While some diabetes-related complications are well-known (e.g., potential eye, kidney or nerve damage), there are others, like auditory neuropathy, that are largely unknown. Chronic hyperglycemia can cause auditory neuropathy when associated with damage to smaller auditory nerves (those that enable hearing).
Assessing the risk
Many studies indicate that some people with type 1 diabetes (T1D) have a higher auditory threshold, which means they need sounds to be louder in order to hear them. Studies on this subject have yielded significantly varying results, showing that about 5% to 48% of people with T1D have hearing loss.
While it’s unclear exactly how many people with T1D experience this complication, there is an unmistakable link between diabetes and hearing loss.
Researchers generally agree that the number of years with diabetes is a major risk factor for hearing loss. One study indicates that the risk increases by 1.7% yearly for people with T1D, while it increases only by 0.89% for the general population. However, the level of hearing loss observed in different studies was generally so low that participants hadn’t noticed it before. This could be why auditory neuropathy is not identified as a potential diabetes-related complication.
The best way to avoid or slow down these complications, including the risk of hearing loss, is to maintain an adequate glycemic balance.
Preventive screening
Given that auditory neuropathy often goes unnoticed and that it’s associated with an increase in hemoglobin A1c (Hba1c) levels, an auditory evaluation could be useful whenever the HbA1c level (determined through a blood test) of a person with T1D has been above range for many years.
Reference:
- Mujica-Mota, M. A., Patel, N., & Saliba, I. (2018). Hearing loss in type 1 diabetes: Are we facing another microvascular disease? A meta-analysis. International Journal of Pediatric Otorhinolaryngology, 113, 38–45. https://doi.org/10.1016/j.ijporl.2018.07.005
- Lasagni, A., Giordano, P., Lacilla, M., Raviolo, A., Trento, M., Camussi, E., … Zanone, M. M. (2015). Cochlear, auditory brainstem responses in Type 1 diabetes: relationship with metabolic variables and diabetic complications. Diabetic Medicine, 33(9), 1260–1267. https://doi.org/10.1111/dme.13039