Audiological evaluation (128-20.000 Hz) in women with autoinmune thyroiditis: The role of antibodies vs. l-thyroxine deficiency

Background and aim: Although sensorineural hearing loss may have different aetiologies, we focused on autoimmune hearing loss since it may be reversible with corticosteroid therapy; this entity is sometimes associated with systemic autoimmune diseases. Hashimoto's thyroiditis or chronic autoimmune thyroiditis shows antibodies and may be harmful to hearing thresholds regardless of hypothyroidism effect. To date this effect has not been sufficiently studied and never with extended high frequencies. The aim of this work is to study by age groups whether hearing thresholds in the human auditory range (128 to 20.000 Hz) are affected in Hashimoto's disease.Materials and methods: Two groups of 128 patients affected by Hashimoto's thyroiditis were included. First group: patients with pathological antithyroid antibodies who do not need L-thyroxine treatment. Second group: patients controlled with L-thyroxine substitutive treat-ment. Audiometric threshold study comparing between the groups of patients and a group of 209 controls was performed. All patients underwent complete otorhinolaryngological examination, antithyroid antibodies, TSH, T3 and T4 blood levels, tympanometry, conventional pure-tone audiometry, and extended-high-frequency audiometry.Results: All patients were women. Both groups showed worst audiometric thresholds than the control group; both study groups showed worse hearing than controls, this difference was sta-tistically significant in all frequencies. In the 8-20 kHz frequency range this difference was more than 10 dB, and in the 9-16 kHz and 20 kHz range this difference was more than 20 dB. When separated by age groups, in younger subjects (20-29 years) these differences were found in all frequencies, except for conversational frequencies (500 -4,000 Hz); between 30 and 49 years the difference is statistically significant in all frequencies; and from 50 to 69 years differences are found, especially in the conversational frequencies.Conclusions: This first work studying the human auditory range in the chronic autoimmune thyroiditis or Hashimoto's thyroiditis confirms that hearing loss related to the autoimmune disorder predominates at extended-high-frequencies initially. But ends up involving all frequen-cies in pure-tone conventional audiometry, then it may be detected in routine clinical tests. These results support the role of extended-high-frequencies audiometry to diagnose subclinical hearing loss in patients affected by Hashimoto's thyroiditis.(c) 2022 Sociedad Espan tilde ola de Otorrinolaringologi acute accent a y Cirugi acute accent a de Cabeza y Cuello. Published by Elsevier Espan tilde a, S.L.U. All rights reserved.