Does Hearing Loss Lead to Dementia?

Hearing loss and dementia are more common as you get older. The latest research shows that’s no coincidence. The two are linked.

Scientists are finding more and more evidence that trouble with hearing makes you more likely to go on to have dementia, a condition marked by memory loss and trouble with thinking, problem-solving, and other mental tasks.

That doesn’t mean that people with hearing loss (about two-thirds of adults over 70) are guaranteed to have dementia — simply that the odds are higher. There may be things you can do to lower your chances for mental decline, even if you start to have trouble hearing.

Scientists have found that a person’s chances for mental decline seem to go up the worse their hearing problems are. In one study, mild, moderate, and severe hearing loss made the odds of dementia 2, 3, and 5 times higher over the following 10-plus years.

And it seems to happen faster. Studies of older adults who had lost some hearing found that they had mental decline 30%-40% faster, on average. Looked at another way, they had the same mental decline in 7.7 years, on average, as someone with normal hearing showed in 10.9 years.

Researchers don’t know for sure how the two conditions are connected. Frank Lin, MD, PhD, of Johns Hopkins University, says three things may be involved:

• People with hearing loss tend to feel isolated, since it’s hard to join in conversations or be social with others when you can’t hear. Some research has shown a link between feeling lonely or isolated and dementia. So hearing loss may make mental decline happen faster than it would otherwise.
• Your brain has to work harder to process sound if you don’t hear well. That may take away resources that it could use for other important activities.
• If your ears can no longer pick up on as many sounds, your hearing nerves will send fewer signals to your brain. As a result, the brain declines.

“It’s likely a combination of all three,” says Lin, who has done much of the research on the connection between the conditions.

If you want try to lower your chances of hearing loss as you age, try to keep your heart healthy, protect your hearing from loud noises, and don’t smoke.

“Smoking is a big risk factor for sensory loss — vision and hearing,” says Heather Whitson, MD, at Duke Health.

Even when they take precautions, some people are simply more likely to get hearing loss in older age. In those cases, can using hearing aids protect you from dementia?

“That’s the billion-dollar question,” Lin says.

Lin is leading a 5-year clinical trial studying 850 people to see if hearing aids can cut dementia.

Even without the proof, Lin says there’s no downside to using hearing aids. In fact, there’s often a big upside to getting help for your hearing loss.

“With a very simple intervention, we could make a big difference improving quality of life,” Lin said.

In a pilot study, people with dementia started wearing inexpensive, over-the-counter devices to boost their hearing. A month later, their caregivers reported improved communication, more laughter, and more storytelling.

“If you’re an older adult with hearing loss, it would make sense to treat that hearing loss,” says Richard Gurgel, MD, of the University of Utah.

If you think your hearing has gotten worse with age, Gurgel recommends a hearing screening. The relatively quick, painless test can help you notice how your hearing changes as you get older and if a hearing aid would help you.