Hearing Loss Causes
About 466 million people in the world have disabling hearing loss.
How does this happen?
Hearing loss occurs when damage is done to the nerves coming from the ears, and this can be from one or more parts of the ear or the brain segment responsible for hearing.
Hearing loss can either be partial or total. This means that the person may be able to hear with one of the ears, hear muffled sounds, or may not be able to hear at all.
Hearing loss can also be permanent or temporal, depending on the cause.
Hearing loss affects people of all ages and can either be from birth or developed later in life.
Types of Hearing Loss
As stated earlier, hearing loss can vary in intensity and can be either temporary or permanent based on the cause.
Below are the types of hearing loss.
1. Sensorineural Hearing Loss
This is a hearing loss that occurs due to damage to the sensory hair cells in the cochlea or inner ear; this damage affects the transmission of impulses along the hearing nerve.
People with sensorineural hearing loss have decreased sensitivity to sound. The clarity of the sound being heard is also affected, and this happens because of the damage to the auditory nerve. Even when the sound getting to the inner ear is loud enough, the brain won't receive it.
Sensorineural hearing loss can be caused by exposure to noise, anatomical abnormalities of the cochlea, head injuries, measles, prolonged high fever, meningitis, mumps, or hereditary factors.
There is no known cure for sensorineural hearing loss yet.
2. Conductive Hearing Loss
A conductive hearing loss is a hearing loss caused by an abnormality in the outer and middle ear. The inner ear of people with conductive hearing loss functions okay, but the sound gets attenuated before it gets to the inner ear.
Conductive hearing loss can be caused by abnormal formation of the bones in the middle ear, holes in the eardrum, rupture of the eardrum, extreme wax buildup, and fluid accumulation in the middle ear, small or absent pinnas, sensitivity’s normal function.
Conductive hearing loss can be corrected with medication or surgery, depending on the cause.
3. Mixed Hearing Loss
A mixed hearing loss is a medical condition where a person suffers both sensorineural hearing loss and conductive hearing loss.
This means that damage has been done to the outer, middle, and inner ear.
The conductive hearing loss can be treated with surgery or medication, but the sensorineural hearing loss can't be corrected.
4. Unilateral Hearing Loss
Unilateral hearing loss is a condition where a person has normal hearing in one ear and suffers hearing loss in the other ear at the same time.
Unilateral hearing loss can be from birth. This is usually hard to detect because the child can respond to environmental sounds and conversations and normally communicate like people without hearing disabilities.
This makes it hard to identify the hearing loss early enough to administer the appropriate treatment where necessary.
5. Auditory Neuropathy Spectrum Disorder (ANSD)
Auditory neuropathy spectrum disorder is a different hearing issue that occurs when the hearing organ located in the ear receives sounds normally. Still, the signals being sent out of it are disorganized.
In some cases, the sound getting to the inner ear cannot be normally processed.
Although the actual causes of ANSD are not yet known, certain risk factors have been identified.
They include the following:
- Jaundice at birth
- Premature birth
- Low birth weight
- Head trauma
- Family history of ANSD.
There is no known cure for ANSD, but hearing aids can help the person process sound properly.
6. Central, Cortical or Auditory Processing Hearing Loss
This hearing loss occurs when the brain cannot interpret the sound information it receives despite the normal function of the peripheral hearing sensitivity.
Hearing Loss Causes
For the sake of this post, this section will be grouped into two; hearing loss causes in children and hearing loss causes in adults.
Hearing Loss Causes in Children
About 34 million children worldwide have disabling hearing loss. Hearing loss causes in children can be categorized under two major causes; Congenital causes and acquired causes.
Let's examine each cause.
1. Congenital Causes
Congenital hearing loss causes are factors that result in hearing loss from birth. Out of every 1000 children born in the United States, about 2 to 3 are born with hearing loss in either one or both ears.
Congenital causes can either be hereditary or non-hereditary genetic factors.
