Effects of Type 2 Diabetes Mellitus on Auditory Function: A Literature Review

Abstract

Introduction: Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by hyperglycemia resulting from impaired insulin secretion or action. Chronic hyperglycemia can lead to microvascular and neuropathic complications, including those affecting the auditory system. This literature review aims to explore the mechanisms of auditory dysfunction caused by T2DM and to examine scientific evidence regarding the relationship between T2DM and auditory function impairment.

Method: This review employed a narrative approach by searching the PubMed, ScienceDirect, and Google Scholar databases using the keywords “type 2 diabetes mellitus,” “hearing loss,” and “auditory function.” Selected articles were publications from the last five years (2020–2025) relevant to the topic.

Discussion: T2DM can affect hearing through microvascular damage to cochlear capillaries, auditory nerve neuropathy, oxidative stress, and the accumulation of advanced glycation end products (AGEs). These mechanisms lead to stria vascularis dysfunction, cochlear hair cell atrophy, and impaired nerve impulse transmission. Several studies have reported an increased risk of bilateral sensorineural hearing loss among T2DM patients, particularly in those with poor glycemic control and longer disease duration.

Conclusion: T2DM is associated with auditory dysfunction through vascular, neuropathic, and oxidative mechanisms. Routine audiometric examinations are recommended for early detection of auditory impairment as part of comprehensive diabetes care.