Deafness
Deafness is the complete loss of hearing that affects millions of people worldwide. While most hearing loss is permanent and cannot be reversed, understanding its causes, recognizing its signs, and exploring available treatments can significantly improve quality of life and communication abilities.
Table of contents
- What is Deafness and Hearing Loss
- Global Impact and Scope
- Signs and Symptoms
- Causes of Deafness
- Types of Hearing Loss
- Diagnosis and Testing
- Treatment and Management Options
- The Deaf Community and Culture
- Living with Hearing Loss
- Prevention
What is Deafness and Hearing Loss
Deafness is the complete loss of your hearing[1]. A person who is not able to hear as well as someone with normal hearing — hearing thresholds of 20 decibels (dB) or better in both ears — is said to have hearing loss[1]. If you have partial hearing loss you are known as being “hard of hearing”[1].
People who are hard of hearing usually have hearing loss ranging from mild to severe. They usually communicate through spoken language and can benefit from hearing aids (devices that make sounds louder), cochlear implants (small electronic devices surgically inserted into the inner ear), and other assistive devices as well as captioning[1].
Deaf people mostly have profound hearing loss, which implies very little or no hearing. They can benefit from cochlear implants. Some of them use sign language for communication[1].
Global Impact and Scope
Hearing loss is a significant public health problem affecting close to 50 million people in the United States alone[14]. More than 1 in 10 people in the United States have some degree of hearing loss. An estimated 60,000 people have hearing loss in one ear. About 1 in 3 adults over 65 and nearly half adults 75 and older have age-related hearing loss. About 2 in 1,000 babies are born with some type of hearing loss[8].
Globally, over 5% of the world’s population — or 430 million people — require rehabilitation to address their disabling hearing loss, including 34 million children. It is estimated that by 2050 over 700 million people — or 1 in every 10 people — will have disabling hearing loss[1].
Disabling hearing loss refers to hearing loss greater than 35 decibels (dB) in the better hearing ear. Nearly 80% of people with disabling hearing loss live in low- and middle-income countries. The prevalence of hearing loss increases with age, among those older than 60 years, over 25% are affected by disabling hearing loss[1].
Unaddressed hearing loss poses an annual global cost of almost US$ 1 trillion. Over 1 billion young adults are at risk of permanent, avoidable hearing loss due to unsafe listening practices[1].
Signs and Symptoms
It’s not always easy to tell if you’re losing your hearing. Most people lose their hearing gradually. They may not even notice that it’s happening[8].
In general, you may be developing hearing loss if you often ask people to repeat themselves, have trouble following a conversation especially when you’re talking on the telephone or in a noisy environment like a restaurant, think people are mumbling, or can’t hear certain high-pitched sounds like birds singing. You may also need to turn up the volume on your television, computer or tablet, have tinnitus (ringing in your ears), feel earache, feel as if there’s pressure or fluid inside your ear, or have balance problems or dizziness[8].
If you are deaf, you may misunderstand conversation, not respond when spoken to, not react to loud noises, or have unclear speech. You may also hear noises in your ears, like ringing, hissing, or buzzing. This is known as tinnitus[3].
Signs in Babies and Children
Babies with hearing loss may seem to hear some sounds but not others. They may not startle to loud noises, not turn to the source of a sound after 6 months of age, not say single words like “mama” or “dada” by age 1, or not react when you say their name[8].
Older children with hearing loss may say “huh” a lot, be slower to learn to speak than other children their age, have unclear speech, not follow directions, or turn up the volume on television or tablets[8].
Causes of Deafness
Many things can cause hearing loss. For example, short-term or sudden exposure to very loud noise — like attending a loud concert — can affect your hearing[8].
Deafness can be caused by abnormal growth of the tiny bones in the middle ear, damage or malfunction of the cochlear (the spiral-shaped organ in your inner ear) in your inner ear, problems with the nerve between the cochlear and the brain, exposure to loud noise, or some medicines and medical conditions[3].
You may be born deaf, or you may lose your hearing over time. Losing your hearing over time is more common in people who work in noisy environments or have been exposed to loud machinery and tools. Losing your hearing is more common as you get older[3].
Causes During Different Life Periods
Individuals are most susceptible to hearing loss effects during critical periods in life[1]:
Prenatal period: Genetic factors including hereditary and non-hereditary hearing loss, and intrauterine infections such as rubella and cytomegalovirus infection can cause hearing loss[1].
