Does Hearing Loss really cause dementia?

Dementia Awareness week is an annual campaign in May organized by the Alzheimer's Society to raise awareness about dementia and encourage action on the issue. The 2025 campaign gives focus on dementia diagnosis and the importance of early detection.

For many years there have been reports across media outlets and in some advertising about the “link” between cognitive decline and untreated hearing loss, citing research studies and often appearing highly credible and science based. These reports often give the impression that untreated hearing loss directly causes or contributes towards cognitive decline, and that hearing aids can therefore help to prevent onset.

Direct quotes from examples include: “Hearing loss is to blame for a third of dementia cases in older people” or “Hearing aids have been shown to reduce the risk of dementia to the level of a person with normal hearing”. These reports are certainly attention grabbing and appear to offer hope. Anybody who has experienced the often cruel and devastating impact of cognitive decline would understandably be drawn to such articles and advertising, with the very prospect of even a partial “cure” holding huge appeal.

At Optimal hearing we recently attended a lecture on this topic by Kevin Munro, Professor of Audiology and director of the Centre for Audiology and Deafness at the University of Manchester. As former chairman of the British Society of Audiology, he is an expert in the field and has recently been working to provide guidance for professionals on this specific subject.

It does seem logical that the stimulation to the brain provided by hearing aids would help someone with hearing loss to maintain normal cognitive function, however things may not be quite this simple. Given how emotive the topic is, and given the frequent media headlines and reports, we would like to share the broad headlines and messages to put this into some context.

Why the confusion?

Partly because of terminology. When looking at predicting the likelihood of a disease or condition, it is often helpful to look at what are called “risk factors”. In this context, a risk factor is a variable associated with an increased likelihood of disease or infection. Research has shown that someone with hearing loss is at a higher probability of being affected by cognitive decline. Similar correlations also correspond to cholesterol, diabetes, blood pressure and level of physical exercise. However (and this is the important bit), correlation doesn’t necessarily mean causation. Whilst conditions tend to go together, it doesn’t mean that untreated hearing loss actually causes cognitive decline.

There is also overlap in the way they present. Observing someone having difficulty keeping up with conversations, slowness of response, misunderstanding or making strange or irrelevant responses may well be symptoms of untreated hearing loss, cognitive decline or someone who suffers both.

So what do we know?

Untreated (or poorly corrected) hearing loss is well understood to affect mood, increase mental fatigue, reduce short term memory and increase risk of falls. It can strain relationships and lead to social isolation, loneliness, depression and anxiety. Correctly fitted and consistently worn hearing aid can be of huge benefit and make a massive difference.

Current understanding is therefore best summarised that, for some people at high risk of cognitive decline, hearing aids may slow the process, but with the current studies and research completed at this point it is not conclusive. There are loads of benefits of wearing correctly prescribed and beautifully fitted hearing aids, but when it comes to hearing loss causing cognitive decline there is more research needed, and at this point there is no definitive evidence available which proves this to be the case.

(Information as of May 2025)