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.