Association of thyroid dysfunction with occurrence and prognosis in moderate-to-severe sudden sensorineural hearing loss with adjunctive hyperbaric oxygen therapy: a retrospective clinical study

Objective: To investigate the relationship between thyroid dysfunction and both the occurrence and therapeutic prognosis of moderate-to-severe sudden sensorineural hearing loss (SSNHL) treated with hyperbaric oxygen therapy (HBOT) as an adjunctive treatment. Methods: : A retrospective analysis was conducted involving 250 patients with moderate-to-severe SSNHL and 250 matched healthy controls with available thyroid function profiles from January 2017 to December 2020. Logistic regression analysis was adopted to identify risk factors for the occurrence of moderate-to-severe SSNHL. Therapeutic efficacy was evaluated based on overall response rate, frequency-specific hearing improvement after HBOT combined therapy. Results: : The prevalence of thyroid dysfunction was significantly higher in patients with moderate-to-severe SSNHL than in controls (40.8% vs. 24.4%, P < 0.001), primarily characterized by a higher rate of thyroid autoantibody positivity (TPOAb, TgAb). Multivariate analysis identified decreased TT3 (OR = 0.055, 95% CI: 0.017-0.235, P < 0.001), decreased FT3 (OR = 0.077, 95% CI: 0.043-0.160, P < 0.001), and TPOAb positivity (OR = 3.102, 95% CI: 1.348-7.138, P = 0.008) as independent risk factors for moderate-to-severe SSNHL. The combination therapy including HBOT yielded an overall response rate of 64%. Furthermore, TPOAb-positive patients exhibited significantly poorer recovery at 1000 Hz and 2000 Hz compared to TPOAb-negative patients ( P < 0.05). Conclusions: : Thyroid dysfunction (low TT3, low FT3, and TPOAb positivity) is associated with an increased risk of moderate-to-severe SSNHL. TPOAb positivity impaired mid-frequency (1000Hz and 2000Hz) recovery, underscoring the significance of assessing thyroid function in the management and prognostic evaluation of moderate-to-severe SSNHL.