Some of the factors responsible for Congenital hearing loss are complications during pregnancy such as syphilis, and maternal rubella, birth asphyxia, low birth weight, severe jaundice, or inappropriate use of certain drugs like diuretics during pregnancy.
2. Acquired causes
Research has shown that over 90 percent of children born deaf have hearing parents.
Acquired hearing loss causes are factors that lead to hearing loss at any stage of the child's life; these causes are not genetic and have nothing to do with the child’s state at birth.
Preventable factors cause about 60 percent of childhood hearing loss.
Acquired hearing loss causes are often from exposure to certain harmful things to the child’s hearing health.
Here are some acquired causes that can lead to hearing loss;
- Otitis Media: 5 out of 6 children experience otitis media by the time they are three years old. This is the collection of fluid in the ear which occurs after the child has suffered from a viral infection such as a cold.
- Infectious Diseases: If infectious diseases are not given timely medical care, they can cause hearing loss. Infectious diseases like mumps, meningitis, and measles can degenerate to hearing loss if not properly handled.
- Certain Medications: The use of certain medicines in treating certain conditions like malaria, tuberculosis, cancers, and neonatal infections can adversely affect the child’s hearing.
- Exposure to Excessive Noise: There is a limit to how much noise the ear can handle; if a child is continuously exposed to loud noise, the hearing can get damaged.
Avoid prolonged exposure to loud recreational noise, noises from machines, explosions, bars, night clubs, and loud noise from audio devices.
- Injury to the Head or Ear: Injury to the head due to falling or massive impact from an object can tamper with the child’s hearing. Damage done to the ear from sharp objects can also affect the child's hearing.
Hearing Loss Causes in Adults
Just like in children, hearing loss can be inherited or acquired as the person gets older. In this section, we will be examining the major causes of hearing loss in adults.
Let's get started.
One of the significant causes of hearing loss in adults is noise in the workplace. People who work in places like factories where they are regularly exposed to noise from heavy machines, power tools, and equipment often suffer total or partial hearing loss.
Even though most people who work in places where noise is a regular part of the work environment often protect their ears from the noise, constant exposure to the noise, whether silenced or not, can affect the person’s hearing.
The best type of protective gear to wear is earplugs or ear protectors covering the entire ear, reducing blood the amount of noise that gets to the ear.
Recreational activities with loud noises can mess up your hearing, especially if you continuously engage in them.
While the activities may be fun, the noise associated with the activities is at dangerously high levels. Recreational activities with high noise levels include car racing, motorcycling, and snowmobiling.
Also, noises in concerts, bars, and clubs can affect hearing. Most people experience a ringing sound (tinnitus) in their ears after leaving a concert or club.
This ringing sound is caused by exposure to dangerously high levels of sound. Scientifically, any noise above 85 decibels can affect hearing, but the average decibel level of the noise at rock shows is 110. This can damage the hearing of a person in five minutes.
3. Explosive Noises
This is a significant cause of hearing loss among military personnel. Noises from explosives are so loud that they can cause sudden hearing loss, temporary or permanent.
Noise from jet engines, firearms, firecrackers, bombs, dynamites, grenades, and gunshots create powerful sound waves that can instantly damage the inner ear or rupture the eardrum.
Putting on ear protection and keeping a safe distance from the noise source are ways that you can protect your ear from getting damaged by the noise.
4. Headphones and Earbuds
Constant use of headphones and earbuds at too high volumes can cause temporary or permanent hearing loss.
The easiest way to know if the headphones’ level of sound is dangerous is to find out if other people around can hear the music you are playing through your earphones or earbuds.
The extent of the damage done to the ear is dependent on how loud the music is and how long you listen to it. Ideally, the music volume should not be more than 60 percent of the maximum volume, and earbuds and earpieces should not be used for more than one hour at a stretch.
5. Chronic Disease
Certain diseases that last long can cause hearing loss. Even though these diseases may not be directly related to the ears, some can interrupt the flow of blood to the brain or inner.
Diseases like diabetes, heart disease, autoimmune diseases, and stroke can affect a person’s hearing.
