Medical and scientific news

Noise exposure leads to hyperglycemia

Photo credit: PhotoMIX Company from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

This report from Diabetes Control discusses a newly published research paper showing that noise exposure was associated with the development of hyperglycemia. Diabetes Control notes that the study is only correlational and does not establish causality.

I have several issues with the paper, starting with the fact that the research was done in 2012 and only analyzed and published now. Occupational noise exposure was also strongly correlated with educational attainment and smoking, so it is possible that those factors and not noise exposure itself was the cause of the hyperglycemia.

But the results are consistent with prior studies done over the last two decades showing correlations between noise exposure and obesity and hyperglycemia in non-occupational settings.

Each similar report is like another tile in a mosaic, providing additional insight into the broader picture of the hazards of noise exposure.

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.

Could a drug being developed to prevent hearing loss help fight COVID-19?

Photo credit: Martin Lopez from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

As those who follow my writings know, I’m a big believer in the old public health principle that prevention of disease is almost always better and cheaper than treating it. That principle applies to hearing loss. Preserved normal hearing is much better than the best hearing aid, and costs almost nothing–just avoid loud noise or use hearing protection.

But we follow developments in treating or preventing hearing loss caused by noise exposure. The Holy Grail for this research is a drug that people could take after noise exposure, to prevent any lasting auditory consequences. One of these drugs under development is called Ebsalen.

This new report in the peer-reviewed online journal ScienceAdvances discusses repurposing Ebsalen to fight COVID-19 infection.

We think that may be a better use of Ebsalen than its originally intended use.

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.

 

 

 

 

How noise affects our brains

Image credit: Pete Linforth from Pixabay

by Daniel Fink, MD, Chair, The Quiet Coalition

Everyone acquires information by different means. Some people talk to friends, some people do an internet search, some read newspapers or magazines, and these days many listen to podcasts.

I am too impatient to listen to podcasts–I can read much faster than anyone can talk–and I have hyperacusis, so I don’t listen to podcasts on my smartphone while walking around. I prefer to obtain information by reading.

But from time to time I make an exception, and this wonderful podcast is one of those exceptions.

On his “This Is Your Brain” podcast, Dr. Phil Steig interviews our friend Mathias Basner, MD, PhD, MSc, Professor of Psychiatry at the University of Pennsylvania and Director of the Behavioral Regulation and Health Section. Dr. Basner is one of the world’s experts on the effects of noise on sleep and human health, and in this podcast he shares his knowledge about the effects of noise on hearing and the brain.

I listened on my computer. It’s only 19 minutes long, and well worth your time.

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.

Age-related hearing loss is almost certainly noise induced

Photo credit: Andrea Piacquadio from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

Hearing loss in old age is often called age-related hearing loss or presbycusis. This implies that hearing loss is part of normal aging, just like the need for bifocals called presbyopia. This article in the Society for Neuroscience’s journal reports that what is commonly called age-related hearing loss is really hair cell loss, indicative of auditory damage caused by noise

That was my conclusion based on a literature review, presented at the 12th Congress of the International Commission on the Biological Effects of Noise in Zurich in 2017.

Another recent report, this time in The Conversation, discusses research in fruit flies that may shed light on what the author calls age-related hearing loss. I don’t know how much noise fruit flies are exposed to–laboratory facilities are not quiet–but I suspect that the effects of whatever molecular changes occur in human ears with aging are compounded by cumulative noise exposure over one’s lifetime

Our ears are like our eye and our knees–we only have two of each. We don’t stare into the sun. We wear sunglasses when outdoors in bright light. In fact, sun exposure causes cataracts. We try not to injure our knees, although these can be surgically replaced.

And we need to protect our ears so they last us a lifetime.

Avoiding noise-induced hearing loss is simple: avoid exposure to loud noise, and if one can’t avoid that, use hearing protection.

Because if a noise 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.

Chemical earmuffs to prevent hearing loss?

