Dementia & Hearing Loss: What’s all the Fuss?

Dementia is a condition that affects the brain. It encompasses a collection of symptoms, including: memory loss, behaviour changes, altered thinking, impaired problem-solving, and eventually leads to difficulties completing everyday tasks. Put simply, dementia is not a specific disease that affects any two people the same way.

Dementia is very common. Recent statistics show it impacts 1 in 10 people over the age of 65, with the most common type of dementia being Alzheimer’s Disease.

In recent years, there has been growing speculation and talk among health professionals about the links between dementia and hearing loss. This has sparked the need for Audiologists to play more of a vital role in early intervention and dementia prevention.

In 2020, the Lancet Commission released a report on the 12 modifiable risk factors for dementia prevention, which was found to account for 40% of worldwide dementias. These included:

less education,
hypertension,
hearing impairment,
smoking,
obesity,
depression,
physical inactivity,
diabetes,
low social contact,
excessive alcohol consumption,
traumatic brain injury and
air pollution.

Dementia and hearing loss, so what’s all the fuss?

An interesting finding to come from this research was that out of all the above factors, untreated hearing loss was the #1 modifiable risk factor.

There are several theories why the link exists between dementia and hearing loss. One well-researched explanation is that hearing loss causes increased “brain strain” when having to fill in the gaps of what is not being heard. This takes a toll on the brain and thus depletes memory and thinking systems. The second is that hearing loss causes accelerated “brain atrophy” (loss of brain volume), with several neuroimaging studies showing similar patterns of brain atrophy among people who have an untreated hearing loss and Alzheimer’s Disease. The last explanation comes down to a loss of social connections and isolation as a result of hearing loss, wherein the brain is less engaged and “de-activates” itself. This comes back to the famous saying, “use it or lose it”.

We are commonly asked if hearing aids can help reduce dementia risk. In an exert from their report, the Lancet Commission stated, “[we need to] encourage the use of hearing aids for hearing loss and reduce hearing loss by protection of ears from excessive noise exposure”. Through hearing aids, we can re-stimulate the hearing pathways up to the brain to prevent auditory deprivation and reduce accelerated cognitive decline.

To learn more about the other modifiable risk factors for dementia prevention, click here.

References: