The Relationship between Levels of Thyroid-stimulating Hormone and Free Thyroxine and Impaired Outer Hair Cell Function in Pediatric Hypothyroid Patients

A BSTRACT Introduction: Hypothyroidism causes damage to the sensory morphology of the outer hair cell (OHC) and reduced microtubules in the supporting cells that can affect cochlear maturation, causing hearing loss. This study aimed to explain the relationship between thyroid-stimulating hormone (TSH) and free thyroxine levels with impaired OHC function in pediatric hypothyroid patients. Methods: This study was an observational analytic study with a cross-sectional design. This study was conducted in the Endocrinology Division of the Pediatric Outpatient Clinic of Dr. Soetomo General Academic Hospital, Surabaya, Indonesia. Otoacoustic Emission (OAE) examination was carried out in the Neurotology Division of the otolaryngology-head and neck surgery (ORL-HNS), for 2 months from August to September 2024. The sample size was taken consecutively, and as many as 30 patients met the inclusion and exclusion criteria. Baseline data, including gender, age at diagnosis, diagnosis of hypothyroidism, and duration of hypothyroid therapy, were obtained from medical records. The study subjects were anamnesis and underwent basic physical examination of ORL-HNS, then underwent tympanometry and OAE examination. The statistical test in this study used the Kruskal–Wallis test with a significance level of 0.05. Results: The 30 pediatric hypothyroid patients who had met the inclusion and exclusion criteria. Analysis of the relationship between FT4 levels and OHC function disorders in OAE frequency 2000 Hz obtained P = 0.029 ( P > 0.05). The relationship between TSH levels and disorders at all OAE frequencies obtained ( P > 0.05). Conclusion: This study concludes a significant relationship between FT4 levels and OHC function disorders in OAE frequency 2000 Hz.