Photo credit: Ben Dracup licensed under CC BY 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

Perhaps I shouldn’t be surprised when researchers try to develop a more complicated way of doing something that can already be done much more easily and much more cheaply. This article in The Hearing Journal reports research on chemicals that appear to prevent noise-induced hearing loss in an experimental animal model. The hope is that in the future chemicals can be developed that when taken by humans will prevent hearing loss after noise exposure.

Such a chemical might be helpful for those who can’t avoid loud noise, e.g., soldiers or police officers, or perhaps for those inadvertently exposed to loud noise.

For the rest of us, that may or may not ever come to fruition. But a much easier and cheaper way to prevent noise-induced hearing loss already exists. What is it? Simply this: Avoid exposure to loud noise, and if that can’t be done, use hearing protection like earplugs or earmuffs!

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.

Could noise be a risk factor for hypertension?

Photo credit: Kateryna Babaieva from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

Could noise be a risk factor for hypertension? This fascinating study from Chengdu, China, suggests that the answer is yes. The study design is innovative. The investigators measured bilateral high frequency hearing loss (BHFHL) and blood pressure in 21,000 workers, with an average age of 40. Hearing loss was a proxy measure for occupational noise exposure. Workers with greater hearing loss, as measured by audiometric tests, had a greater risk of also having high blood pressure.

The study is an exploratory one, and it is cross-sectional, i.e., the workers were not followed for decades and the study is based on one-time measurements of hearing and blood pressure. Other factors known to be associated with hypertension, such as weight and alcohol consumption, were not documented. And only a proxy measure of occupational noise exposure, bilateral high frequency hearing loss, was used, rather than actual noise measurements in the workplace. But the number of workers studied was large enough to provide high statistical significance, and the results were striking. As the researchers noted, “subjects having mild and high BHFHL had a higher hypertension risk of 34% and 281%, respectively (both P<0.001). Dose-response relationship between BHFHL and hypertension was found in both males and females.”

Studies done in the U.S. also show a correlation between occupational noise exposure and hypertension. The Chinese study may show a stronger relationship between occupational noise exposure and hypertension because workplace protections and their enforcement may be less stringent in China than in the U.S.

What are the implications of this study for public health? More than 100 million Americans have high blood pressure. At least two studies show that noise exposure in everyday life is great enough to cause hearing loss. Is it also great enough to contribute to the epidemic of hypertension in the U.S.?

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 the increased risk of serious stroke

Photo credit: Aleksandar Pasaric from Pexels

by Daniel Fink, MD, Chair, The Quiet Coalition

This report in Science Daily describes a fascinating study done in Barcelona. The study found that patients who lived in noisy areas suffered worse strokes than those who didn’t. Patients who lived in quieter areas near green zones, on the other hand, had less severe strokes.

Only this report and the abstract, published in Environmental Research, are available outside a pay wall, so I can’t comment on the scientific methods used in the study, but Environmental Research is a well regarded, peer-reviewed scientific journal. And the study results are consistent with past experience.

Hypertension is a well-known risk factor for stroke, with higher blood pressures being associated with more severe strokes. The Barcelona report supports other studies, including human, animal, and epidemiology studies, showing that noise exposure increases blood pressure due to autonomic nervous system and hormonal stress responses to noise. I suspect that is the likely explanation for the new study’s findings.

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 disrupts sleep. Could this be linked to Alzheimer’s?

Photo credit: Alyssa L. Miller licensed under CC BY 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

The most common definition of noise is “noise is unwanted sound.” We at The Quiet Coalition recently came up with a new definition: noise is unwanted and/or harmful sound. The specific evidence-based sound levels associated with adverse health and public health hazards are summarized in my article in Acoustics Today, “Ambient Noise Is ‘The New Secondhand Smoke.'”

Sounds as low as 30-35 A-weighted decibels* can disrupt sleep. Uninterrupted sleep is important for both daily function and health. Nighttime noise is increasing, caused by aircraft noise, road traffic noise, emergency vehicle sirens, horn-based alerts, and sounds from clubs, bars, and concerts, with the specific noise source(s) depending on where people live.

