Incidence of hearing loss in Australia
The incidence of hearing loss in Australia is steadily rising, with one in six Australians directly affected by hearing loss. It is predicted that by 2050, this figure will increase to one in four people[1]. The incidence of hearing loss increases with age.
- 49.5% of people of working age (15 to 64) have a hearing impairment.
- 74% of people over 70 have a hearing impairment. Males are more likely to have a hearing impairment than females[1].
Possible signs of hearing loss
How the ear works
Sound waves are vibrations through the air. When we hear a sound (e.g. somebody’s voice), sound travels along the ear canal and causes the eardrum to vibrate (see image on the next page).
The vibration of the eardrum causes movement of the three bones in the middle ear. These bones move against the cochlea (the hearing organ) and pass the vibrations to thousands of special hair cells inside it.
The hair cells then send the sound as an electrical signal along the nerve to the brain, where we perceive the sound (our brain interprets the signal as sound).
Problems can occur in any part of the ear and may lead to temporary or permanent hearing loss. For some people the hearing loss is present from birth which is called a congenital hearing loss. For others it can be caused by problems arising throughout their lifetime or simply due to the aging process.
Degree of Hearing Loss
- Mild: Easy communication in most situations, with some difficulty in noisy environments, hearing over a distance, or if the speaker is looking away. A hearing aid may be of benefit.
- Moderate: Easy communication only in quiet, face to face situations. Some difficulties on the phone, listening to TV, in noise or over distance. Will usually benefit from hearing aids.
- Severe and Profound: Significant difficulty communicating in all environments, and nearly always relying on hearing aids or assistive listening devices. Sometimes hearing aids and Cochlear Implants improve communication.
Types of Hearing Loss
- Sensorineural hearing loss: caused by a loss of sensitivity of the hearing organ (the cochlea) or the hearing nerve. Sensorineural hearing loss is usually permanent. Sensorineural hearing loss is common in ageing or older people. It may also be caused by some infections or viruses, by diseases such as Meniere’s disease, by head injuries or exposure to loud noise (often workplace noise). In some people it is present from birth. People with sensorineural hearing loss often find hearing aids useful.
- Conductive hearing loss: Conductive hearing loss is caused by a problem in the middle or outer parts of the ear. It may sometimes be corrected by medical or surgical treatment. It can result from middle ear infection, blockage or fluid build-up in the middle ear. Other causes include malformations of the middle or external ear, diseases such as otosclerosis, injuries, perforations of the eardrum, or even a plug of wax in the ear canal. People with conductive hearing loss that cannot be treated medically may benefit from hearing aids.
- Mixed hearing loss: Mixed hearing loss is a combination of conductive and sensorineural hearing losses. This means there is damage to the cochlea or hearing nerves, as well as trouble in the middle or outer parts of the ear. This may be caused by a single disorder, such as otosclerosis, or a combination of two unrelated problems.
Hearing Assessments
If you have noticed that you or a friend is having difficulty hearing, a hearing assessment with an audiologist may be needed. A hearing test can be performed at any private or community clinic (a list of providers can be found at www.audiology.asn.au).
You will need a referral from your GP if you wish to be seen at a public hospital. If you have noticed a sudden change in your hearing, please present to a hospital emergency department immediately.
