Assessment of audiologic evaluation in patients with acquired hypothyroidism

Introduction: Hypothyroidism is a common endocrine disorder resulting from deficiency of thyroid hormone or, more rarely, from their impaired activity at tissue level. In its clinically overt form, hypothyroidism is a relatively common condition, with an approximate prevalence of 2% in adult women and 0.2% in adult men. Deficiency of the hormone has a wide range of effects, because all metabolically active cells require thyroid hormone. Aim of the study: To determine the incidence of deafness in patients suffering from goiterous hypothyroidism exclusively and to evaluate the role of L-thyroxine therapy in improving the hearing in this group of patients. Materials and methods: Two groups were included: a hypothyroidism group (HG, n-30), and a control group (CG, n-30). Parameters studied: gender, time of hypothyroidism, co-morbidities, cochleovestibular symptoms, biochemistry and hormonal exams (TSH, T4), tonal audiometry, TOAEs and BERA. Results: All participants were women, 70% of the HG had Hashimoto thyroiditis, and 60% of the HG had had the diagnostic of the hypothyroidism for at least five years. Depression and hypertension were frequent in HG. All HG patients had altered TSH values and 50% had diminished T4 values. Sensorineural hearing loss was detected in 22 ears from the HG and in seven from the CG. BERA was normal in the CG and altered in 10 ears from the HG, showing L-V increase. TOAEs were absent in 12 ears from the HG and in four from the CG. Conclusions: HG patients had more cochleovestibular symptoms, higher audiometric thresholds, and increase in L-V in the BERA and absence or reduction in TOAEs amplitudes. Such alterations were not associated with THS and free T4 levels.