Hearing is one of our most important senses. It is central to our ability to communicate and engage with others. Regardless of age or stage, hearing loss has serious implications for our quality of life and ability to function. As stated in the recent WHO Report on Hearing, 2021 “Any decline in hearing capacity at any point during the life course, if not addressed in a timely manner, can adversely affect day-to-day functioning.”

Risk Factors for Dementia

In recent years, more and more research has come to light confirming the link between dementia and hearing loss. According to the updated Lancet Commission 2020 Report, Dementia Prevention, Intervention and Care, there are several risk factors for dementia:

• Hearing impairment
• Hypertension
• Smoking
• Obesity
• Depression
• Physical inactivity
• Limited education
• Diabetes
• Low social contact 
• Head injuries in mid-life
• Excessive alcohol consumption in mid-life
• Exposure to air pollution later in life

Note that at the top of this list is hearing impairment.

In Australia, hearing loss affects 74% of people aged over 70. It is estimated that people with severe hearing loss are five times more likely to develop dementia. Hearing loss is the largest potentially modifiable risk factor for age-related dementia. ( WHO Report on Hearing, 2021)

When other risk factors are also present, there is an even higher risk of dementia. For example, hearing loss and diabetes increase the risk. 

How are hearing loss and dementia linked?

There are a number of reasons that hearing loss can lead to dementia.

Age-related hearing loss is believed to lead to reduced auditory nerve responses. This in turn is associated with slower processing speed and brain structural changes. (Delano, 2021)

It is also believed that hearing loss may increase cognitive load, resulting in cognitive impairment on neuropsychological testing. (Strutt, 2021)

Hearing loss is also associated with higher levels of ß-amyloid, a key biomarker for Alzheimer’s disease. (Mun et al 2020)

Hearing loss contributes to both social isolation and loneliness at all ages, more specifically in women and older adults possibly because of decreased participation in activities, or by having a smaller social network. Social isolation is one of the risk factors for dementia.

What can be done to minimise the impact of hearing loss?

1. Prevention is better than cure. We need more education in the community about how to care for our hearing throughout our lives, so we aren’t adding to the probability of hearing loss as we age.
2. Adult hearing screening and early intervention become even more important given the links between hearing loss and dementia.
3. Hearing devices have a positive impact on an individual’s cognition. Treatment of hearing loss with hearing aids, cochlear implants and middle ear implants may delay cognitive decline. Encouraging older adults to use hearing aids if they are needed can also protect against cognitive decline and dementia. Sometimes hearing aids will be sitting in a drawer rather than in the ears of the owner. Uncovering reasons why they are not being worn, and finding solutions to these
4. Rehabilitative therapy is useful to enhance perceptive skills and develop communication and linguistic abilities. Music therapy is one area currently being researched to examine its impact on communication, movements, social participation and cognitive abilities in older adults. (Grenier et al, 2021)
5. The use of hearing assistive technology, and services such as frequency modulation and loop systems, alerting devices, telecommunication devices, captioning services and sign language interpretation, can further improve access to communication and education for people with hearing loss (Laureyns, 2021)

With the recent release of the Royal Commission into Aged Care Quality and Service, now more than ever, we need to support our community to age with grace and ensure the humane care of our elders. This includes finding ways to reduce the incidence and impact of dementia. Hearing loss is a risk factor we can minimise.