6. Meniere's Disease
This is a disease that affects the inner ear and often results in sensorineural hearing loss. People with Meniere's disease experience sensitivity to loud sounds, dizziness, and ringing in the ear.
Most hearing loss caused by Meniere disease can come and go for a while, but it can become permanent over time.
There is no known cause for Meniere disease, but it is expected between 30 and 50 years.
Otosclerosis is a health condition that occurs when there is an abnormal remodeling of the bone in the middle ear.
Bone remodeling is a normal process in every human, but when the remodeling is abnormal, sound to travel from the middle to the inner ear is disrupted.
The tiny bones in the middle ear cannot move easily, resulting in conductive hearing loss.
8. Autoimmune Inner Ear Disease
This disease is characterized by dizziness or progressive hearing loss, and it occurs when the immune cells or antibodies in the ear begin to attack the inner ear.
This disease affects the hair cells in the inner ear, responsible for both hearing and balance, so persons with this disease suffer dizziness.
If autoimmune inner ear disease is not treated fast, the damage can worsen, but the middle ear bones’ effect on hearing may be minimal if given prompt medical attention.
9. Ear Infection or Tumor
An infection in any part of the ear can lead to an infection in the hearing part of the ear, resulting in temporary or permanent hearing loss.
Also, noncancerous growths like scar tissue, cysts, and bone tumors can block the ear canal and cause hearing loss.
Removal of these growths will restore the hearing of the person. There is a rare type of tumor known as acoustic neuroma.
This tumor grows on the hearing and balance nerves in the inner ear, which results in facial numbness, loss of balance, tinnitus, feeling of fullness in the ear, and hearing loss. With the appropriate treatment, the person may be able to hear a little.
10. Ear Stroke
An ear stroke is a sudden sensorineural hearing loss which leads to a sudden loss of hearing. The hearing loss often happens in one ear and can be long term or over a few days.
There may be a root cause of the ear stroke in some cases, but there is no known cause of it in most patients.
People who experience ear stroke are advised to seek immediate medical help to avoid losing their hearing permanently.
Age is the most vital cause of hearing loss among adults aged 20-69.
Hearing loss is a common problem that most people experience when they grow older. As people get older, the hearing weakens.
This could be a cumulative effect of constant exposure to loud noise, even when the ears are protected. The sound people who suffer hearing loss at old age hear it is often unclear or muffled.
In some cases, they will only hear things said loudly, or they may always ask you to repeat what you said before they can listen.
In most cases, it may be hard for the hearing to be restored to the original state, but certain things like cochlear implants, therapy, and hearing aids can help the person hear better.
12. Pressure Changes and Injury
Serious injury to the head due to accidents or sporting activities like boxing and wrestling can damage the ear’s nerves or dislocate the bones in the middle ear, leading to permanent or temporary hearing loss.
A sudden change in pressure can damage the middle or inner ear or the eardrum, which can be experienced when scuba diving or flying.
If the inner ear is damaged, it may require surgery to avert permanent hearing loss, but if the eardrum’s damage is minimal, it will heal in a few days and restore hearing.
If the eardrum is ruptured, the hearing loss is permanent.
13. Buildup of Earwax
Earwax products in the ear canal are beneficial to the body because they protect the ear canal against bacteria and dirt.
If there is a massive buildup of earwax, the hearing of a person may be affected. When earwax buildup beyond the acceptable quantity, it can harden and block the flow of sound.
Doctors can often treat hearing loss caused by the buildup of earwax. It is not advisable to get rid of the buildup by yourself; you may also Itdamage your ear permanently.
14. Ototoxic Medications
Ototoxic drugs are drugs that can adversely affect the hearing of a person. The hearing loss caused by Ototoxic drugs is mostly temporary, but in rare cases, the loss can be permanent.
