The overlap between diabetes and hearing loss is poorly understood. This study aimed to test whether hearing loss is associated with known diabetes, new diabetes, pre-diabetes or metabolic syndrome.
1359 adults were randomly selected from households in rural Victoria, Australia. Participants completed a health survey and biomedical assessment including 75g oral glucose tolerance test (OGTT) with standard audiology testing. Rates of hearing loss (mild, moderate to severe) were compared in those with known diabetes, new diabetes, pre-diabetes and metabolic syndrome (defined using ATP III criteria). Pre-diabetes was defined as impaired fasting glucose (IFG) or impaired glucose tolerance (IGT).
Of the 1359 participants, 95 (7.0%) had some degree of hearing loss. Hearing loss occurred in 5.3% of participants with normal OGTT, 8.3% of participants with pre-diabetes, 13.3% of participants with new diabetes and 22.6% of participants with known diabetes. Hearing loss was more common in participants with increasingly abnormal glucose metabolism. When adjusted for age and gender, only the participants with known diabetes had a statistically significant relationship with hearing loss (p: 0.008). After adjusting for age and gender, and compared to those with normal OGTT, hearing loss was 2.30 (CI 1.24 – 4.29) fold more common in those with known diabetes. There was no significant relationship between metabolic syndrome and hearing loss.
Hearing loss is associated with known diabetes, but not significantly with new diabetes, pre-diabetes or metabolic syndrome. We postulate that hearing loss has a peripheral neuropathy/vasculopathy type relationship with diabetes.