OR = 1.12, 95% GA: 1.03\u0026ndash;1.22) [15]. Pan et al. determined determined a relation with the \u0026ldquo;U\u0026rdquo; configuration between the TyG index, speaking and hearing thresholds with high frequency and they found that this relation reverses above certain hearing thresholds and impairs the hearing function [30]. Wang et al. conducted a cross-sectional and Mendelian randomized study and demonstrated that the risk of SSNHL increases significantly in people with TyG index above 9.07 (HR: 3.60, 95% GA: 1.42\u0026ndash;9.14) and that genetically determined high triglyceride levels correlate with the increased risk of sensorineural hearing loss [31].\u0026nbsp;In addition, Amaral et al. found changes in systemic inflammation markers, such as adiponectin,\u0026nbsp;TNF-\u0026alpha; and IFN-\u0026gamma;, in patients with SSNHL and suggested that these changes can be related to hearing recovery [32].\u0026nbsp;This finding demonstrates that metabolic and inflammatory processes play a joint role in the pathophysiology of HL. In experimental studies that are conducted on animal models, electrophysiological dysfunction and a significant increase in oxidative stress markers were observed in the auditory tracts of rats that are exposed to hyperglycemia [33]. This also supports the idea that glucose fluctuations may lead to cochlear injury even in the prediabetic period. The TyG index is also related to cognitive dysfunctions and dementia. This condition suggests that systemic microvascular dysfunctions may be effective not only at the cerebral level but also at the cochlear level [9]. On the other hand, the effect of the components of the metabolic syndrome, such as diabetes mellitus and insulin, on hearing health is strongly supported in the literature. Bainbridge et al. reported that HL in both low and high frequencies is significantly more common in people with diabetes mellitus [20]. Experimental studies have reported histopathological changes in the inner ear, particularly outer hair cells, secondary to dyslipidemia [22, 29]. Kojima et al. reported significant hearing recovery in patients with late-stage SSNHL after treatment of the HL. Circulatory recovery may support hearing function [27]. Kaneva et al. emphasized that the atherogenic index can be used as a predictive biomarker for SSNHL and that a high atherogenic load can increase the risk even if conventional lipid parameters are normal [8]. Lee et al. reported that high total cholesterol and triglyceride levels as wandsity increase the incidence of SSNHL, and the treatment response is poorer in these individuals than in those without [25]. Finally, although the current guidelines express that SSNHL is mostly idiopathic, they also highlight the need to investigate the underlying vascular factors [28]. Subclinical auditory changes secondary to insulin resistance are at detectable level in otoacoustic emission and auditory brain stem potentials, and these findings are significant in terms of the importance of regulating blood glucose at the cochlear level [17]. It has been reported that auditory conduction slows down significantly in both peripheral and central nervous pathways in patients with type I and type II diabetes mellitus [34]. Vascular and thrombophilic risk factors are also important in development of the SSNHL. Marcucci et al. determined that anticardiolipin antibodies and elevated PAI-1 and homocysteine levels are significantly associated with SSNHL, which can trigger microcirculatory dysfunction and coagulopathy [4]. Hearing loss is also induced in a cochlear ischemia\u0026ndash;reperfusion model in experimental animal studies, and antioxidative agents reduce the injury [24]. Perez et al. reported apparent vestibular and cochlear dysfunctions and higher latency and lower amplitude in vestibular evoked potentials in animal models of type 2 diabetes; these findings demonstrate the direct neurotoxic effects of glycemic dysregulation on the inner ear [7]. Qatar et al. conducted an experimental study on rats exposed to hypertriglyceridemia and found stria vascularis, obvious edema in hair cells, cellular degeneration, and increased hearing threshold [23]. Microcirculatory dysfunction secondary to dyslipidemia can lead to CI. Teranishi et al. conducted a 30-year epidemiological study in Japan and reported that the incidence of SHL is increasing, and the increment is more remarkable in people with hypertension and diabetes mellitus [21]. These data strengthen the role of metabolic diseases in etiopathogenesis of the SSNHL. Our results support the idea that the TyG index is an independent risk factor for SSNHL and has the potential to be a metabolic biomarker. However, limited diagnostic accuracy\u0026mdash;a finding that has also been observed in previous trials\u0026mdash;makes it difficult to use this index alone as a sufficient marker [35]. Studies conducted by Deng et al. and based on Mendel randomization analysis with two samples demonstrated that elevated TG can play a causative role in SSNHL, and the authors have emphasized that TG metabolism should be closely monitored and regulated, if required [36]. The TyG index and its derivatives (TyG-BMI, TyG-WC, and TyG-WHtR) have gained importance as practical and cost-effective biomarkers that can be used to examine insulin resistance in large populations. Nonlinear curves, particularly with the \u0026ldquo;U\u0026rdquo; configuration, have identified significant relationships between the risk and severity of coronary artery disease in patients with type II DM and H-type hypertension [37, 38]. The TyG index offers a clinical advantage because of its high applicability and lack of requirement for measuring insulin levels. It can be considered a potential risk market in diseases, such as SSNHL, where vascular and metabolic mechanisms are effective [16, 39].