Perinatal period: Birth asphyxia (a lack of oxygen at birth) can cause hearing loss[1].
Some diseases or circumstances that can cause deafness include chicken pox, cytomegalovirus, mumps, meningitis, sickle cell disease, syphilis, lyme disease, and diabetes. Studies have shown that people with diabetes are more likely to have some kind of hearing loss. A treatment for tuberculosis (TB) called streptomycin is believed to be a key risk factor. Hypothyroidism, arthritis, and some cancers can also cause hearing loss. Teenagers exposed to second-hand smoke may also be at risk[2].
The inner ear is home to some of the most delicate bones in the body, and damage to the eardrum or middle ear can cause hearing loss and deafness in a range of ways[2].
Types of Hearing Loss
There are three types of hearing loss[8]:
Conductive hearing loss: In this hearing loss, something keeps sound from passing through your outer ear (ear canal) or your middle ear. This type involves the outer or middle ear. Problems in the external auditory canal (outer ear), eardrum, or the bones of hearing (the middle ear) may cause a conductive loss. It can often be corrected by medication or surgery[6].
Sensorineural hearing loss: This hearing loss happens when something damages your inner ear over time. This type involves the inner ear. It may be damage to the cochlea (inner ear), auditory nerve, or the auditory centers of the brain. Rarely, sensorineural hearing loss happens very quickly. This is sudden sensorineural hearing loss (SSHL), or sudden deafness. SSHL may happen all at once or over a few days[8].
Mixed hearing loss: This happens when you have issues in your middle or outer ear (conductive hearing loss) and your inner ear (sensorineural hearing loss). It is a mix of the two types[5].
Diagnosis and Testing
Your doctor will ask you about your symptoms and examine your ears, check your overall health and medical history. They can also arrange for you to have a hearing test[3].
A basic hearing evaluation is likely to involve three steps: a review of the individual’s hearing and general health, including family history; a visual examination of the ear canal with an otoscope (a special magnifying light used for this purpose); and hearing testing, which may include a tone test during which the individual wears headphones and listens for short tones of different volumes and pitch that are played into the right and left ears separately, a pressure test which uses air pressure to determine the flexibility of the eardrum and tiny bones in the middle ear, and a speech test which involves listening to spoken words at different volumes and repeating them[20].
If you think your hearing is getting gradually worse or you’ve had treatment for an ear infection or earwax build-up but your hearing has not come back, see a doctor[15].
Treatment and Management Options
Although most hearing loss is permanent and cannot be reversed, it can be successfully addressed and managed to improve quality of life[20]. Hearing loss can’t be reversed, but surgery to treat some issues can improve hearing. Devices like hearing aids can reduce hearing loss[8].
Hearing Aids
Hearing aids can offer dramatic improvement for most people with hearing loss. If you have hearing loss but still have a good speech understanding score, a hearing aid can be used to amplify sound in your ear and improve overall hearing[6].
These devices are available in several styles depending on the severity of hearing loss, ranging from completely-in-the-canal hearing aids to behind-the-ear devices[16]. They make sounds louder and make them easier for the inner ear to pick up. They’re typically either analog or digital[17].
Cochlear Implants
When hearing aids are no longer beneficial, a cochlear implant can help restore hearing. Cochlear implants are unique, electronic devices. Unlike a hearing aid that only amplifies sound, an implant actually transmits an electrical signal directly to the inner ear (cochlea). After one of our skilled surgeons will implant the internal transmitter, and with regular listening therapy and practice, you can dramatically improve your hearing and comprehension[16].
Other Implantable Hearing Devices
In addition to cochlear implants, there are other implantable hearing devices that may help treat specific hearing loss. These implantable devices send sound vibrations to the inner ear and bypass damaged areas of the middle ear. Bone-anchored devices can be implanted directly under the skin or are transcutaneous[16].
Surgical Procedures
If your hearing loss is the cause of extensive damage to middle or outer ear, surgeons can perform procedures that reconstruct your ear for better hearing. These include ossicular chain reconstruction (replacing damaged middle ear bones using prosthetics), tympanoplasty (surgically closing a perforated eardrum), stapedotomy (for patients with otosclerosis), and aural atresia repair (for those born without an ear canal)[16].
