OTO Journal Studies: Link Between Type 2 Diabetes and Hearing Loss
Recent systematic reviews provide comprehensive evidence for screening and early intervention.
From the AAO-HNSF
Despite analyzing different study populations and using distinct methodologies, both investigations reached strikingly similar conclusions about the prevalence, severity, and characteristics of hearing loss in diabetic patients.
The Scope of the Problem
With diabetes affecting over 422 million people globally—a number that has nearly quadrupled since 1980—and hearing loss projected to affect 2.45 billion people by 2050, the intersection of these two conditions has become increasingly critical. Type 2 diabetes accounts for approximately 90% of all diabetes cases and is well-known for its microvascular complications including retinopathy, nephropathy, and neuropathy. However, the auditory system's vulnerability to diabetic pathophysiology has received less attention.
Complementary Evidence from Two Large Meta-Analyses
The study conducted by Kim et al. (2025) presented at the AAO-HNSF 2025 Annual Meeting & OTO EXPO, and published in the December 2025 issue, analyzed 39 studies encompassing 88,395 patients with T2DM and 20,337 controls. The research team found that patients with T2DM demonstrated a significantly higher prevalence of clinically significant hearing loss compared to controls (53.0% vs. 25.2%).
The second study, authored by Caballero-Borrego and Andujar-Lara (2025) from Barcelona, Spain, and published in the November issue, examined 17 studies with 3,910 diabetic patients and 4,084 controls. The analysis also reported a pronounced association: the prevalence of hearing loss among patients with type 2 diabetes ranges from 40.6% to 71.9%, and compared to the control group, the risk of hearing loss is 4.19 times higher in those with diabetes.
Characteristics of Diabetic Hearing Loss
Both studies provide detailed characterization of hearing loss in T2DM patients. Kim et al. found that sensorineural hearing loss was the predominant type (46.2%), followed by mixed (10.4%) and conductive (5.0%) hearing loss. Importantly, bilateral hearing loss (29.6%) was significantly more common than unilateral involvement (15.0%).
The severity distribution revealed that most patients experienced mild-to-moderate impairment. Using WHO criteria, Kim's analysis showed 22.1% with mild hearing loss (26-40 dB), 25.5% with moderate loss (41-60 dB), 8.5% with severe loss (61-80 dB), and 1.7% with profound loss (>80 dB)—all significantly higher than controls.
Caballero-Borrego's study demonstrated that mean pure-tone audiometry thresholds were 3.19 dB higher in diabetic patients overall, with this difference more pronounced at high frequencies (4000-8000 Hz) where diabetics showed a 2.3 dB elevation compared to only 1.11 dB at low frequencies (500-2000 Hz).
These two independent meta-analyses provide evidence that type 2 diabetes significantly increases the risk of hearing loss, with prevalence rates higher than in non-diabetic populations. As the authors note, incorporating hearing assessment and management as a part of routine diabetes care could represent an important opportunity for early intervention and improved patient outcomes.
References
Kim CH-s, Lauritsen KL, Nguyen SA, Meyer TA, Cumpston EC, Pelic J, Labadie, R. (2025), Characteristics of Hearing Loss in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis. Otolaryngol Head Neck Surg, 173: 1317-1327. https://doi.org/10.1002/ohn.1378
Caballero-Borrego M, Andujar-Lara I. Type 2 Diabetes Mellitus and Hearing Loss: A Prisma Systematic Review and Meta-Analysis. Otolaryngol Head Neck Surg. 2025;00(00):1-13. doi:10.1002/ohn.1346
