The Prevalence of Hearing Loss Among Patients With Hypothyroidism at Kenyatta National Hospital

Abstract

Background: The association between hypothyroidism and hearing loss has been well documented. The prevalence of hearing loss in acquired hypothyroidism is 25% and in congenital hypothyroidism it is 35-50%. However, there is paucity of local data on this subject. Study objective: To determine the prevalence, types, and degree of hearing loss among patients with hypothyroidism at Kenyatta National Hospital Study setting: The study was carried out at the Kenyatta National Hospital endocrine, surgical thyroid, and Ear, Nose and Throat clinics. Study duration: This study took twelve months Study design: This was a cross-sectional study Study population: A total of 79 patients (18 to 60 years) diagnosed with hypothyroidism by an endocrinologist were recruited. Methodology: Biochemically hypothyroid individuals had their medical history taken and were physically examined. Hearing was assessed with pure tone audiometry at frequencies of 250 Hz to 8000 Hz. Data collection and analysis: Data was captured and analyzed by the Statistical Package for Social Sciences (SPSS Version 22.0). Continuous variables were compared using the Student’s t-test while Chi-square test was used to analyze categorical variables. A 95% confidence interval was used and a p value of 0.05 considered statistically significant. Results: There was a prevalence of hearing loss of 9.5% with a statistically significantly high proportion affected at 8000 Hz (p < 0.05). Sensorineural hearing loss was noted in 13 ears (86.7%) and mixed hearing loss in 2 ears (13.3%). The degree of hearing loss was predominantly mild and was present in 13 ears (86.7%). Hearing thresholds correlated positively with thyroid stimulating hormone levels, but this was not statistically significant (p > 0.05). Conclusion and Recommendations: There was a 9.5% prevalence of hearing loss among the hypothyroid patients with a predominance of sensorineural type and mild degree of hearing loss. The correlation of thyroid stimulating hormone and hearing thresholds was weakly positive. Routine hearing screening of hypothyroid patients above 50 years is recommended