Medical Treatments
There are some ear conditions that can be improved with medication alone. If you have frequent ear infections, antibiotic pills or drops are a standard treatment option. Steroids can also be used to treat inflammation or sudden hearing loss[16].
Early Intervention for Children
Hearing loss can affect a child’s ability to develop speech, language, and social skills. The earlier a child who is deaf or hard-of-hearing starts getting services, the more likely the child’s communication (speech or sign language) and social skills will reach their full potential. Babies who are diagnosed with hearing loss should begin to get intervention services as soon as possible, but no later than 6 months of age[11].
The Deaf Community and Culture
While some people see deafness as a problem, others see it as just another way of being. In Australia, there is a strong Deaf community with its own culture. Many deaf people find it offensive that deafness is seen as an abnormality and don’t seek “cures”[3].
The National Deaf Center is using the term deaf in an all-inclusive manner, to include people who may identify as deaf, deafblind, deafdisabled, hard of hearing, late-deafened, and hearing impaired. NDC recognizes that for many individuals, identity is fluid and can change over time or with setting[4].
American Sign Language
Sign languages are complex, natural languages, with their own grammar, vocabulary, and dialects. There is no universal sign language; countries and regions around the world have their own signed languages. While American Sign Language (ASL) is the most widely used sign language in the United States, other sign languages like Black American Sign Language (BASL) and Plains Indian Sign Language (PISL) reflect the rich linguistic variety within deaf communities[4].
In ASL, the shape, placement, and movement of the hands, as well as facial expressions and body movements, all play important parts in conveying information. ASL is not a communication code that merely represents English. It is its own distinct language[4].
Terminology to Avoid
Some common terms that are generally viewed as offensive within the deaf community include “hearing impaired,” “deaf-mute,” and “deaf and dumb.” These terms have some intrinsic problems, such as a deficit framing that assumes that deafness is negative. It is generally best to avoid these terms[4].
Living with Hearing Loss
If you are deaf, you may experience some barriers in society. You may choose to use hearing technology. You may also prefer to live without using hearing technology. Many people who are deaf experience deafness as a normal part of their life[3].
Communication Strategies
By practicing good communication skills, you and your family members can take steps to improve your listening experience. Wait until you are in the same room to talk with others. Ask your conversation partner to slow down their speech if you have difficulty following. Ask your conversation partner to face you when speaking—no backs turned or heads down looking at screens. Let the person speaking know if you are having trouble hearing or understanding (don’t pretend to understand). Use closed captioning when watching television or movies. Take some dedicated quiet time (listening breaks)[19].
If you have hearing loss, there are things you can do to help you communicate with others and avoid more damage to your hearing. Focus on visual cues, as body language, facial expressions, and gestures help the listener understand the meaning of a conversation. Choose the best listening location—for example, choose restaurants with good lighting to see the person’s lips more easily or meet in a room with carpet to reduce echo. Don’t be afraid to explain your hearing loss to others so they can make adjustments[21].
Maintaining Hearing Aids
Hearing aids require special care to ensure that they work properly. You should have a hearing aid cleaning brush and a user manual that can assist in performing routine maintenance. To keep your hearing aid in good working order, perform visual checks daily, check batteries regularly, clean the hearing aids regularly with a soft, dry cloth, and minimize moisture in the hearing aids[19].
Prevention
You can protect your hearing by reducing your exposure to loud noise or wearing suitable protection such as ear muffs or ear plugs[9]. The most common cause of acquired hearing loss is noise, which accounts for over one quarter of people affected by hearing loss[9].
WHO estimates that 50% of hearing loss can be prevented through public health measures[7]. In some cases, hearing loss is temporary. Unfortunately, it can also be permanent, especially if repeated loud noise causes damage to hair cells, membranes, nerves or other parts of your ear. If you’re experiencing hearing loss, it’s critical to implement protective strategies to prevent further damage[21].
Limit loud sounds. For most people, it’s impossible to avoid all loud noises. However, noise-induced hearing loss is a direct result of repeated exposure to loud sounds. Specifically, 85 dBA or above can cause hearing loss. Sirens, movie theaters, motorcycles and fireworks all fall at, or above, this level. Wear ear protection. If you know you’re going to be around loud sounds, like a concert or amusement park, wear ear protection. Earplugs and earmuffs can reduce noise by 15 to 30 decibels[21].