Here is a list of some of the drugs that can cause hearing loss:
- Painkillers like aspirin and ibuprofen
- Aminoglycoside antibiotics like kanamycin or streptomycin, antimalarial drugs, and chemotherapy drugs
- Diuretics like ethacrynic acid
If your doctor prescribes any of these drugs to you, he will most likely pay close attention to your hearing. If you experience any difficulty with hearing while taking any of these, don't hesitate to tell your doctor.
Rare Causes of Hearing Loss
Asides from all the common causes of hearing loss we saw above, there are rare causes of hearing loss.
Some of these health conditions are so rare that only a tiny percent of the world's population is affected by them.
Below are some of these rare conditions
This rare condition affects one in every ten thousand people, and it is caused by a non-malignant cyst-like growth in the inner ear.
There are two types of Cholesteatoma:
- Congenital Cholesteatoma
- Acquired Cholesteatoma
Congenital Cholesteatoma is present at birth and happens when skin cells grow in the wrong place, which leads to a growth behind the eardrum.
Acquired Cholesteatoma happens in adults, and chronic or recurring ear infections can cause it.
Some symptoms of Cholesteatoma are dizziness, smelly discharge from the ear, and hearing loss. If the Cholesteatoma is left untreated, the growth’s toxicity can spread to other parts of the body and cause meningitis and brain abscesses.
Also, it is left to grow; the tumor can damage the inner ear structures, which could cause balance problems and dizziness.
The growth can also interfere with facial muscles and nerves and lead to paralysis. That said, Cholesteatoma can be removed surgically.
This is a rare condition that causes the brain and ears to produce sound in disjointed ways. Some people refer to Diplacusis as double hearing because the loudness and pitch of one ear’s sound vary from the other ear’s loudness.
An echo may be heard in some cases because one ear hears the sound faster than the other.
The wearing often causes Diplacusis out of inner ear hair cells, which can be caused by constant exposure to loud noise, autoimmune disorders, head trauma, age-induced hearing loss, clogged sinuses, excessive earwax, and certain medications.
If the Diplacusis is caused by an infection or obstruction in the ear, once the block is removed or the infection is cured, the Diplacusis disappears. But if it is caused by damage to the inner ear hair cells, the damage may be permanent.
3. Superior Semicircular Canal Dehiscence Syndrome (SCDS)
This is a rare disorder that affects less than one percent of the world's population. It is caused by the presence of a tiny hole in a bone in the inner ear.
This hole causes balance disorders, vertigo, nausea, and extreme sensitivity to noise.
People with SCDS will often complain of their voice, the sound of their pulse, and even the movement of their eyeball being too loud and unbearable.
This condition can be detected with a CT scan and corrected with surgery, but certain surgical complications like nerve damage and hearing loss may occur.
4. Cogan’s Syndrome
Cogan’s syndrome is a rare autoimmune inflammatory disease that causes the ears and eyes to swell.
Although the actual cause of Cogan’s Syndrome is unknown, it is believed that it is caused by an autoimmune response that makes the body's immune system attack the tissues of the ear and eye, which results in swelling.
While some people with Cogan’s Syndrome can manage this disorder’s symptoms, others may suffer permanent visual and hearing damage.
5. Usher Syndrome
Usher Syndrome is a disorder that affects the hearing and vision of a person. It is caused by the abnormal development of hair cells in the inner ear.
People with Usher Syndrome can suffer profound hearing loss and severe balance problems. Usher Syndrome is often inherited and can be present at birth.
There is no cure for Usher Syndrome presently, but the hearing and vision problem can be managed using cochlear implants, hearing aids, and auditory training.
Hearing loss can be avoided mostly if it is noise-induced. Ensure you protect your ears from loud noise as much as possible. Limit the intensity and duration of exposure to loud noise in the workplace and at home.
Wearing earplugs and earmuffs will help protect your ear from destructive noise. Cut down on recreational activities that expose your ears to change in pressure or loud noise.
If you notice any problems with your ear, don't try to self medicate or try DIY tricks for relief; head straight to the doctor's office and get examined.
Have you suffered hearing loss as a result of any of the factors we examined in this post? Share your experience with us.