Is There a Link Between Hearing Loss and Cognitive Decline?

On first inspection, hearing loss and cognitive decline – which includes conditions such as dementia and Alzheimer's disease – do not seem to have much in common. They are separate conditions that are dealt with by separate medical professionals, have different symptoms and affect different parts of the body. 

However, more and more studies are confirming that there does appear to be a link between the two, and that those with hearing loss seem to be at higher risk of dementia. This increased risk can be significant; one study found that those with moderate hearing loss were three times as likely to experience cognitive decline when compared to people without hearing loss. 

Why does this link exist?

There has yet to be a definitive answer to the question of why hearing loss and cognitive decline appear to be linked, but several theories have been presented, such as: 

• Changes in the brain due to age are common; this is often referred to as brain shrinkage. However, people with hearing loss seem to experience more significant physical changes in the brain; it is believed that this happens due to the lack of auditory stimulation. This increased shrinkage could contribute to higher rates of dementia.
• Mental activity is also important for cognitive health, but people who have hearing loss can become socially withdrawn and isolated, which can lead to lower mental activity levels and thus subsequent cognitive decline.
• It has also been suggested that living with hearing loss places extra stress on the brain, especially if the hearing loss is untreated. Due to this, the brain has less energy available for other cognitive functions, such as memory. 

However, it is important to note that while the exact reason for hearing loss/dementia link is not yet established, the fact that such a link exists is still an evidenced, accepted medical fact.

Does this mean anyone with hearing loss will develop dementia? 

No – an increased risk factor is not a guarantee; it is, instead, something that should be noted and acted upon as is appropriate. 

Hearing aids have been shown to be very effective at treating hearing loss. By restoring hearing function, many of the potential reasons that hearing loss has been so heavily linked with dementia can be assuaged; hearing aids can allow people to be more socially interactive and should also reduce the extra stress on the brain. There is also a significant quality of life factor to consider; hearing aids improve personal relationships and even increase earning potential. Increased usage of hearing aids could thus have an important role to play in mitigating the increased risk of developing amongst those with hearing loss. 

Of course, to obtain hearing aids, hearing loss must first be detected and diagnosed – which is not necessarily as straightforward as it may initially seem. Hearing loss can go undetected for many years, so visiting a hearing health professional for regular hearing tests is necessary in order to ensure that hearing loss can be identified as soon as it develops.