Tag Archive: hearing loss

There is nothing inevitable or natural about chronic disease

Photo credit: Robbie Sproule licensed under CC BY 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

This thoughtful piece talks about chronic disease, pointing out that it is not inevitable or natural. The author, Dr. Clayton Dalton, writes that:

[T]raditional cultures across the globe, from hunter-gatherers to pastoralists to horticulturists, have shown little evidence of chronic disease. It’s not because they don’t live long enough – recent analysis has found a common lifespan of up to 78 years among hunter-gatherers, once the bottlenecks of high mortality in infancy and young adulthood are bypassed. We can’t blame genes, since many of these groups appear to be more genetically susceptible to chronic disease than those of European descent.

So what is the reason for the absence of chronic illness among these cultures? “Evidence suggests it is how they live,” Dr. Dalton replies. And what factors do these different cultures share?  Dr. Dalton writes that the “common denominator [is] defined by the absence of modern banes: absence of processed foodstuffsabsence of sedentary lifestyle, and likely absence of chronic stressors.”

Dr. Dalton doesn’t specifically mention noise-induced hearing loss, but that’s another chronic disease that he could have included in his essay.

I spoke about this at the 12th Congress of the International Commission on the Biological Effects of Noise in Zürich in June. Similar to Dr. Dalton’s comments about hypertension and diabetes, I presented information showing that significant hearing loss is probably not part of normal aging, but represents noise-induced hearing loss.

A useful analogy for noise and hearing is sun and the skin. It turns out that skin and subcutaneous tissues sag as we age–that’s normal–but deep wrinkles, age spots, and skin cancers are the result of ultraviolet exposure. Similarly, I’m sure there are changes that occur in our hearing as we age, but profound hearing loss (25-40 decibel decrement in hearing) is most often the result of noise exposure.

In the end, how we live our lives matters. If we want to hear well into old age, we have to work to preserve our hearing all during our lives. How? It’s easy: avoid loud noise or wear ear protection if you can’t.

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.

Hearing loss is an occupational health hazard for musicians

by Daniel Fink, MD, Chair, The Quiet Coalition

It’s not surprising that hearing loss is an occupational health hazard for musicians, as highlighted in this recent report. After all, noise causes hearing loss. It doesn’t matter if the noise is from machinery in a factory, from a jet engine on the tarmac, or from loudspeakers at a rock concert. Whatever the source, the effect is the same.

And the type of music doesn’t matter, either, as noise-induced hearing loss is a problem for classical musicians, too.

The bottom line is this: hearing is precious. If hearing music is important to you–or hearing children or grandchildren speak, birds sing, whatever it is–protect your hearing.

How can you protect yourself? It’s easy. The auditory injury threshold is only 75-to-78 A-weighted decibels. That’s about the level at which ambient noise makes conversation difficult. If you are having a hard time having a conversation because of the ambient noise around you, it’s too loud. And if something sounds too loud, it IS too loud! Turn down the volume, leave the noisy place, always carry earplugs with you, and use them!

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.

The unintended consequences of (failed) diplomacy

 

U.S. Embassy in Havana, Cuba (photo: U.S. State Department)

, McClatchy, reports on the mystery surrounding a sonic device used against U.S. and Canadian diplomats stationed in Cuba that caused hearing loss. Johnson writes that it is known that the “U.S. military deploys nonlethal noise and radiation weapons to incapacitate aggressors,” like a device that “can hit you with sound that will make you not be able to stand up” or that can “literally heat up water molecules under the skin’s surface.” And, of course, “[r]esearchers have also experimented with ultrasonic and infrasonic frequencies above and below the level at which humans can hear,” which, in some cases, “can cause physical discomfort at high intensity.” “They call them brown tones,” said Vahan Simidian, the CEO of HPV Technologies Inc., a firm that makes “long-range speakers that can send sound as far as two miles.” Why do they call them brown tones? Because they “can make you sick to your stomach.” And you can guess what happens next.

