Overview
Hearing loss that occurs gradually as you age (presbycusis) is common. About one-third of people in the United States between the ages of 65 and 75 have some degree of hearing loss. For those older than 75, that number is approximately 1 in 2.
Hearing loss is defined as one of three types:
- Conductive (involves outer or middle ear)
- Sensorineural (involves inner ear)
- Mixed (combination of the two)
Symptoms
- Muffling of speech and other sounds
- Difficulty understanding words, especially against background noise or in a crowd
- Trouble hearing consonants
- Frequently asking others to speak more slowly, clearly and loudly
- Needing to turn up the volume of the television or radio
- Withdrawal from conversations
- Avoidance of some social settings
Causes
- Damage to the inner ear.
Aging and exposure to loud noise may cause wear and tear on
the hairs or nerve cells in the cochlea that send sound signals
to the brain. When these hairs or nerve cells are damaged or missing,
electrical signals aren't transmitted as efficiently, and hearing loss occurs.
Higher pitched tones may become muffled to you. It may become difficult for you to pick out words against background noise. - Gradual buildup of earwax. Earwax can block the ear canal and prevent conduction of sound waves. Earwax removal can help restore your hearing.
- Ear infection and abnormal bone growths or tumors. In the outer or middle ear, any of these can cause hearing loss.
- Ruptured eardrum (tympanic membrane perforation). Loud blasts of noise, sudden changes in pressure, poking your eardrum with an object and infection can cause your eardrum to rupture and affect your hearing.
Risk factors
- Aging Degeneration of inner ear structures occurs over time.
- Loud noise Exposure to loud sounds can damage the cells of your inner ear. Damage can occur with long-term exposure to loud noises, or from a short blast of noise, such as from a gunshot.
- Heredity Your genetic makeup may make you more susceptible to ear damage from sound or deterioration from aging.
- Occupational noises. Jobs where loud noise is a regular part of the working environment, such as farming, construction or factory work, can lead to damage inside your ear.
- Recreational noises Exposure to explosive noises, such as from firearms and jet engines, can cause immediate, permanent hearing loss. Other recreational activities with dangerously high noise levels include snowmobiling, motorcycling, carpentry or listening to loud music.
- Some medications Drugs such as the antibiotic gentamicin, sildenafil (Viagra) and certain chemotherapy drugs, can damage the inner ear. Temporary effects on your hearing — ringing in the ear (tinnitus) or hearing loss — can occur if you take very high doses of aspirin, other pain relievers, antimalarial drugs or loop diuretics.
- Some illnesses. Diseases or illnesses that result in high fever, such as meningitis, may damage the cochlea.