What Causes Hearing Loss?
Hearing loss, which happens when sound signals don’t reach the brain, can result from several causes, which fall into two primary categories, according to the National Health Service:
Sensorineural Hearing Loss: This type of hearing loss results from damage to the hair cells in the inner ear or damage to the auditory nerve, which can occur naturally as a result of aging or as the result of an injury. Also called nerve-related hearing loss, sensorineural hearing loss is permanent and often will require a hearing aid to correct.
Conductive Hearing Loss: This type of hearing loss typically is caused by a problem with the ear canal, eardrum or the bones in the middle ear, according to the HLAA. It is the result of sounds being unable to travel from the outer ear to the inner ear, resulting from blockages or conditions such as glue ear, in which the middle ear fills with glue-like fluid, dulling hearing. Most forms of conductive hearing loss are temporary and can be treated effectively with medications or minor surgical procedures.
What Are Common Causes of Sensorineural Hearing Loss?
While only your doctor can make an accurate diagnosis of the cause of your form of hearing loss, these are some common causes of sensorineural hearing loss. If you have one or more of the following risk factors, you should share this information with your doctor to help in making a proper diagnosis.
Age
The most common cause of hearing loss, by far, is age – called age-related hearing loss or presbycusis. Most people will suffer some degree of age-related hearing loss, beginning around the age of 40, with the degree of hearing loss worsening as we age. According to NHS, most people have developed significant hearing loss by the age of 80.
With age-related hearing loss, high-frequency sounds become difficult to hear or discern, and certain consonants, such as “s,” “f” and “th,” become difficult to hear, which can make understanding conversations with background noise quite difficult.
Noise
Chronic exposure to loud noises is another common cause of hearing loss. This type of hearing loss, known as noise-induced hearing loss, is caused by the hair cells in the inner ear becoming damaged. This type of hearing loss often affects people who work in noisy environments, such as factories or construction, or in concert venues or nightclubs. It’s also a common result of listening to high-volume music through headphones.
While this form of hearing loss is commonly the result of people who are exposed to loud noises over a long period of time, it also can happen suddenly as a result of being exposed to an exceptionally loud noise, such as an explosion. This sudden hearing loss is called acoustic trauma. Other traumas, such as head injuries, can result in hearing loss.
Genetics
Sensorineural hearing loss can be the result of genetic abnormalities, in which people are born deaf or become deaf as a result of genetics.
Viral Infections
Viral infections of the inner ear or auditory nerve, which can include mumps, measles or rubella, also can cause damage to the hair cells in the inner ear or the auditory nerve. It also can result from a meningitis infection or from encephalitis, which is an inflammation of the brain.
Ménière's disease
Ménière's disease is a condition that causes periods of hearing loss, which are often accompanied by vertigo spells, tinnitus and feeling like there is a blockage in the ear.
Acoustic Neuroma
An acoustic neuroma is a benign (non-cancerous) growth that occurs on or near the auditory nerve, resulting in hearing loss.
Multiple Sclerosis
Hearing loss is a common symptom associated with the onset of multiple sclerosis (MS), an autoimmune condition that causes the body to attack the central nervous system.
Stroke
When the blood supply to the brain is cut off, as in the case of a stroke, hearing loss can result.
Medications and Medical Treatments
Along with chronic health conditions, certain treatments such as chemotherapy or radiation therapy for nasal or sinus cancer, according to NHS, can result in hearing loss, as well as certain medications and antibiotics, which potentially can cause damage to the cochlea in the ear or the auditory nerve.
Chronic Medical Conditions
In some cases, chronic health conditions, which include diabetes, kidney and cardiovascular disease, can put a patient at an increased risk of hearing loss.
What Are Common Causes of Conductive Hearing Loss?
Unlike sensorineural hearing loss, conductive hearing loss often comes on more suddenly, the result of an injury, trauma or blockage, and the hearing loss is usually temporary. If you’ve injured yourself cleaning out your ears, for example, and experienced hearing loss, you most likely suffer from temporary, or conductive, hearing loss. Here are some common causes.
Perforated Eardrums
A perforated eardrum – or condition in which the eardrum has a hole in it or has been torn -- can cause conductive hearing loss. This is a common cause of hearing loss in toddlers or young children whose parents use cotton swabs to clean out ear canals and push them too far inside.
Trauma of Blockage
An injury to the hearing bones, collapsed ear drum or other trauma to the ear can lead to conductive hearing loss, as well as swelling that forms around the Eustachian tube, which can be caused by surgery or radiotherapy for certain kinds of cancer.
The presence of a foreign object that physically blocks the ear canal, or a buildup of earwax called impacted earwax, can lead to conductive hearing loss.
Ear Glue
Ear glue, or a buildup of fluid in the ear, can cause conductive hearing loss. This can be the result of a cold or flu virus, an ear infection or allergies.
What Are My Treatment Options?
Depending on the type of hearing loss you’ve suffered, your doctor may be able to perform minor surgery or medical procedures to correct the damage, such as in the case of impacted earwax or a malformation in the middle ear structures. However, if you are diagnosed with a form of sensorineural hearing loss, your hearing loss is likely permanent, and your doctor can work with you to find a discreet hearing aid that will restore some hearing function.