But the device used in Cuba was different. How? This device caused hearing loss in those it targeted. So why did Cuba purposefully deafen the diplomats? Vince Houghton, an intelligence historian employed by the International Spy Museum, speculates that it was a run-of-the-mill harassment campaign that got out of hand. Says Houghton:

The most likely scenario to me is this was used to harass, to annoy, to kind of goof off and be, like, ‘Ha ha! Let’s make them sick to their stomach. Let’s make them dizzy.’ And then, ‘Oh crap, it went too far…’

Houghton also believes that someone else was involved in developing this weapon, because the technology would be too “resource intensive” for “cash-strapped Cuba.”

The Cuban government responded by stating that it “has never permitted, nor will permit, that Cuban territory be used for any action against accredited diplomatic officials or their families, with no exception.” Meanwhile, The Washington Post reports that “investigators were looking into the possibilities that the incidents were carried out by a third country such as Russia, possibly operating without the knowledge of Cuba’s formal chain of command.”

The only good news from this twisted tale is that the unknown sonic device was probably intended only to harass, not disable. But when we read this piece our first thought was this: what if the resources marshalled to create this and the other appalling sound-based weapons were spent instead on educating the public on how to protect their hearing or distributing ear protection to vulnerable populations? That is, why do we accept that there is always money for weapons, but so little for public health?

Thanks to Bill Young, PhD, a noise reduction advocate from Stamford, Connecticut, for the link to The Washington Post article.

Treating hearing loss may help prevent dementia

By Daniel Fink, MD, Chair, The Quiet Coalition

A recent Canadian newspaper article discussing a report in The Lancet, the premier British medical journal, about preventing dementia.

The Lancet article highlights the importance of treating hearing loss for possibly preventing dementia. If you’re interested in dementia, know someone with dementia, or want to see what you can do to avoid developing dementia yourself, I recommend the Lancet article. It summarizes a large body of research in a readable fashion that should be accessible even to the lay reader.

There are many factors correlated with dementia risk, including genes, blood lipid levels, and diseases or conditions such as diabetes, hypertension, obesity, and factors such as social isolation and cigarette smoking. The association between hearing loss and dementia is well-known and research is under way to see if treating hearing loss reduces the risk of dementia. Despite only correlations, and no clear understanding of how hearing loss may increase the risk, the Lancet authors think the scientific evidence is strong enough to recommend treatment of hearing loss as a possible prevention measure for dementia.

Of course, the only treatment for hearing loss is hearing aids, with cochlear implants reserved for the more severely impaired. We think that people with hearing loss should use hearing aids just to be able to hear others, whether hearing aids prevent dementia or not.

That said, hearing aids are a poor substitute for preserved natural hearing.

Perhaps the Lancet article should have gone a step further and highlighted the importance of preventing noise-induced hearing loss (NIHL) to delay or avoid the onset of dementia. After all, we think it’s significantly better to prevent NIHL than to treat it, and that’s simple: avoid exposure to loud noise or wear ear protection when you cannot.

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.

When “good news” is bad news

Daniel Fink, MD, Chair, The Quiet Coalition

This article in JAMA Otolaryngology about hearing loss in young people age 12-19 is getting press as good news. Researchers at the University of California (both the Los Angeles and San Francisco medical schools) analyzed audiometric test data on young Americans from the National Center for Health Statistics collected by National Health and Nutrition Survey (NHANES). The researchers concluded that the prevalence of hearing loss as measured by standard pure tone audiometry had not increased despite wider use of headphones and earbuds to listen to personal music players.

We don’t think this is good news at all.

First, the researchers state that the prevalence of hearing loss in 2009-2010 is 15.2%. Hearing only worsens with age, so based on the data, it appears that about one-sixth of young people are likely to have profound hearing loss in mid-to-late life. If they were losing their vision instead, would anyone think this was good news?

Second, the subjects hearing was assessed by standard pure-tone audiometry. These traditional tests do not detect hidden hearing loss, which indicates nerve damage (synaptopathy) caused by noise exposure. Only techniques that are now considered research techniques will detect this early auditory damage.

Third, the authors note that there was increased risk of hearing loss in racial/ethnic minorities and those from low socioeconomic backgrounds. Isn’t hearing health an issue for this group of Americans too?

Finally, the researchers discuss the many limitations of this type of data analysis, which means that no definite conclusions can be drawn from this study.

In the end, the article generated a lot of “good news” headlines and in doing so has done a disservice to all young people, because those headlines and the cursory reports that followed downplay the dangers of increased headphone and earbud use. This is particularly galling and irresponsible when one recognizes that noise-induced hearing loss is 100% preventable.