\u003c/p\u003e\n\u003cp\u003eThe higher TyG index score in our patients with sudden hearing loss than in the control group suggests that insulin resistance and resultant metabolic disorders may play a role in the disease etiology. A large-scale study on patients with hypertension demonstrated that the TyG index is an independent predictor for all-cause mortality [12]. Similarly, high TyG index can be related to HL secondary to vascular dysfunction and metabolic stress in conditions where microvascular susceptibility, such as the SSNHL, plays a role. Hence, Wang et al. conducted a large-scale study on the Chinese population and reported that the TyG index alone is not significantly related to HL, but BMI, particularly the TYG-BMI index, is strongly correlated with HL in elderly people [40]. Kim et al. reported that the TyG index has a statistically significant correlation with high-frequency HL in middle-aged Korean women. These results support the idea that cochlear microvascular dysfunction secondary to insulin resistance may play a role in the pathophysiology of HL [41].\u003c/p\u003e\n\u003cp\u003eIn this context, we aimed to show that the TyG index, an indicator of the insulin resistance, can be related to disease prognosis and may have a prognostic value. Our results reveal that treatment response is closely related to the disease presentation grade in patients with SSNHL. Patients with low grade have better treatment response, whereas those with high grade have a higher rate of irresponsiveness. In this context, early diagnosis and quick disease treatment can increase the success of treatment. Our results are consistent with the literature that supports the role of the initial hearing level in SSNHL prognosis. Moreover, significant results in the linear-by-linear association analysis show a linear relationship between grade and treatment response, which can be considered in prognostic classification.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe outcomes of this study show that the TyG index is a unique metabolic risk marker for SSNHL. This parameter that reflects the insulin resistance and microvascular function can point to the systemic processes that play a role in the pathophysiology of the HL. Despite the limited diagnostic accuracy in the ROC analysis, the significant results obtained in the multivariate analysis support the predictive value of the TyG index (). The use of this index, along with other metabolic markers in the clinical evaluation process, may contribute to the identification of high-risk individuals. The strong correlation between disease presentation grade and response to treatment emphasizes the importance of early diagnosis and treatment in terms of prognosis. In this context, the combined evaluation of the TyG index and clinical grading can enable the development of a more personalized approach for the management of SSNHL.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Limitations","content":"\u003cp\u003eThe retrospective and single-center design of the study limits the ability to identify a causative relationship and generalize the findings. Potential confounding variables, such as diet, physical activity, and comorbidities, were not considered in the evaluation of the TyG index examination. Time-dependent changes in the index were not analyzed. Prospective, multicenter studies addressing longitudinal biomarker analyses are required.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003e\u003cem\u003eConflict of Interest\u003c/em\u003e\u003c/strong\u003e\u003cem\u003e:\u003c/em\u003e The authors have no relevant financial or non-financial interests to disclose\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eEthics Committee Approval:\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eThis study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Sivas Cumhuriyet University (Date: January 16, 2025/ No. 2025-01/164).\u0026nbsp;Written informed consent requirement was waived due to the retrospective design.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u003c/strong\u003e Not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHuman Ethics and Consent to Participate declarations:\u003c/strong\u003e Not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e The authors received no financial support for the research, authorship, and/or publication of this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConceptualization:\u0026nbsp;Ahmet Aksoy; Tuba Doğan Karataş\u0026nbsp;Methodology: Tuba doğan Karataş, Ahmet Aksoy;\u0026nbsp;Formal analysis and investigation: Ahmet Aksoy;\u0026nbsp;; Writing - original draft preparation: Ahmet Aksoy;\u0026nbsp;Writing - review and editing:\u0026nbsp;Ahmet Aksoy; Tuba Doğan Karataş\u0026nbsp;Funding acquisition: Ahmet Aksoy;\u0026nbsp;Resources:\u0026nbsp;Ahmet Aksoy, Tuba Doğan Karataş;\u0026nbsp;Supervision:\u0026nbsp;Ahmet Aksoy, Tuba Doğan Karataş\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments:\u0026nbsp;\u003c/strong\u003eThe study was presented orally at the 29th International Rhinocamp Meeting, held from May 22 to 25, 2025, in Marmaris, Muğla, Turkey.