For most people, hearing loss is a condition that affects one aspect of life; the ability to hear. However, newly emerging evidence has found that there may be a connection between from hearing loss to dementia and cognitive decline.

The evidence 

  • People with untreated mild hearing loss are almost twice as likely to develop dementia than those with normal hearing; with moderate hearing loss, they are three times as likely; and those with severe hearing loss are up to five times more likely to develop dementia than those with normal hearing
  • A John Hopkins study concluded that adults with hearing loss developed cognitive impairment 3.2 years earlier than people without hearing loss. 
  • An article in the Lancet Commission concluded that 35% of dementia cases could potentially be prevented, with hearing loss listed as the most significant preventable risk factor for the condition

Establishing the link between hearing loss and cognitive decline

The link between hearing loss and cognitive decline is now accepted, but the reason why hearing loss can cause cognitive decline are not completely established. 

At present, there are several theories to consider. The first is the fact that people living with untreated hearing loss tend to be less socially active and engage in fewer conversations. As it is widely known that keeping the brain active is important when it comes to preventing dementia, this lack of social interaction – and thus brain stimulation through conversation – becomes problematic. 

The second theory is related to the lack of auditory stimulation that occurs due to hearing loss, which in turn causes sections of the brain to degenerate. 

It has also been suggested that a secondary health factor, potentially conditions such as vascular disease, may be responsible for both conditions – but this has yet to be confirmed. 

What we do know for sure, is that the link between dementia and hearing loss is well-established, and that research continues in the effort to establish why this is the case. 

Does this mean everyone with hearing loss will develop cognitive decline? 

Not at all. The studies that have found a link between dementia and hearing loss focus primarily on untreated hearing loss; i.e. individuals who are living with hearing loss but are not using hearing aids. Using hearing aids can reduce the risk of dementia – so there is absolutely no suggestion that simply anyone who is diagnosed with hearing loss will experience cognitive decline due to the condition. 

Treatment, however, can only be accessed following a diagnosis; and unfortunately, hearing loss can be difficult to diagnose. When the condition first develops, it can be almost impossible to notice – the brain simply adapts to the lack of sound, and people do not notice its absence. In fact, it can take up to 10 years for people to seek treatment for hearing loss, and it’s estimated that up to 85% of people with hearing loss are untreated. 

By far the best way to overcome this issue and ensure early detection of hearing loss is to attend regular hearing tests with an audiologist. Regular testing allows you to monitor your hearing over a period and makes it more likely that, should hearing loss develop, it will be noticed – and treated – as soon as possible.