Dementia is a progressive condition that affects the brain. Hearing loss may increase a person’s risk of developing dementia, partly through reduced social interaction. Wearing a hearing aid may help slow or prevent cognitive decline.
According to a 2016 study, almost one-quarter of people in the United States aged 12 years and older have some form of hearing loss. People aged 80 years and older are likely to have more advanced hearing loss.
Hearing loss may contribute to social isolation, lower quality of life, disability, depression, and dementia.
This article explores the link between dementia and hearing loss. It also discusses the risk factors for both conditions and how to manage them.
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Alzheimer’s disease, the most common type of dementia, is more common in people aged 65 years and over. In the U.S., about 1 in 10 people in this age group are living with the condition.
A 2018 study that followed 3,777 participants for 25 years found a link between hearing loss and a higher risk of developing dementia.
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Physical changes in the ear and brain cortex underpin the conditions
Similar physical changes in the ear and the brain cortex suggest a connection between hearing loss and dementia.
In vascular dementia, damage to blood vessels may also damage auditory apparatus.
Impaired social interaction may affect brain function
People with hearing loss receive degraded auditory input from their environment. When socializing, they may miss out on verbal and emotional information, which is crucial in social interaction. The loss of this vital information may directly impair brain structure and function.
According to the authors, reduced social interactions are as much of a risk factor for dementia as smoking and inactivity.
Hearing loss puts a cognitive burden on other processes
Someone with hearing loss may use more of their cognitive resources or energy to make sense of what they hear. This reduces the resources available for other cognitive processes, such as memory, language processing, and attention.
The effort of trying to make sense of speech, particularly in noisy environments, may lead to a decline in other brain functions, which is characteristic of people with dementia.
Hearing loss causes brain changes, and dementia-related brain changes cause hearing loss
The fourth mechanism that the researchers propose relates to changes in the brain’s medial temporal lobe (MTL).
People with Alzheimer’s disease have abnormal accumulations of a protein called tau that
People with hearing loss also display changes in MTL neurons, suggesting a relationship between the two conditions. The researchers suggest that in people with hearing loss, limited auditory input leads to overactivity in the MTL, which may cause or contribute to neurofibrillary tangles and beta-amyloid plaques.
They also suggest a two-way relationship, meaning that hearing loss may exacerbate changes that lead to Alzheimer’s disease, while the disease may cause changes that worsen hearing loss.
The researchers conclude that more research is necessary to clarify the processes that connect hearing loss and dementia.
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At the start of the study, every participant was aged 65 years or over, and researchers followed up with them over 25 years. The study found a link between self-reported hearing loss and cognitive decline. However, people who used hearing aids did not show a significant cognitive decline, suggesting that using hearing aids may have a protective effect.
Various factors can increase a person’s likelihood of developing dementia. These
- high blood pressure
- smoking
- depression
- obesity
- inactivity
- diabetes
- lack of social contact
- excessive alcohol consumption
- air pollution
- brain injury
- hearing loss
- being aged 65 years or older
Taking steps to reduce or eliminate these risk factors, where possible, may lower a person’s risk of developing dementia.
Preventing dementia
A 2020 report in
Other recommendations to help prevent dementia include:
- staying active socially, physically, and cognitively
- avoiding tobacco
- drinking alcohol in moderation or not at all
- maintaining a healthy weight and blood pressure
- avoiding air pollution, including secondhand tobacco smoke
According to the authors of the report, these steps could prevent or delay 40% of dementia cases.
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- loud noise
- earwax or fluid buildup
- punctured eardrum
- diabetes
- high blood pressure
- heart conditions
- stroke
- brain injury
- ototoxic medications, which doctors sometimes prescribe to treat cancer and heart disease
- family history of hearing loss
Preventing hearing loss
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- turning down the volume on the television, radio, or headphones
- avoiding putting objects in the ear, such as cotton-tipped swabs
- asking a doctor about treatments to soften earwax
- telling a doctor about any hearing-related changes while taking medications
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The following strategies may also help people with hearing loss and dementia:
- undergoing speech and language therapy
- using cue cards to remind people to speak slowly
- asking others to look directly at them while talking
- changing hearing aid batteries regularly
finding quieter places to talk or listen
Below are the answers to some common questions about hearing loss and dementia.
Does hearing loss precede dementia?
Hearing loss can precede dementia but not for everyone. A
Does hearing loss affect your memory?
Hearing loss may affect a person’s memory, as it places an
Hearing loss and dementia are both more common in older age, and research has shown that the two conditions are connected.
Although the exact processes are unclear, research suggests that the extra burden involved in interpreting auditory information causes changes in the brain that are characteristic of dementia.
People with hearing loss can use a hearing aid to reduce their risk of developing dementia.
People can also take preventive steps to avoid hearing loss, such as avoiding loud environments and telling a doctor about any changes in their hearing.