What You Need to Know About Hearing Loss: Causes

The audio of everyday life is important for our health. We hear our environment, have meaningful conversations and connect with our loved ones. When sounds start to fade, such as not hearing your own foot steps or turning up the volume of the TV, there is a chance you have hearing loss and hearing aids can help. The gradual onset of hearing loss can make it harder to identify. But, even in cases of mild hearing loss, hearing aids still help.

More than half of people with hearing loss are younger than 65 and genes are often the culprit. About 4 children per 1,000 children are born with partial or complete hearing loss. More than half of these cases are caused by genetic factors. If hearing loss is suspected, doctors start by looking at a person’s physical features, medical history, and family history.

Based on a doctor’s findings, hearing loss is described in many ways:

  • congenital or acquired
  • prelingual or postlingual
  • progressive or nonprogressive
  • conductive or sensorineural
  • syndromic or nonsyndromic
  • familial or sporadic.

Hearing Loss from Genes

These classifications identify certain causes. Most cases of genetic deafness (70 percent to 80 percent) are not associated with other signs and symptoms (nonsyndromic); the remaining cases are caused by specific genetic syndromes. The causes of nonsyndromic deafness are complex. Researchers have identified more than 30 genes that, when altered, are associated with nonsyndromic deafness; however, some of these genes have not been fully characterized.

Many genes related to deafness are involved in the development and function of the inner ear. Mutations in these genes contribute to hearing loss by interfering with critical steps in processing sound. Different mutations in the same gene can be associated with different types of hearing loss, and some genes are associated with both syndromic and nonsyndromic deafness.

Hearing Loss from Aging

Diabetes and vascular diseases also contribute to hearing loss which is why it’s the third most common chronic condition for geriatrics. Since our hearing is so interconnected with our health, when our health isn’t optimal, our hearing predictably degrades. The aging process also contributes to the causes of hearing loss, but the types of hearing loss are more important.

Regardless of cause, most hearing loss is classified into two categories: sensorineural or conductive. Sensorineural hearing loss is the most common form of hearing loss and it’s caused by damage to the tiny hair cells in the ear that help transmit sound to your brain. These can bend or break due to:

  • Exposure to very loud noises
  • Genetic disposition
  • Virus infections in the inner ear
  • Certain medical treatments such as chemotherapy and radiation
  • Head injury
  • Age

Conductive

Conductive hearing loss occurs when sound is not conducted efficiently through the outer ear canal to the eardrum and the tiny bones (ossicles) of the middle ear. Conductive hearing loss usually involves a reduction in sound level or the ability to hear faint sounds. This type of hearing loss can often be corrected medically or surgically.

Some possible causes of conductive hearing loss:

  • Fluid in the middle ear from colds
  • Ear infection (otitis media)
  • Allergies (serous otitis media)
  • Poor eustachian tube function
  • Perforated eardrum
  • Benign tumors
  • Impacted earwax (cerumen)
  • Infection in the ear canal (external otitis)
  • Swimmer’s Ear (otitis externa)
  • Presence of a foreign body
  • Absence or malformation of the outer ear, ear canal, or middle ear

Sensorineural

Once you experience sensorineural hearing loss, your hearing doesn’t return because the tiny hair cells within the inner ear (the cochlea) are damaged. Hearing aids are the primary treatment for sensorineural hearing loss. In some situations, such as when hearing aids have not been beneficial for particular patients with severe and profound sensorineural hearing loss, these people may benefit from cochlear implantation.

Sensorineural hearing loss can be caused by:

  • Exposure to excessive loud noise
  • Ear infections trauma or ear disease
  • Damage to the inner ear or ear drum from foreign objects
  • Illness or certain medications
  • Normal aging processes

The most important thing to know is that in most cases, you have control over one of the most common causes of hearing loss: noise. You can protect your hearing by reducing exposure to loud noises.

Noise is dangerous when:

  • You have to shout over background noise to be heard
  • ƒThe noise is painful to your ears
  • ƒThe noise makes your ears ring
  • ƒYou have decreased or “muffled” hearing for several hours after exposure

www.audiology.org_practice_resources_PublishingImages_NoiseChart85x11.pdf

Hearing Loss from Diabetes

Diabetes and hearing loss are completely separate things, right? Well, not totally. According to the American Diabetes Association:

The NIH has found that hearing loss is twice as common in people with diabetes as it is in those who don’t have the disease. Also, of the 79 million adults thought to have pre-diabetes, the rate of hearing loss is 30% higher than in those with normal blood sugar.

Hearing Loss from Disease

Hearing loss occurs naturally as we age, but it also appears to be a symptom of multiple diseases and behaviors.

