True confession: I have hearing loss. Significant enough that my audiology doctor prescribed hearing aids, a prescription that I never filled. Like most people, hearing aids aren’t covered by my health insurance, and, again like most people, I can’t afford them out of pocket. But that’s a story for another day.

As to the hearing loss itself, I had always thought it was the result of indiscretions of my youth: I spent a lot of time flying noisy little airplanes in an era when “real men” abstained from wearing headsets or other hearing protection. But as it turns out, I have a possible second risk factor. One that, ironically, I hadn’t heard about.

Yes, hearing loss is a documented, but lesser-known, complication of diabetes. At least for some people with diabetes (PWDs).

According to the American Diabetes Association (ADA), diabetes and hearing loss are two of American’s “most widespread health concerns.” The organization pegs the current diabetes prevalence at just north of 34 million people and hearing loss at 34.5 million. How much overlap is there?

Compared to research in other areas of diabetes, there’s really not all that much data on the combination of hearing loss and diabetes. In fact, it’s only recently been widely recognized that there’s a connection between the two at all.

Part of the problem is that most cases of diabetes are type 2, which often strikes older people, and most hearing loss strikes older people, too, so the overlap is difficult to parse out.

That said, groundbreaking research by Dr. Catherine Cowie and her team at the National Institute of Diabetes and Digestive and Kidney Disease (NIDDK), published in 2008, found that hearing loss is actually twice as common in adults with diabetes, leading the team to state that, “diabetes seems to be an independent risk factor for the condition.”

In short, it’s another diabetes complication.

Backing up this possibility, the ADA also points out that in the 88 million citizens with prediabetes, the rate of hearing loss is fully 30 percent higher than it is in non-diabetics.

But what about people with type 1 diabetes (T1D)? Are we affected, too? Well that’s complicated…

A 2018 study, headed up by Dr. David S. Schade of the University of New Mexico, looked specifically at T1D and hearing loss. It’s the largest study to ever actually measure hearing impairment in people with T1D, and it found, well, nothing.

Schade compared type 1s who were part of the Diabetes Control and Complications Trial (DCCT) trial to their spouses, who were used as the control group, and found that having T1D didn’t seem to make hearing any worse. Nor were there any differences in hearing between subjects who had been part of the DCCT’s intensive arm, and those in the conventional treatment arm.

Somewhat counter-intuitively, however, Schade’s data did find that “higher mean A1C over time was associated with hearing impairment.” In other words, while having T1D doesn’t seem to increase the risk of hearing loss, simply having higher blood glucose for extended periods of time does.

Of course, this is true of many of the more common “compilations” of diabetes, which might more correctly be called complications of elevated glucose. For instance, kidney, eye, and nerve damage are nearly non-existent in well-controlled diabetes. But interestingly, Shade’s results are starkly different from some studies of people with type 2 diabetes, which indicates that simply having diabetes appears to impact hearing negatively.

It might surprise you to “hear” that you might not realize you are losing your hearing. Hearing loss creeps up slowly over time, the changes gradual. The following is a list of warning signs that should alert you to the possibility of hearing loss:

  • Frequently asking others to repeat themselves
  • Having trouble following conversations that involve more than two people
  • Having trouble hearing the voices of women or small children
  • Thinking other people are mumbling
  • Being unable to hear, or have conversations, in busy/crowded/loud places like restaurants or bars
  • Turning the TV volume up loud enough that others complain
  • Suffering from tinnitus, a ringing/buzzing/humming sound in the ears
  • Feeling unusually exhausted after social gatherings or parties

The ADA recommends that PWDs be screened by an audiologist every 2 to 3 years if you are under age 50, and every year for those of us who can’t remember 50 — or if you already have some documented level of hearing loss.

In a report published in the Elsevier scientific journal Disease-a-Month in 2013, Dr. Oi Saeng Hong of the University of California San Francisco stated that the association between hearing loss and diabetes (at least type 2) is “now accepted.” She presented three “physiologically plausible theories” on the nuts and bolts of how the damage might occur: Microangiopathy, advanced glycation, and reactive oxygen processes.

  • Microangiopathy is a catch-all medical term for any disease of the capillaries. This theory, popular among experts, hypothesizes that hearing might be damaged by blood sugar in the same way that sugar damages the small blood vessels in the kidneys. Hong points out that the cochlea — the snail-shaped portion of the inner ear that receives sound vibrations — is “highly microvascular and considered vulnerable” to high blood sugar. She also points to research that shows a connection between PWDs with co-existing macroangiopathic kidney issues and hearing problems as “providing support for microangiopathy as a possible pathway to hearing loss in diabetes.”
  • The Glycation hypothesis springboards off of a study that shows glucose in the fluid in the ear can lead to tone deficits. “Extending the logic,” writes Hong, “repeated hyperglycemia may lead to chronic cochlear damage.”
  • The Reactive Oxygen, a.k.a. Oxidative Stress theory, suggests that elevated blood sugars, through oxidative stress, lower antioxidant protection in the body, such as that received from nitric oxide. This apparently has a role to play in protecting sensory hair cells in the ear that are critical to hearing and balance.

Which is it then? Maybe all of these causes. Hong concludes by saying, “hearing loss in diabetes is most likely a multifactorial process which may include more than one of the causative factors discussed here.”

Like all diabetes complications, the official advice from the experts is to tightly control your blood sugar, blah, blah, blah. And, of course, if it gets bad enough — and if you are covered or can afford them — consider hearing aids, which may help prevent further hearing loss.

At present, there aren’t any approved medications to treat hearing loss, but that may change as big pharma pursues this silent gold mine: Hearing loss impacts a total of 30 million people in the United States alone.

In the meantime, we’ve got a list of useful life hacks to help you deal with hearing loss:

  • Avoid exposure to loud noise. It can make hearing loss worse. Wear ear protection when mowing the lawn or using leaf blowers (or flying noisy little airplanes!).
  • Consider some changes to your diet. Research from Dr. Christopher Spankovich, published in the International Journal of Audiology, suggests that a varied diet, limited in fat and salt, may protect against hearing loss — even in people frequently exposed to loud noise.
  • Avoid certain medications. Ototoxic medications are drugs that can affect your hearing, some permanently. There are hundreds of these medications, including aspirin in large doses, NSAIDs like ibuprofen, many diuretics, certain blood pressure meds, tricyclic antidepressants, and even some antibiotics. Ask your doctor or pharmacist about the medications you take.
  • Have your ears cleaned. While experts caution against cleaning your own ears, especially with cotton-topped sticks, which can lead to worse problems, having the wax removed from your ears by a nurse at your doctor’s office is a good idea.
  • Take a break from media. This surprising idea comes to us from hearing aid maker Signia, which points out that, “Humans are not meant to live in places with constant sound. Turn off your music and television from time to time and enjoy the quiet. This gives your ears a chance to rest and recover. If you live in the city, spend a few hours every day with sound-canceling headphones or earplugs in.”
  • Use feng shui… sorta. You can help maximize your hearing by thinking about how you position yourself in a room, a la the principles of feng shui. Booths at restaurants, for example, tend to be more protected from background noise than open tables. Also, be sure to directly face those you want to talk to, as, working together, your ears channel sounds from directly in front of your face more effectively than from the side.
  • Deploy body language. Tune in to people’s unspoken “body language” to help you better interpret what people are saying. You can also learn, to some degree, to “read lips” to help you fill in gaps in your hearing.
  • Don’t be coy. If you have hearing loss, be sure your family, close friends, and coworkers know. That way, you won’t get the silent treatment. Being regularly left out of conversations and daily activities can have a host of other negative impacts, not least on mental health.