Is There a Relationship Between Hearing Loss and Alzheimer's

I am curious about posters I saw at one audiology clinic claiming a relationship between hearing loss and Alzheimer’s. I also saw that claim in other medical informational material. What are your thoughts/observations on this? Mom was legally deaf by the time she reached her late senior years and she developed dementia; however, I don’t know if the two are connected.

the first video might be what you are looking for

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It’s overblown and some of it was retracted. BUT there are multiple signs pointing into the possibility of any sensory deprivation, being a potential risk factor.
Recently I’ve seen research done on the sense of smell, and I’m sure than not many people think about that [keeping it engaged].
To sum it up, it’s been known for quite a some time than you need to keep your brain engaged, but now it seems that neglecting one area can serve as slippery slope into an illness.
Also, correlation doesn’t imply causation. There is a strong possibility that a co-factor [and an often unfortunate effect of being hearing impaired] is a social withdrawal, which is widely known component of not only mental health but longevity overall.

Most importantly, the link still isn’t definitely proven but it hasn’t stopped dispensers from using it as sales tactic. Judging how ethical it is, I’ll leave to you.

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I like the phase “sensory deprivation” I can tell you from my experience that my brain got lazy. I had an audiologist that helped me engaged the brain. At that time I was using closed caption on the TV and did not carry on a conversation on the phone. That audi sold me a bluetooth box that connected me with sound. The brain needs to hear sound. My brain got lazy and I could not make out words and still have some problems in certain situations. I have profound hearing loss. Now I have better hearing aids with bluetooth that help a lot with phone conversation. At that time I was only understanding every sixth word. I don’t use bluetooth with the TV anymore although I probably should. Since Covid I do Zoom a lot and with the help of Bluetooth I carry on conversations a lot more than before Zoom I don’t know if that helps but that is my experience. I can see that if a person has profound hearing loss for any length of time they could be misdiagnosed.

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This was very interesting; I still have to go back and finish watching the clip. My curiosity was peaked by what he said about cognitive decline such as visual/spatial perception, memory, organization, executive functioning and the coexistence of these challenges and hearing loss. I have a nonverbal learning disability (motor, visual perceptual/visuospatial, math, organization/executive functioning). Given that, generally, you are born with a learning disability, the hearing loss and diseased right ear that started in childhood was not the precursor to the cognitive decline; however, it is not beyond the realm of possibility that it exacerbated the learning challenges and vice versa. A third variable in this equation for me was environmental pollution in the form of sulphur and wood burning smoke and the eventual development of multiple chemical sensitivities. All three conditions have a neurological component (many chemicals are neurotoxic).

I went to a new audiologist on Friday and it was disconcerting to learn that my word recognition in my right (diseased) ear was only 30% and not functional, although I knew that ear was for decoration only, that’s why I got the CROS system. However, speech discrimination in my left (better ear despite sensorineural loss) was only 76%. Which is still good news for me (if I got 76% on an academic test I would be happy) but she explained I have trouble with consonants and high frequency sounds, which is a double bind because I have heightened senstivity to high frequency noise, so balancing the hearing aids has always been tricky. She said the hearing aids were a bit too soft, that’s why I’ve had such trouble with auditory processing and understanding speech. However, I felt reassured that the auditory processing deficit was related to the hearing loss and not likely due to any other disease like a brain tumour.

She also confirmed that I needed drops to clear up the mastoid cavity, so I went to a walk-in clinic yesterday and got some. I’m still waiting to be referred to an ENT specialist but the doctor said it was in progress.

I think Alzheimer’s is too closely associated with physical brain damage (amyloid buildup) for hearing impairment to play a very important role, even if “excess brain power”/extra brain reserve (whether acquired or innate) can somehow slow or even prevent the disease (plaque buildup) from having an impact (see the famous nun study; also there are some people with plenty ameloid aggregation in their brains who still function normally). And yes, social interaction appears to be part of maintaining “brain power”.