It has been known since 2013 that sleep is necessary for cellular cleaning functions in the brain. A new study, reported by NPR, extends this research to Alzheimer’s disease. It has been known for some time that poor sleep is associated with Alzheimer’s disease, and patients with Alzheimer’s disease don’t sleep well. The new study shows that there are waves of cerebrospinal fluid occurring every 20 seconds during sleep, preceded by electrical activity. The electrical waves appear as slow waves on an EEG. Those with Alzheimer’s disease have fewer slow waves on their EEGs.

I have only read the NPR report, not the underlying article in Science, and I’m not 100% sure the cause-effect relationship between sleep disruption and Alzheimer’s has been clearly established. Which really came first, the sleep problems or the Alzheimer’s disease? Nonetheless, the study underscores the importance of a good night’s sleep.

Noise pollution is a public health problem. And one wonders if the increase in Alzheimer’s disease is due in part to increased nighttime noise levels.

*A-weighting adjusts sound measurements to reflect the frequencies 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 treatment for tinnitus

Photo credit: Dr. Craig Hacking and Prof Frank Gaillard licensed under CC BY-SA 4.0

by Daniel Fink, MD, Chair, The Quiet Coalition

This report from the University of California San Francisco discusses a Phase 1 trial of deep brain stimulation for tinnitus. A Phase 1 trial is a preliminary trial to see how a new treatment works. Then there are Phase 2 and Phase 3 trials.

Most treatments do not pass all the hurdles to be approved for regular use. And deep brain stimulation is expensive and risky.

By comparison, prevention of most forms of tinnitus is cheap, easy, and safe: avoid head trauma and noise exposure and one is unlikely to develop tinnitus.

That sounds like a much better idea than deep brain stimulation to me.

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.

Venture money surges into hearing health treatments

by David M. Sykes, Vice Chair, The Quiet Coalition

I’ve been watching Dr. Charles Liberman’s company, Frequency Therapeutics, for several years. He’s the physician-researcher who runs Harvard’s Lauer Tinnitus Research Center in Boston and who has published papers starting in 2009 about “hidden hearing loss,” papers that broke open the Congressional log-jam that prevented significant funding going into hearing disorders. His company has raised an eye-popping $228 million in venture capital–that’s a LOT for an early-stage company–and now they’ve gotten approval from the Food and Drug Administration to fast-track trials of their first product.

But Frequency Therapeutics isn’t the only company in this space. I recently saw information at an investor conference showing that another half dozen companies have also raised significant amounts of venture capital for hearing-disorder treatments. Collectively, they’ve raised over a quarter of a billion dollars! That’s extraordinary progress for a long overlooked sector where nothing seemed to happen for decades and where the only treatment option for decades were extraordinarily expensive hearing aids from a handful of powerful companies charging inflated prices no one could afford.

Now there’s an active market and venture capitalists are diving in! That is a real sign of progress!

Thanks are due to the President’s Council of Advisers on Science and Technology that in 2016 published a report on the noise-induced hearing loss market, and to the National Academy of Medicine report on hearing loss in America that issued a few months later. Those two reports also led to the bi-partisan Warren-Grassley OTC Hearing Aid Act that President Trump signed into law in 2018 and that goes in to effect in January 2020. That act, in turn, has created a surge of investment in personal sound amplification products, or PSAPs, which are high-tech ‘hearing aids’ you’ll soon be able to buy from your local drug store for 1/10th the price of conventional hearing aids.

Change is here!

David Sykes chairs several professional organizations in acoustical science: QCI Healthcare Acoustics Project, ANSI Committee S12-WG44, the Rothschild Foundation Task Force on Acoustics, and the FGI Acoustics Committee. He is lead author of “Sound & Vibration 2.0” (Springer, 2012), a contributor to the NAE’s “Technology for a Quieter America” and the GSA’s “Sound Matters,” and co-founded the Laboratory for Advanced Research in Acoustics at Rensselaer Polytech. A graduate of UC-Berkeley with advanced degrees from Cornell, he is a frequent organizer of professional conferences in the U.S., Europe, Asia and the Middle East.