Diabetes and Hearing Loss

Diabetes is a health condition where your body loses its ability to manage your blood’s level of insulin. This causes glucose to build up in your blood. Blood is a very important element to the health and functionality of several important organs. That’s why people with diabetes are at a very high risk for several health complications, including:

• Heart disease 
• Nerve damage
• Kidney damage
• Decreased eyesight
• Skin infections

Diabetes also affects your hearing organs, specifically your inner ear. Here’s how it works. 

The specific way that diabetes causes hearing loss is not clearly understood. It is believed that it ties back to the glucose levels in your blood. Too much glucose in your blood leads to hyperglycemia. 

In the long-term, having hyperglycemia slowly damages the blood vessels throughout your body. These blood vessels are necessary for producing the blood and blood cells that help the organs in your ear function. 

Studies have indicated that vascular and neural changes in the cochlea are likely the cause of hearing changes in people with diabetes. While it is clear that compromised cochlear blood supply can lead to cochlear dysfunction, details of injury mechanisms in diabetic hearing loss are subject to debate and yet to be thoroughly studied.

So the longer your diabetes and glucose levels are not kept under control, the more your hearing is likely to become damaged over time.

Type 2 diabetes happens later in people’s lives, and is not something you are born with like type 1 diabetes. It is linked to dietary issues where your body slowly loses the ability to produce enough insulin. For people with type 1 diabetes, they typically are born with an immune system that attacks their own pancreas. As a result they lose the ability early in their lives to produce their own insulin.

Type 2 diabetes is usually less severe because it is slow and less aggressive. Usually people with type 2 diabetes only lose a bit of their insulin production over time. However, that does not mean they do not face the same risk of having hearing loss.

How much does diabetes increase the risk of having hearing loss? There have been numerous studies and clinical research that have looked into this question. 

There was a research survey conducted in the United States from 1999 to 2004, and published in 2008. It looked at more than 5,000 people as the test group. The results of the research found that hearing loss appeared in 21% of people who had diabetes, compared to only 9% of people who did not have diabetes. 

Another study in 2012 analyzed the results of 13 separate studies with more than 20,000 trial subjects. It confirmed that people with diabetes were twice as likely to have hearing loss than those who do not have diabetes. The risk factor was found to be higher in people who are younger than 60 years old. This is likely due to the fact that as you are older than 60, you face a greater risk of age-related hearing loss. When you are younger, diabetes is a more common cause.

Just because you have diabetes does not guarantee that you will lose your hearing. Diabetes is just a risk factor, not a direct cause. You are far more likely to develop hearing loss when you do not properly manage your diabetes. The more you let it go untreated and don’t manage the insulin levels in your blood, the greater the risk becomes.

So if you have diabetes and want to preserve your hearing, there are some things you can do to lower the risk.

The first tip is to avoid common diabetes risk factors that can increase the risk  of hearing loss. The most common issues you have direct control over include:

• Maintain optimal general health through diet and exercise
• Keep your weight under control to avoid obesity

Other risk factors, such as age, are beyond your ability to avoid. But being able to limit your risk of hearing loss with things you can control is important.

You can also reduce the risk of your diabetes causing hearing loss by making sure to keep the glucose level in your blood under control. If you keep the glucose levels in your blood in a normal range, you won’t become hyperglycemic. If you never become hyperglycemic, you won’t cause damage to the blood vessels in your hearing organs. Here are some common tips given to people with diabetes from Diabetes Canada: 

• Monitor your glucose levels regularly, every four hours at least
• Always take your medication or insulin injections as prescribed by your doctor
• Avoid foods and drinks (carbs and sugars) that can cause your glucose levels to spike
• Consume more food and drink that can lower glucose levels, like fiber and whole grains
• Exercise regularly, as your muscles burn glucose for energy and exercise helps your body use insulin more efficiently
• Manage your stress, because it causes your body to produce stress hormones that affects glucose production
• Get more sleep, as sleep deprivation can cause your body to produce those same stress hormones

You can also speak with your doctor for additional tips on managing your glucose levels. They can help recommend specific diet or wellness routines that have been proven to help people with diabetes. 

Diabetes is a health condition that increases the risk that you also develop hearing loss. It will not automatically cause hearing loss, however. If you can keep the glucose levels in your blood at a normal level, you are far less likely to have hearing loss. Managing your condition takes work and dedication to follow a healthy routine set out by your doctor.

If you or a loved one have diabetes, it is recommended that you get a hearing test at least once every two years regardless of your age. This will help monitor your overall hearing health and catch early signs of hearing loss before it becomes too severe. 

¹ Bainbridge KE, Hoffman HJ, Cowie CC. Diabetes and Hearing Impairment in the United States: Audiometric Evidence from the National Health and Nutrition Examination Survey, 1999 to 2004. Ann Intern Med. 2008;149:1-10.

*National Health and Nutrition Examination Survey, 1999 to 2004. 5,140 (3,316 males; 2,624 females) noninstitionalzied adults age 20 to 69 years who had audiometric testing. Hearing impairment was assessed from the pre tone average of thresholds over low or mid-frequencies (500, 1000, and 2000 Hz) and high frequencies (3000, 4000, 6000, and 8000 Hz) and was defined as mild or greater severity (pure tone average >25 decibels hearing level [dB HL]) and moderate or greater severity (pure tone average >40 dB HL). Hearing impairment was more prevalent among adults with diabetes. Age-adjusted prevalence of low- or mid-frequency hearing impairment of mild or greater severity on the worse ear was 21.3% (95% CI, 15.0% to 27.5%) among 399 adults with diabetes compared with 9.4% (CI, 8.2% to 10.5%) among 4741 adults without diabetes. Similarly, age-adjusted prevalence of high-frequency hearing impairment of mild or greater severity in the worse ear was 54.1% (CI, 45.9% to 62.3%) among those with diabetes compared to 32.0% (CI, 30.5% to 33.5%) among those without diabetes. The association between diabetes and hearing impairment was independent of known risk factors for hearing impairment, such as noise exposure, ototoxic medication use, and smoking (adjusted odds ratios for low- or mid-frequency and high-frequency hearing impairment were 1.82 [CI, 1.27 to 2.60] and 2.16 [CI, 1.47 to 3.18], respectively). The diagnosis of diabetes was based on self-report. The investigators could not distinguish between type 1 and type 2 diabetes. Noise exposure was based on participant recall.¹

Fukushima, Hisaki, Sebahattin Cureoglu, Patricia A. Schachern, Takeshi Kusunoki, Mehmet F. Oktay, Naomi Fukushima, Michael M. Paparella, and Tamotsu Harada. “Cochlear Changes in Patients with Type 1 Diabetes Mellitus.” Otolaryngology - Head and Neck Surgery. No longer published by Elsevier, July 15, 2005. https://www.sciencedirect.com/science/article/abs/pii/S0194599805002238. 

Ren, Tianying, Nadine J. Brown, Minsheng Zhang, Alfred L. Nuttall, and Josef M. Miller. “A Reversible Ischemia Model in Gerbil Cochlea.” Hearing Research. Elsevier, April 21, 2000. https://www.sciencedirect.com/science/article/pii/0378595595001921.