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003e\u003cstrong\u003eAksoy A, \u0026Ouml;zata G\u0026uuml;ng\u0026ouml;r \u0026Ouml;. 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Correlation between hearing impairment and the triglyceride-glucose index in middle-aged female based on a Korean National Health and Nutrition Examination Survey.\u003c/strong\u003e Medicina. 2024; 60(10):1596. doi:10.3390/medicina60101596\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bratislava-medical-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Bratislava Medical Journal](https://link.springer.com/journal/44411)","snPcode":"44411","submissionUrl":"https://submission.springernature.com/new-submission/44411/3","title":"Bratislava Medical Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Triglyceride–Glucose Index, Sudden Hearing Loss, Biomarker, Otological emergency","lastPublishedDoi":"10.21203/rs.3.rs-8013375/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8013375/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e\u003cp\u003eThis study aimed to retrospectively evaluate triglyceride-glucose (TyG) index levels in patients with sudden sensorineural hearing loss (SSNHL) and explore its potential as a biomarker for early diagnosis or risk prediction.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003e This retrospective study included patients aged 18 years who were diagnosed with SSNHL from 2017 to 2024 following institutional ethics approval (2025-01/164). Complete fasting triglyceride (TG), fasting plasma glucose (FPG), and audiometric data (baseline and 3-month pure tone averages) were required for eligibility. Patients with a history of chronic otitis media, otosclerosis, meniere\u0026rsquo;s disease, or prior ear surgery were excluded from the study. Hearing thresholds of 500, 1000, 2000, and 4000 Hz were evaluated using the modified Siegel criteria. Statistical analyses were performed using R (version 4.4.1) and JASP (version 0.19.0), with p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 considered statistically significant.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eA total of 396 patients were included, with 50% serving as the control group. No significant differences in age, sex, glucose, or TG levels were observed between the groups. However, the SSNHL group had significantly higher TyG index values (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The TyG index was strongly associated with the severity and recovery of hearing loss, as determined by the modified Siegel criteria (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and was positively correlated with hearing thresholds across frequencies. TyG was identified as an independent risk factor for SSNHL (Odds ratio\u0026thinsp;=\u0026thinsp;0.55; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). However, the ROC analysis revealed limited discriminatory capacity (AUC\u0026thinsp;=\u0026thinsp;0.619), indicating that TyG may not be a sufficient standalone diagnostic marker.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eThis study is among the first to analyze the relationship between SSHL and the TyG index. The TyG index was identified as an independent risk factor for SSNHL and may serve as a potential predictive biomarker, particularly within multivariate models.\u003c/p\u003e","manuscriptTitle":"Evaluating the Role of Triglyceride–Glucose Index in Sudden Hearing Loss","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-12 13:22:15","doi":"10.21203/rs.3.rs-8013375/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-01-29T15:55:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"88859647466718676797397544220317137302","date":"2026-01-12T20:27:01+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-12-08T22:18:20+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-11-04T10:21:01+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-11-04T10:16:41+00:00","index":"","fulltext":""},{"type":"submitted","content":"Bratislava Medical Journal","date":"2025-11-02T22:28:09+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bratislava-medical-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Bratislava Medical Journal](https://link.springer.com/journal/44411)","snPcode":"44411","submissionUrl":"https://submission.springernature.com/new-submission/44411/3","title":"Bratislava Medical Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"faf25779-5569-4a64-807e-e604f451d899","owner":[],"postedDate":"December 12th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-02-13T16:55:39+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-12 13:22:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8013375","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8013375","identity":"rs-8013375","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}