Abstract
Background: Type 2 diabetes mellitus (T2DM) has been linked to many problems, including hearing loss, which research studies have not paid much attention to. This study looks into the possible links between hearing loss in people with T2DM, the duration of time they have had diabetes, how well they control their blood sugar, and measures of reactive stress. Understanding how these things work together can help doctors find problems faster, develop better ways to treat them, and improve their patients’ health.

Aims and Objectives: This study aims to see if there are any links between hearing loss and duration of T2DM, levels of glycemic control, and measures of oxidative stress in people with T2DM. The results of this study will help come up with early identification and healing ways to improve patient care.

Materials and Methods: In a cross-sectional study at Government Medical College, Kozhikode, 63 diabetic patients aged 30–60 were compared with 63 age and sex-matched controls. Blood sugar was assessed using the glucose oxidase peroxidase method, hemoglobin A1C (HbA1C) through cation exchange high-performance liquid chromatography, serum malondialdehyde (MDA) through the thiobarbituric acid test, and superoxide dismutase (SOD) using the technique by Marklund and Marklund, with the latter two assessed spectrophotometrically. Hearing abilities were evaluated using pure tone audiometry.

Results: Diabetic participants exhibited a marked increase in hearing loss incidence compared to controls (P < 0.001). Males with diabetes showed a higher prevalence of hearing loss than females (P = 0.043). A significant correlation was found between hearing loss and the duration of diabetes (P < 0.001), elevated glycemic levels (fasting blood sugar, random blood sugar, and HbA1c, all P < 0.001), and altered oxidative stress parameters. Specifically, MDA levels were higher in people with diabetes (P < 0.001) and associated with hearing loss (P = 0.033), while SOD levels were reduced (P < 0.001) and significantly linked to hearing loss (P = 0.047). Logistic regression identified age, sex, HbA1c, MDA, and SOD as independent risk factors for hearing impairment in Type 2 diabetes patients.

Conclusion: Our findings emphasize the significant association between Type 2 diabetes and heightened risk of hearing loss, influenced by age, gender, glycemic levels, and oxidative stress markers. Regular audiological assessments are crucial for early detection and intervention in diabetic patients.

Key words: Type 2 Diabetes Mellitus; Hearing Loss; Oxidative Stress; Malondialdehyde; Superoxide Dismutas; Audiological Assessments