Evaluation of Hearing loss by Pure Tone Audiometry in Type 2 Diabetes Mellitus

Abstract

Introduction: The association of hearing loss and diabetes has been under research for many years. The hearing loss in diabetes in our population has not been studied extensively. The objective of this study was to compare the hearing threshold between type 2 diabetic patients and age- and sexmatched controls.
 Materials and Methods: A comparative study was done in the Department of ENT, Kathmandu Medical College from October 2019 to February 2020. The hearing threshold, of 40 type 2 diabetics patients, and 40 age- and sex-matched healthy controls in the age group of 35 to 55 years, were assessed by pure tone audiometry. The hearing threshold was compared between the two groups by using the student’s unpaired t-test.
 Results: Among 40 diabetes patients, 29 (72.5 %) had bilateral, mild to moderate sensorineural hearing loss. The hearing threshold in diabetes patients was signifi cantly higher than the healthy controls in all the frequencies except at 250 Hz. When comparing the threshold according to the duration of diabetes, it was found to be signifi cantly higher only at higher frequencies (4000 and 8000 Hz) in diabetes with more than 5 years duration.
 Conclusions: The hearing loss was common in type 2 diabetes mellitus. Most diabetic patients had mostly bilateral mild to moderate sensorineural hearing loss affecting hearing thresholds in higher frequencies than the healthy controls as assessed by pure tone audiometry.

Prevalence and Associated Factors of Sensorineural Hearing Impairment Among Patients with T2DM in Amhara Region, Northwest Ethiopia, 2022: A Multi-Centered Cross-Sectional Study

“… 47 The results of the current study suggested that individuals with a long duration of T2DM had a higher chance of developing SNHI than those with a short-term duration. This was in line with studies done in Mexico, 35 Indonesia, 48 Turkey, 49 Nepal, 1 Iran, 29 China, 37 Jammu, 46 India, 50 Saudi Arabia, 25 and South Africa. 26 The possible reason might be that chronic hyperglycemia affects the inner ear nerve tracts and blood vessels by increased reactive oxygen species.…”

“… 27 The consistency in study design and participant characteristics may account for the observed trend. However, the findings from this study revealed lower values compared to similar research conducted in Japan (60.2%), 28 Iran (85%), 29 Nepal (72.5%), 1 India (58%), 30 North India (81%), 31 and Nigeria (71.8%). 32 This possible discrepancy might be due to natural disasters such as volcanic eruptions, flooding, and tsunamis that regularly affect Asian countries.…”

“…Sensorineural hearing impairment: Was an average hearing threshold above 25 decibels at 0.5, 1, 2, 4 and 8 kHz. 1 , 2 …”

“…Sensorineural hearing impairment (SNHI) is a disability in which an individual is unable to hear sounds in one or both ears within 25 dB. 1 , 2 In recent times, SNHI resulting from prolonged exposure to diabetes mellitus has emerged as a significant global public health issue. 2 Type 2 diabetes mellitus (T2DM) leads to a gradual, bilateral, and permanent SNHI.…”

Prevalence of hearing impairment in patients with diabetes mellitus at tertiary care center of Nepal

“…This finding was less compared to earlier studies where the prevalence of hearing loss in diabetes mellitus patients quoted from a range of 33.7% to 97.6%. [15][16][17][18][19] We did not find clarification for such a broad variation, but it could be attributed to the study methodology of differences in inclusion criteria, demographics, type and duration of diabetes mellitus, the clinical and biochemical status of diabetes mellitus patients. The current study did not limit the recruitment of study participants according to the duration of disease, age, or gender.…”