Researchers are just beginning to understand the relationship between hearing loss and mental health. It was already well understood that hearing loss can cause social isolation, but researchers now have a great deal of evidence that it may also exacerbate or create mental health problems.
This article will examine the primary causes of hearing loss and the ways in which hearing loss can affect mental health.
How Hearing Loss Happens
Hearing loss can be described in terms of where the problem occurs within the hearing system. Two of the terms used are Conductive hearing loss and Sensorineural hearing Loss (SNHL).
Conductive hearing loss occurs when sound is cannot pass freely into the inner ear; and the problem is found in the outer or middle ear areas. Poor sound transmission may be due to a blockage caused by a buildup of wax or an ear infection. It may be also be caused by a congenital abnormality, injury or disease process which has created a physical blockage or deformity in the ear. Surgery or medications can sometimes be used to correct the problems causing conductive hearing loss.
Sensorineural Hearing Loss (SNHL) is used to describe hearing loss attributed to problems occurring within the inner ear and acoustic nerve pathways. The inner ear or cochlea contains nerve-endings which are responsible for translating incoming sound information into electrical signals. SNHL occurs is when these cochlear cells have been damaged or have died. Damage to the nerve pathways (or more specifically the spiral ganglion neurones (SGCs) that carry the electrical signal from the ear to brain also results in SNHL.
In some rare cases damage directly to the brain can also cause hearing loss.
There are many causes for hearing loss including:
- Congential birth defects which prevent the inner ear canal or cochlea from forming correctly
- Viruses and infections
- Diseases including Mitochondrial disease, Otosclerosis, mumps and Meniere’s disease
- Ototoxic medications including Aminoglycoside antibiotics, large doses of aspirin, certain diuretics and some chemotherapy drugs
- Presbycusis (Age-related hearing loss). This is a form of sensorineural hearing loss which becomes evident in ageing auditory systems.
- Physical trauma
- Exposure to very loud noises, either over a prolonged period or caused by one sudden event. Noise-exposure is also a form of sensorineural hearing loss.
More than 10 million people in the United Kingdom have a hearing impairment (Actiononhearingloss.org.uk, 2015).
70% of people aged 70 or older are estimated to have some degree of hearing loss.
Potential Mental Health Problems Relating to Hearing Loss
Research has found an increased risk of specific mental health problems occurring when a person has a hearing impairment, including:
- Anxiety disorders
Social Isolation – A Contributing Factor
Some of these mental health conditions are created or exacerbated by the social isolation that a person with a hearing impairment feels. If a hearing-impaired person cannot communicate effectively with other people, social interaction becomes difficult. This can lead to anger, frustration, depression, anxiety and cognitive decline.
A person with a hearing impairment may eventually stop even attempting to communicate with other people, worsening any mental health problems that they suffer from.
A study by The National Council on the Aging (NCOA) discovered that from 2,300 people over the age of 50, those with a hearing impairment were more likely to experience depression, anxiety and paranoia. They were also less likely to participate in social activities, which increases the social isolation they might feel.
An Italian study looking at the mental health of adults aged 35-54 who had hearing loss found a similar link to depression (D Monzani, 2008). They reported higher levels of psychological distress, anxiety, depression, hostility and interpersonal sensitivity in hearing-impaired people.
A John Hopkins study found that people with hearing loss were more 57% more likely to be depressed and were also 36% more like to have prolonged stretches of illness or injury than those without hearing loss (Hopkinsmedicine.org, 2015).
People with hearing loss commonly feel frustrated and angry at their inability to communicate well with other. Those feelings can contribute to depression if left unchecked.
Anxiety is typically described as a general feeling of nervousness or unease about an event. A person with hearing loss may experience more anxiety in social settings because of difficulties hearing and therefore understanding what people are saying.
When a person has impaired hearing, common tasks can become difficult – ordering food, hearing questions, hearing on a phone and hearing surrounding traffic. With more things to worry about, it is easy to understand why a hearing-impaired person could become anxious or paranoid.
Social isolation caused by impaired hearing can also increase a person’s anxiety.
Dementia refers to a broad category of brain diseases including Alzheimer’s disease, vascular dementia,
Lewy body dementia, and frontotemporal dementia. These diseases progress gradually and can affect a person’s cognition, memory, language skills and behaviour.
A 2011 study from John Hopkins University found that people with mild hearing loss are twice as likely to develop dementia. For people with moderate and severe hearing loss, there was a three-fold and five-fold increase in dementia risks were shown respectively (Hopkinsmedicine.org, 2015).
It is thought that dementia may be linked with hearing loss because people with hearing loss use their brain differently to decode sounds. Other theories include the fact that certain parts of the brain commonly affected by dementia are related to those used to decipher sound.
Impact on Memory and Thinking Skills
A study from Harvard University indicates that hearing loss may also be linked to a loss of memory and thinking skills (Howard LeWine, 2013). From a group of nearly 2,000 people over the age of 70, those with hearing loss were found to be more likely to develop cognitive impairment. A cognitive impairment may have an impact on overall mental health and increase the social isolation a person feels.
Most people don’t think about the potential ramifications that hearing loss has on mental health. To avoid these potential mental health issues, it is highly recommended that people have regular hearing checks and obtain help to address their hearing loss.
This post was written for Carewatch by Joan McKechnie, Audiologist, BSc Hons Audiology & Speech Pathology.