I actually think that the brains of people like us have to work far harder than others to follow conversations, as we are missing so many more sounds, thus building/maintaining “brain power” (this effort is partly a normal process- during speech, much is left unsaid, context, or swallowed.)
Finally, our brains may be wired differently- I process verbal information extremely slowly, but am a speed reader and rather good with visual clues.

Having said all this, the evidence that exercising our brains protects from dementia is still rather weak. Another conclusion from the nun study is still that our Alzheimer’s risk is set in stone at birth, or at best just after puberty.

There is also some recent, very interesting thinking about amyloid aggregation as a kind of primitive immune system (regular immune cells have poor access to our CNS, due to the blood-brain barrier), targeting bacteria that invade us from periodontitis, but that is a bit off-topic here:

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This is one of the reasons I stopped putting off getting HAs. My father resisted HAs for years past when he clearly needed them. He did eventually get them and a few years later was diagnosed with dementia. Of course it could be coincidence but both the sensory deprivation and the social withdrawal hypotheses make sense to me and I think it’s quite possible those years of not hearing hastened his dementia.

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That might be true up to some threshold of impairment and is probably only beneficial only up to some threshold of exertion. Because prolonged overexertion is NEVER good, be it mental or physical, and that’s what was linked to Alzheimer’s in some papers.

Correlation does not equal causality so I take such claims with many grains of salt! Because the hearing frequency spectrum has narrowed doesn’t mean that the brains stopped or even diminish processing sound. It just has a slight decrease in sound stimulus perhaps, and deft people will tell you that other senses increase consequently, so what you lose on one hand you gain on the other. In other words things aren’t so black and white. For all we know alzeimer has even been possibly linked to such things as common virus and like many complex syndromes as no single cause. Then remains the possibility of what lead to one also affects the other.

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I think it is hard to “overextend” our brains. Mastering how to extract info from incomplete auditory input really cannot be harmful. Also, such efforts more than compensate our sensorial deprivation for some frequencies (brainpower-wise). Brains in general are heavily taxed anyway, e.g. through education, learning a second (or third) language, how to play a music instrument, becoming a chess expert, you name it… None of such activities seem to predispose to Alzheimer’s, and may even protect us (the “reserve brainpower hypothesis”), even if the evidence is weak and, indeed, suffering from the correlation trap. I am not aware of viruses presenting a risk for Alzheimer’s either- but gingival bacteria appear to be (see above link).

The elephant in this chatroom is of course genetics. You really cannot be too careful when picking your parents.

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Still, I wonder about the 2023 Johns Hopkins study that found the prevalence of dementia was 61% higher among participants with moderate or severe hearing loss than among those with normal hearing. And higher for those with a more severe hearing loss.

All other possibilities for the development of Alzheimers aside this sounds like legitimate and significant statistics.

The only other suggestion above might be if there was a high correlation between both being born with hearing loss and having the dementia genes but this seems highly improbable given the many sources of hearing loss.

To me this sounds like a significant reason to not ignore getting and wearing ones hearing aids. Why risk or dismiss it?

Here is that study finding that HAs prevent dementia:

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(23)01406-X/abstract

I don’t have full-text access, but the most straightforward explanation is that this works by HAs reducing social isolation, a major, and well-established risk factor for dementia. The funny thing is that the authors do not mention that in their Abstract, the more so since the Johns Hopkins published on that latter link in another study:

https://agsjournals.onlinelibrary.wiley.com/doi/10.1111/jgs.18140

In the United States, an estimated 1 in 4 people over age 65 experience social isolation, according to the National Institute on Aging.”, so there you go.

The reverse could also easily be said, that the prevalence of hearing loss is higher with people who have dementia. Not to dismiss the benefit of mental fitness in minimizing the potential for dementia, which unfortunately isn’t popular in North American culture where physical fitness dominates the education system and music programs are cut back.

I think you are correct. It could be said too. There seems there could be a correlation between hearing loss and dementia.

Speaking of which my father who has been resistant to wearing his hearing aids was just diagnosed with dementia. He’s 89. He has the Phillips 9040s now and likes them better.

Myself, I finally started wearing hearing aids at 66 after knowing that I needed them for 12 years. I am wearing them religiously now.

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