Tag Archive: dementia

Can noise exposure influence the risk of dementia?

Photo credit: Oleg Magni from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

Can noise exposure influence late-life cognition and the risk of developing dementia? That the answer might be “Yes” is suggested by a study in the latest issue of the medical journal Alzheimer’s & Dementia, the journal of the Alzheimer’s Association. I have read the article, although only the abstract is available at the link.

Researchers analyzed data collected from the Chicago Health and Aging Project, looking at 5,227 participants in the study. Noise exposure levels were estimated using accepted modeling techniques, and cognitive performance was measured using standardized tests. The populations in the four quartiles of noise exposure were largely similar in terms of ethnicity, socioeconomic status, smoking, alcohol consumption, physical activity, and body mass index.

Noise exposure level was correlated with mild cognitive impairment and Alzheimer’s disease. An increment of 10 A-weighed decibels* in noise corresponded to 36% higher odds of mild cognitive impairment and 29% higher odds of a diagnosis of Alzheimer’s disease.

It is important to note that this is among the first studies of community noise and cognitive decline, the first such study done in the United States, and perhaps most importantly, that correlation does not mean causation.

But as the authors note, there are animal studies showing brain changes with noise exposure, and as I have noted many times, there is no evidence that unwanted noise exposure has any beneficial effects on humans or animals.

*A-weighting adjusts the frequencies in sound to match those heard in human speech.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Another study shows association of hearing loss with cognitive decline

Photo credit: Xiaofan Luo licensed under  CC BY-NC-SA 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

We have reported previously on associations between hearing loss and dementia in the U.S., and studies finding brain changes associated with decreases in auditory input due to hearing loss. Hearing loss is also associated with depression.

This study from China, published in JAMA Network Open, confirms these associations in a different population. The China Health and Retirement Longitudinal Study is following a nationally representative survey of adults age 45 and older, and their spouses. The current study looked at data from 18,038 participants with an average age of 59.9. Hearing impairment was associated with worse performance in episodic memory, mental intactness, and global cognition and a greater risk of depression.

Correlation is not causation, but this report from another country with a different language and culture confirms studies in the U.S. and Europe. It’s another piece of the puzzle in trying to understand why some people develop certain problems as they age. Research is ongoing to elucidate how hearing loss contributes to or causes cognitive decline, and whether providing hearing aids can prevent or slow cognitive decline.

In the meantime, we urge people to protect their hearing as assiduously as they protect their vision. We don’t stare at the sun. We wear sunglasses when outdoors. And we should view hearing loud noise just like staring at the sun. Loud noise is as dangerous for the ears as the sun is for the eyes.

Because if something sounds loud, it’s too loud, and auditory health is in danger.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Poor hearing associated with brain changes

Photo credit: Andrea Piacquadio from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

Bryan Pollard, founder of Hyperacusis Research, Ltd., is an electrical engineer. Almost every time I have discussed something with him, he asks me an important question: “What’s the cause? What’s the effect?”

It is very easy to make a mistake thinking that an association is causal when it is not.

One of the best ways to avoid making this mistake is to study a phenomenon over time. If a factor in some research subjects is associated with changes over time, and absence of that factor is not associated with the change being examined, causality is more likely.

A good example of this question is the association of hearing loss with the development of dementia. Maybe hearing loss causes dementia because there is decreased nerve stimulation of certain parts of the brain related to auditory and speech processing, but maybe the brain changes are independent of hearing loss or perhaps even the cause of the hearing loss.

This recent report in JAMA Otolaryngology-Head and Neck Surgery, with an accompanying editorial, uses the study of brain changes over time to try to answer this question. The research was done on the well-studied population of the Baltimore Longitudinal Study of Aging. Hearing tests and studies of brain tissue using specialized research techniques were done. Imaging was done by MRI at the National Institute of Aging.

Results showed that poorer hearing at baseline was associated with specific changes in portions of the brain processing auditory input, but not in other areas of the brain. The editorial notes the limitations of the study and its preliminary nature, but the report is another piece of the puzzle linking hearing loss to dementia.

For at least five years, I have been saying, “If it sounds too loud, it IS too loud.” But based on the accumulating evidence of the dangers of noise for hearing loss, and then the impact of hearing loss on social function, economic success, and the development of dementia, I’ve decided to change my advice.