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.

New Zealand researchers agree: hearing loss is probably a dementia risk factor

By Daniel Fink, MD, Chair, The Quiet Coalition

Many people don’t understand the process of medical and scientific research and how different hypotheses are developed and tested, using different methods in different human populations with animal studies when possible, until a consensus is reached. This was how researchers–including doctors, epidemiologists, researchers using animal models, and scientists doing basic research at the cellular, molecular, and genetic levels–figured out that cigarette smoke causes cancer and many other diseases, and how it does this. Despite the broad scientific and public health consensus, there are still skeptics, such as those at the conservative Heartland Institute, who say there is still doubt about whether smoking causes lung cancer. There is also a Flat Earth Society. Many Americans think that evolution is an unproven theory despite more than a century of research and strong evidence supporting evolution.

For the rest of us who believe in evidence-based science and evidence-based social and economic policies, our understanding of reality is always evolving based on the evidence. Sometimes something long thought to be true is found not to be correct after all. In medicine, one of the best examples may be ulcers in the stomach and small intestine, which for decades were thought to be caused by too much stomach acid but were found to be caused by bacteria. Australians Barry Marshall and J. Robin Warren won the Nobel Prize in 2005 for making this discovery. But most of the time an early hypothesis is confirmed by one study, and then another, and then by studies in animal models, and then by basic science research, until a broad consensus is reached.

This is what is happening with the hypothesis that hearing loss is associated, probably causally, with dementia. Dr. Frank Lin at Johns Hopkins University may be the best-known researcher in this field but other researchers in other countries are studying the same question. This report from New Zealand discusses what is being done there. And this report from the UK discusses research presented there.

It’s always good to have confirmation of research by different researchers using different techniques in different populations. Such confirmation helps validate initial findings in one population and helps move our understanding forward. We know that noise exposure causes hearing loss. If hearing loss is shown to be causally associated with the development of dementia, then preventing hearing loss should help to also prevent dementia. One theory is that the brain needs input to maintain function, and without auditory input and/or social connections, brain function declines. Another theory is that whatever degenerative process causes hearing loss also causes loss of mental function. Ongoing studies, providing hearing aids to those with hearing loss but not to others and then measuring intellectual function over time, may elucidate the cause-effect relationship. Regardless, we don’t need to wait for more evidence for the link. Preserving one’s hearing should be enough reason to avoid loud noise or to wear ear plugs if you can’t.

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.

Why do humans suffer hearing loss from noise?

Image is in the public domain in the U.S.

By Daniel Fink, MD, Chair, The Quiet Coalition

Why do humans suffer hearing loss from noise? The cellular, sub-cellular, and even molecular reasons for how noise damages the auditory system are known, but why?

In a fascinating article in The Hearing Journal, evolutionary biologist William Shofner, PhD, notes that humans and our animal forebears evolved in a largely quiet environment. Exquisitely acute hearing was important for finding prey or avoiding threats, but resistance to noise damage in the auditory system conferred no selective advantage.

Our world only started getting noisy as cities evolved, and especially since the Industrial Revolution. That is, our ears haven’t evolved to handle the noise, hence the epidemic of noise-induced hearing loss reported by Centers for Disease Control and Prevention.

Shofner’s last paragraph says it all:

Why didn’t evolution make the ear more noise-resistant? Again, evolution does not proceed with purpose. Simply stated, the human ear did not evolve under conditions of high sound levels. Any genetic mutation that might have led to a noise-resistant ear was likely not selected because it did not provide any benefit for survival and reproductive success in the pre-historic acoustic environment of early mammals. Natural selection is an exceedingly slow process that occurs over many generations, and the susceptibility of the human ear to noise-induced damage shows how natural selection is unable to keep up with rapid changes in an organism’s environment (Evol Applications. 2008). Technology has produced an acoustic environment that has changed much faster than the sluggish pace of human evolution. This evolutionary explanation of why the human ear is so susceptible to damage at highly intense noise levels provides a valuable perspective that audiologists can offer patients to prevent NIHL.

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.

