OTOACOUSTIC EMISSION AND AUDITORY BRAINSTEM RESPONSE IN PATIENTS WITH AUTOIMMUNE THYROIDITIS

Area of Science:

• Oto-neurology
• Endocrinology
• Immunology

Background:

• Euthyroid autoimmune thyroiditis (AIT) is an endocrine disorder.
• Outer hair cell (OHC) function is crucial for hearing sensitivity.
• The impact of AIT on auditory function, especially OHCs, remains under-investigated in euthyroid patients.

Purpose of the Study:

• To investigate the function of OHCs in patients with euthyroid AIT.
• To assess the influence of AIT factors on auditory function in individuals without self-reported hearing loss.
• To determine the correlation between autoimmune markers and OHC function.

Main Methods:

• Study included 59 patients with euthyroid AIT and 29 healthy controls.
• Measured thyroid hormones (TSH, T4, T3) and antibodies (TPAb, TGAb).
• Assessed OHC function using distortion product otoacoustic emissions (DPOAE) and auditory brainstem response (ABR).

Main Results:

• A statistically significant correlation was found between increased autoimmune activity (TPAb, TGAb levels) and decreased OHC function.
• This decline in OHC function was most pronounced in the high-frequency range (5714 - 8000 Hz).
• No subjective hearing loss was reported by the patient group.

Conclusions:

• Euthyroid autoimmune thyroiditis can negatively impact outer hair cell function.
• Elevated autoimmune markers in AIT are associated with subclinical auditory dysfunction.
• High-frequency auditory assessment may be beneficial for early detection of hearing changes in AIT patients.