Now I would say, “If it sounds loud, it IS too loud.”

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Noise and air pollution may be preventable causes of dementia

Photo credit: Elina Krima from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

Noise and air pollution may be preventable causes of dementia. This new study from the Alzheimer’s Association International Conference, reported by Med Page Today, discusses risk factors contributing to dementia. Other than rare genetic conditions, most cases of dementia have multifactorial causation. This makes prevention difficult because multiple risk factors must be addressed.

In general, a healthier lifestyle, including not smoking, eating a Mediterranean style diet, daily exercise, and other similar behaviors, have been shown to reduce or delay the onset of dementia. The new study found that risk factors contributing to dementia include hearing loss, social isolation, depression, and air pollution. These factors have now also been added to the Lancet Commission’s list of key modifiable risk factors for dementia.

Although the study doesn’t mention noise explicitly, noise causes hearing loss. Hearing loss in turn is associated, likely causally, with social isolation. People who can’t understand what others are saying tend to avoid social interaction because it’s too stressful or too embarrassing not to understand what others are saying. Social isolation in turn leads to depression.

With regard to hearing loss, researchers think the loss of auditory input caused by hearing loss also causes changes in the brain that contribute to the development of dementia. Previous studies led by researchers from Johns Hopkins have shown that hearing impairment in people 45-65 years old is related to a progressive loss of nerve cells in brain structures and reduced microstructural integrity that may indicate early Alzheimer disease.

The precise mechanisms by which air pollution contributes to dementia are unclear, but there are strong correlations between levels of pollutants and dementia. Much if not most of urban air pollution comes from particulate matter emitted by internal combustion engines. These are also a major cause of urban noise.

Reducing noise will prevent hearing loss and its consequences. And if noise from vehicles and other engines is reduced, air pollution will also be reduced.

As we have been saying for some years now, a quieter world will be a healthier world for all.

And, one hopes, it will also be a world with less dementia.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Dementia isn’t inevitable, and neither is hearing loss

Photo credit: Andrea Piacquadio from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

This new study from the Alzheimer’s Cohorts Consortium, published on an open access basis in the medical journal Neurology, reports that dementia rates appear to be on the decline in Europe and North America. Analyzing results from seven different research studies, the Consortium found that the incidence of dementia declined 13% per decade in the last 40 years, with a confidence interval of 7-19% per decade. The decline was more pronounced in men than in women.

It is difficult to find the cause for the decline, but the researchers think it is due to a focus on treating cardiovascular risk factors, including reductions in smoking, better blood pressure control, and the use of antithrombotic medication. The article states, “[w]hile none of these has been specifically intended to halt cognitive decline, decades of cardiovascular risk management have likely had substantial effects on brain health, supported by reduction of small-vessel disease on brain imaging in more recent years.“

Why am I writing about a decline in dementia in a blog about noise issues?

Is it because research shows that hearing loss is a possible contributing factor to the development of dementia? No, although that statement is accurate.

The reason is that dementia used to be thought of as an inevitable part of aging, but that’s not true. Many cases of dementia have a vascular cause, and can be prevented by treating cardiovascular risk factors.

Similarly, hearing loss is thought to be part of normal aging, as shown by the use of the terms “age-related hearing loss” and “presbycusis”.

I presented a paper at the 12th Congress of the International Commission on the Biological Effects of Noise in Zurich in 2017, reviewing literature that showed that hearing loss was not an inevitable part of aging but largely represented noise-induced hearing loss. A recent research paper from the Massachusetts Eye and Ear Infirmary confirms that conclusion using ear tissue from post-mortem specimens.

I’ve said this before, but it bears repeating: If a noise sounds too loud, it is too loud.

If you protect your hearing–by avoiding loud noise and using hearing protection when you can’t–you should be able to hear well when you get old. And maybe you’ll reduce your chance of developing dementia, too.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Can hearing aids help prevent dementia?

Photo credit: Vilma Liella licensed under CC BY-SA 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

Can hearing aids help prevent dementia? This comprehensive article in the New York Times magazine section discusses the research suggesting that they might.

Of course, it’s far better to prevent hearing loss in the first place by avoiding loud noise exposure or using earplugs if one can’t avoid the noise. And it’s far cheaper, too.

