Hearing Loss

Causes

Hearing loss can be caused by physical changes in the ear, the auditory nerve, or the ability of your brain to process sound. Sometimes, all three might be involved.  

Age-Related Changes in the Ear

When you age, the outer part of the ear canal thins and earwax gets drier and stickier. This increases the risk of impacted wax. Most significant changes take place in the cochlea. These changes can include the loss of sensory cells and degenerative changes in the nerve fibers that carry information from the sensory cells to the brain.

Main Types of Hearing Loss

Conductive Hearing Loss

With this type of hearing loss, your hearing is muffled. It is typically caused by a build-up of ear wax. It is normal for all ears to have some wax since it helps to protect the outer ear canal. However, excessive earwax can block the ear canal and prevent sound from entering. Your primary healthcare provider can diagnose and remove the wax if there is an excessive build-up.  

Other causes of conductive hearing loss include infections in the skin lining the ear canal, fluid in the middle ear, arthritis that affects the bones of the ear, or a hole in the eardrum. None of these causes are very common in older people. One condition that affects older individuals and causes conductive hearing loss is Paget’s disease of bone.

Sensorineural Hearing Loss 

This is the most common type of hearing loss in older adults. It is typically caused by changes or damage to the hair cells and/or nerves in the cochlea. The main cause is age but excessive noise exposure and ototoxicity (damage to the inner ear caused by drugs or chemicals) can contribute as well.

Other causes of sensorineural hearing loss include genetics or blood vessel problems (including those related to diabetes).

More rarely, sensorineural hearing loss may be related to:

  • Occupational and environmental factors such as chemical exposures
  • Certain autoimmune diseases
  • Nerve tumors
  • Infections such as herpes and influenza
  • Cigarette smoking

Older adults with the following conditions are more likely to experience hearing loss:

  • Dementia
  • Diabetes
  • Cerebrovascular disease (conditions that affect blood flow to the brain)

Dual sensory impairment (for example, vision and hearing loss at the same time) is a significant problem for at least 30% of older adults.

One type of sensorineural hearing loss is called “central hearing loss.” This occurs when you lose the ability to understand speech in situations like the presence of competing noise, competing conversation, or in environments where sound can echo. Sudden sensorineural hearing loss (loss that occurs over 72 hours) often has no identifiable cause. The primary symptom is the sensation of a full or blocked ear. If you have sudden ear blockage or fullness, contact your healthcare provider promptly to avoid any treatment delay. Treatment may include corticosteroids taken by mouth or by ear drops.

Mixed Hearing Loss

A third type, mixed hearing loss, is a combination of conductive and sensorineural hearing loss.

 

Last Updated June 2020