About.com has a list of diseases that can cause hearing loss. Among them:

  • Adult chicken pox
  • Toxoplasmosis
  • Herpes
  • Glue Ear

About 1/3 of adults carry the toxoplasmosis parasite, but their immune system prevents it from becoming a problem. Common diseases can be triggers for hearing loss.

Hearing Loss from Behavior

Some diseases are preventable, but there is also a component of luck. Fortunately, we can control our behaviors that lead to hearing loss. According to Healthy Hearing:

Smokers are 70 percent more likely than non-smokers to suffer hearing loss, according to an article in the June 1998 Journal of the American Medical Association. The study also found that non-smokers living with a smoker were twice as likely to develop hearing loss as those who were not exposed at all.

Besides smoking, long exposures to harmful noises also causes hearing loss. Whether working at a manufacturing plant or enjoying a night out at a concert, we have the technology and ability to control what sounds are reaching our inner ear.

Hearing Loss from Obesity

We already have enough reasons to stay fit, but a major 20-year study published within the Journal of Medicine added another reason to the list when they concluded:

“Higher BMI and larger waist circumference are associated with increased risk, and higher physical activity is associated with reduced risk of hearing loss in women. These findings provide evidence that maintaining healthy weight and staying physically active, potentially modifiable lifestyle factors, may help reduce the risk of hearing loss.”

Basically, carrying extra weight puts stress on the body and the stress is associated with any number of health problems. One minor health issue can quickly cascade into more serious problems as we age. Hearing loss is mostly due to age and noise exposure, but its connected with many other factors. To further compound the problem, hearing loss can also cause more health problems such as the onset of Alzheimer’s and dementia. The key to living a healthy life is to proactively manage your health or to respond as quickly as possible when a problem arises.

Hearing Loss from Prescription Drugs

My mother had normal hearing at the age of 64. When she was diagnosed with cancer, they put her through two rounds of chemo treatment that affected her hearing. The moderate hearing loss was permanent. She received hearing aids to treat the hearing loss and it helped her make the best of the years that she had left.

Since chemo can also diminish hearing, the inability to hear can make matters worse. According to the USA Today article, Listen Up: Dementia linked to hearing loss,

“Cognitive problems developed, 30% to 40% faster when hearing declined to 25 decibels — mild hearing loss, according to the research online in the JAMA Internal Medicine. ‘That’s when you begin noticing trouble hearing and understanding in settings like a busy restaurant,’ says lead author Frank Lin.”

Chemo is toxic in more ways than one. Chemo not only kills hearing but it also kills memory, it affects cognitive function – causing dementia, also known as chemo brain:

“Research shows that some cancer drugs can cause certain kinds of changes in the brain. But it also shows that chemo and radiation aren’t the only things that can cause thinking and memory problems in people with cancer.”

Ototoxicity is often diagnosed by ruling out all other possible sources of hearing loss. It is a catch all explanation for a sudden, unexplainable hearing problem that is often medication-induced. Ototoxic drugs include:

  • Strong antibiotics such as the aminoglycoside gentamicin
  • Loop diuretics such as furosemide
  • Platinum-based chemotherapy agents such as cisplatin
  • A number of nonsteroidal anti-inflammatory drugs (NSAIDS) have also been shown to be ototoxic.

Sometimes, ototoxicity is temporary. The effects vary by each person and each medication. For those with imbalance, physical therapy helps regain walking abilities. For hearing, cochlear implants can be an option but since there is no cure, treatment is about restoring comfort and quality of life. Hearing aids help those suffering from ototoxicity maintain their social lives. Often, the hardships they are facing are difficult enough, the good news is that Vail Valley Hearing Center can help.

Hearing Loss from Heart Disease

According to a study in older adults:

The prevalence of suffering from various degrees of hearing loss is 54% greater among those who have a history of heart disease than in the general population. The study also found if individuals exercised at least once a week, they saw a 32% reduction in the risk of suffering from hearing loss, when compared to sedentary people.

Numerous studies have linked untreated hearing loss to a wide range of physical and emotional conditions, including impaired memory and ability to learn new tasks, increased risk of dementia and Alzheimer’s disease, reduced alertness, increased risk to personal safety, increased risk of falling, irritability, negativism, anger, fatigue, tension, stress, depression, decreased job earnings and diminished psychological and overall health.

Regardless of these conditions, many of us will still encounter health issues as we age. The important part is in recognizing problems before they become worse. By recognizing the problem, we can take steps to deal with it. In many health scenarios, we can either reverse the problem, slow it’s progress, or reduce the negative symptoms that result. For example, we can often prevent further hearing loss by reducing exposure to loud sounds. Then, by using a hearing aid, we can reduce potential brain atrophy.