There are smart phone sound meter apps to measure ambient noise levels, but one doesn’t need a sound meter to know if it’s too loud. If the noise is loud enough to interfere with conversation at the normal social distance of 3 to 4 feet, it’s loud enough to damage your hearing.

Just remember: if it sounds too loud, it is too loud!

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Can hearing aids delay development of dementia?

by Daniel Fink, MD, Chair, The Quiet Coalition

Can hearing aids delay the development of dementia in older people? This question has been discussed since research showed an association between hearing loss and dementia, with greater hearing loss being associated with a greater chance of dementia. This study indicates that the answer may be “yes.” 

The study is based on insurance claims data, not clinical data, so clinical studies are needed to confirm the results. But in analyzing data on 79 million adults insured by a private health insurance company, hearing aid use among adults diagnosed with hearing loss was associated with a decreased risk of Alzheimer’s disease or dementia.

Hearing loss leads to lack of brain stimulation, social isolation, and depression, all of which have been linked to development of dementia. So the results of the study make sense. It’s possible that treating hearing loss with hearing aids may help delay or prevent dementia.

Of course, preventing hearing loss in the first place is far better and far cheaper than providing hearing aids to those with hearing loss, and certainly cheaper than treating dementia. And preventing most hearing loss is easy: avoid loud noise exposure or wear hearing protection if one can’t.

Because if something sounds too loud, it is too loud.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Association of hearing loss with dementia

Photo credit: Fechi Fajardo licensed under CC BY 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

This article in JAMA Network Open reports an association of hearing loss with the development of dementia in Taiwan. Similar associations have been reported in the United States.

Prevention of hearing loss and provision of hearing aids might help, but I prefer prevention in the first instance.  After all, prevention is almost always better and cheaper than treatment, especially for auditory disorders, and noise-induced hearing loss is 100% preventable.

So to preserve your hearing and more, avoid loud noise or use hearing protection if you can’t. And remember: if something sounds too loud, it IS too loud.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Can preventing hearing loss now prevent dementia later?

Photo credit: Monica McGivern licensed under CC BY-ND 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

We have written about this report before but important news bears repeating: A study using functional MRI techniques found that relatively young people with very mild hearing loss were using parts of their brain not normally used to try to understand speech. The researchers think that this added stress on the brain now may lead to an increased rate of dementia later.

The relationship between hearing loss and dementia is being studied in many ways. It has long been known that there was a correlation between hearing loss and dementia, with studies showing that people with worse hearing are more likely to develop dementia.

And one large study is trying to see if giving hearing aids to older people with hearing loss prevents dementia.

But it’s a whole lot easier–both a whole lot better, and a whole lot cheaper–to just avoid hearing loss by avoiding loud noise now. Hearing loss, after all, is not an inevitable part of aging.

Remember: if it sounds too loud, it IS too loud.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America. Dr Fink also is the interim chair of Quiet Communities’ Health Advisory Council, and he served on the board of the American Tinnitus Association from 2015-2018.

Hearing loss in young people changes brain function

by Daniel Fink, MD, Chair, The Quiet Coalition

Since I became a noise activist and started learning about the dangers of noise, I have been predicting an epidemic of noise-induced hearing loss (NIHL) in young people due to their ubiquitous use of personal music players with associated headphones or earbuds, often turned up loud enough to annoy me when they walk past. This article reports that young adults with subtle hearing loss also have brain function changes detected on functional MRI scans.

We don’t just hear sound with our ears. We have to process the information from the ear in the brain. According to this study, hearing loss makes the brain work harder.

There is a well-known association between hearing loss and dementia, with worse hearing being correlated with a greater risk of developing dementia. And it now looks like this problem starts in early adulthood, not late in life.

So unfortunately, I’m going to predict that there will not only be an epidemic of NIHL when today’s young people reach midlife–in their 40s and 50s, not in their 60s, 70s, and 80s–but there will also be an epidemic of early-onset dementia.

When will the public health authorities and regulators–the FDA, CDC, and Consumer Product Safety Commission–take necessary action to protect our young people?

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He serves on the board of the American Tinnitus Association, is the interim chair of Quiet Communities’s Health Advisory Council, and is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.