New explanation for why older people can’t hear in noisy environments

Photo credit: Filipe Fortes licensed under CC BY-SA 2.0

By Daniel Fink, MD, Chair, The Quiet Coalition

There are already several explanations about why middle-aged and older people can’t understand speech in noisy environments. One may just be high-frequency hearing loss caused by noise, which makes it hard to hear the higher-pitched consonant sounds (F, S, SH, T, V) that allow us to differentiate similar sounding words (Fear, Sear, Shear, Tear, Veer). (See the graph in this CDC Vital Signs Issue.) Another reason may be a phenomenon called “hidden hearing loss,” which is caused by noise damage to nerve junctions (synapses) in the inner ear.

And now a new report indicates that there may also be a brain or central processing problem. A study conducted at the Max Planck Institute in Germany, “analyzed what happens in the brain when older adults have trouble listening in loud environments.”  The researchers “monitored the brains of 20 younger adults ages 18 to 31, and 20 older adults in their 60s and 70s, during a listening task” in which constant background noise was played while participants were told to focus on certain targeted sounds.

What the researchers found was that “the younger adults were able to zero in on the target signals while filtering out the irrelevant noise,” but the older participants had “a harder time tuning out the background noise.” What remained unclear was whether the “degradation of the ear’s ability to hear actually leads to a decline in the brain’s ability to filter out noise and hear a single sound,” or whether “the brain’s listening ability erodes independently of any changes going on in the ear.”

As for why older people have a difficult time understanding speech in noisy environments, it most likely is that all three factors occur to varying degrees in various individuals. But one thing is certain, preventing hearing loss is simple: avoid loud noise. And improving the ability of people young and old to follow conversations is also simple: turn down the volume in indoor places.

Link via the UK Noise Association.

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.

 

Millions of people don’t protect their ears

Photo credit: Quinn Dombrowski licensed under CC BY-SA 2.0

By Daniel Fink, MD

Noise is a medical and public health problem, and yet people ignore it at their own peril. Most of us are exposed to too much noise every day. That may explain why the Centers for Disease Control and Prevention found that about 25% of adults age 20-69 had hearing loss, and that many people with hearing loss didn’t know they had it.

Which is why a recent article by Mark Fischetti in Scientific American,A Loud Warning: Millions of People Do Not Protect Their Ears,” is particularly disturbing. Fischetti reports that while “many people know that they should use earplugs or earmuffs when mowing the lawn or partying at the club,” they don’t protect their ears against noise at home or at work. If you click the link to the article, you’ll see a frightening infographic that very clearly shows that millions of Americans are at risk of losing their hearing or suffering other hearing damage because they fail to protect their ears.

Maybe if people knew that noise caused hearing loss, tinnitus, and hyperacusis–none of which can be cured–they might be motivated to protect their hearing and fight for quiet.

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.

Experts: Hearing loss is on the rise among young adults

Photo credit: Stefan Schmitz licensed under CC BY-ND 2.0

and their personal audio devices may be at least partially to blame. Melanie Campbell, a professor of Rehabilitation Medicine at the University of Alberta, warns that young adults “may be destined to swap out their headphones for hearing aids.” The problem is that this cohort “particularly loves music, they love it loud and they have very few worries about the future.” Campbell notes that World Health Organization statistics show that “[m]ore than one billion young adults are at risk of hearing loss,” and “[a]mong people aged 12-35 years, almost half are exposed to dangerously high levels of noise from personal audio devices like headphones while four out of 10 are exposed to unsafe levels of sound at concerts and other entertainment venues.”

According to Campbell, the primary cause for this hearing loss these days is noise-induced hearing loss (NIHL). What makes hearing loss particularly insidious, is that people generally don’t lose their hearing overnight. Instead, says Campbell, “[i]t creeps up and you gradually forget that you’re not hearing the door squeak, or you don’t hear people’s heels on the floor.”

To give young Canadians the information they need to protect their hearing and prevent hearing loss, Campbell has been promoting Sound Sense, a project led by the Hearing Foundation of Canada that spreads awareness about hearing loss in Canadian schools.

Spreading awareness about NIHL and how to prevent it is, of course, the the best option. Every school in the U.S. should regularly test students’ hearing and include information about NIHL in their health education programs. Given that NIHL is 100% preventable, the failure to educate children about how they can avoid NIHL is as insidious as the disorder.