Elevated Triglyceride Glucose Index is Associated with Poor Hearing Recovery in Sudden Sensorineural Hearing Loss

Importance: Cochlea microcirculation dysfunction has been proposed as a vital etiology for sudden sensorineural hearing loss (SSNHL), wherein insulin resistance acted as a potential risk factor for microcirculatory dysfunctions. The triglyceride glucose (TyG) index, a validated surrogate of insulin resistance, has not been fully evaluated in SSNHL. Objective: To evaluate the association between the TyG index and hearing recovery in patients with SSNHL. Design: Retrospective cross-sectional study involving a large, clinically characterized cohort. Setting: Tertiary university hospital. Participants: A total of 944 adult SSNHL patients were included between January 2018 and March 2024. Eligibility required onset within 14 days and completion of standardized treatment and follow-up audiometry. Patients with conductive, recurrent, or secondary causes of hearing loss were excluded. Exposures: The TyG index was calculated as ln [fasting plasma glucose (mg/dL) × triglycerides (mg/dL)/2]. Main Outcomes and Measures: Hearing recovery was assessed after 14 days of treatment using Siegel’s criteria and categorized as complete or incomplete recovery. Results: Among 944 patients (mean [SD] age, 49.3 [15.6] years; 458 men [48.5%]), 208 (22.0%) achieved complete recovery. Baseline hearing levels and audiogram pattern were similar across TyG tertiles. However, the proportion of patients achieving complete recovery was lower in the highest TyG tertile compared to the 2 lower tertiles (45 [14.3%] vs 77 [24.4%] vs 86 [27.4%]; P < .001, respectively). In fully adjusted logistic regression models, higher TyG index was independently associated with incomplete recovery with an odds ratio (95% CI) of 1.93 (1.14-3.29) in tertile 3 and 1.55 (1.05-2.29) for per unit increase in the TyG index. Conclusion: Higher TyG index values were independently associated with poorer hearing recovery in SSNHL. Relevance: The TyG index may help clinicians identify SSNHL patients at risk of poor cochlear recovery, supporting earlier and more targeted management.