The link between hearing loss and Alzheimer’s disease

Today marks World Alzheimer’s Day, where health organisations across the world come together to raise awareness of dementia and Alzheimer’s, in the hope of one day defeating it once and for all. Here at Cirrus Research, our mission is to fight excessive noise levels, which are known to cause serious health conditions like tinnitus, hyperacusis and mental health illnesses. What many people may not know is that there is a clear link between hearing loss and Alzheimer’s disease, which for all those concerned with noise measurement and monitoring, is incredibly concerning. In this article, we look at Alzheimer’s, what the link between hearing loss and Alzheimer’s is, and what steps people can take in order to reduce the risk at home, in the workplace or out in the environment.

Alzheimer’s disease is a form of dementia that affects people’s memory, their ability to think, and their behaviour. Most commonly, these symptoms deteriorate over time eventually impacting every aspect of a person’s everyday life. Alzheimer’s is recognised as the most common cause of dementia, with the disease accounting for between 60 and 80 per cent of all dementia cases (https://www.alz.org/alzheimers-dementia/what-is-alzheimers).

Many people assume that developing dementia forms a natural part of the ageing process, but this simply isn’t the case, Whilst those of a more advanced age are more likely to develop the condition, as the video above demonstrates it can affect people much younger than one would usually expect. In the United States, roughly 200,000 under 65s suffer from early-onset Alzheimer’s, with their symptoms only ever deteriorating as they get older.

According to the NHS UK website, Alzheimer’s is caused by an abnormal build-up of proteins in around cells in the brain. Although many academics are unsure of what exactly causes this build up, what they are very sure of, is that these changes begin to occur many years before the first symptoms manifest themselves.

Both the Alzheimer’s Society and the UK National Health Service have published articles that discuss the link between hearing loss and Alzheimer’s disease. Unfortunately, there doesn’t appear to be any concrete scientific evidence to explain why or how hearing loss contributes to the risk of developing of Alzheimer’s. Currently, studies only show that those with hearing issues were more likely to develop dementia:

One theory as to how hearing loss may cause Alzheimer’s is explained by Dr Clare Walton, in that when someone suffers from hearing loss, their brain diverts crucial resources from other areas in order to fully process and understand sound and noise. It could be deduced from this that these diversions could lead to weakened brain function in other areas, making it more susceptible to damage, in turn potentially leading to dementia. Another aspect to consider is the feeling of isolation and depression that hearing loss can cause. It’s already fully accepted that hearing loss can cause depression and other mental health conditions (and sadly in some extreme cases, even suicide); could this be a factor in fully understanding the link between hearing loss and Alzheimer’s disease?

The long-term study that discovered this link was presented to the European Parliament on World Hearing Day, the coverage of which you can see below:

With an increase in the awareness of the link between hearing loss and dementia, including a motion put forward in the UK House of Commons by MP Norman Lamb, it’s with with great optimism that we may begin to see progress being made in the fight against excessive noise exposure, and a reduction in the number of people being unnecessarily put in harm’s way, by being provided with adequate hearing protection.