We Do Want to Hear It!
Hearing loss is common as we age with almost 50% of people in the United States over the age of 65 having some degree of loss. The impairment can be one of three types: conductive- which involves the outer or middle ear, sensorineural- which involves the inner ear, or mixed type. The two main factors which contribute to hearing loss are aging and chronic exposure to loud noises. Most types of hearing loss are not reversible, but there are treatments.
It is helpful to understand how the ear works in order to better understand how hearing loss occurs. Sound waves pass through the outer ear and cause vibrations of the eardrum. The eardrum and three small bones in the middle ear amplify the vibrations as they travel to the inner ear. The vibrations then pass through fluid in a snail-shaped structure called the cochlea. The cochlea has nerve cells with tiny hairs which translate sound vibrations into electrical signals, which are then transmitted to the brain and translated into sound.
Issues besides age and noise exposure that contribute to conductive hearing loss include: congenital malformations, infections, trauma, abnormal growths, wax build-up and perforation of the tympanic membrane. Sensorineural loss can be due to some of the above as well as things like thyroid problems, certain medicines, Meniere disease, auto-immune disease and multiple sclerosis. Some of these things can be seen on physical exam, and others suspected with evaluating the history and timing of symptoms.
However as mentioned earlier, aging and loud noise exposure account for the majority of hearing loss in older adults. The mechanism is simply wear and tear on the hairs or nerve cells in the cochlea. Initial symptoms that might be noticed by the individual are: muffling of sounds particularly if they are soft or high-pitched, and difficulty understanding words, especially with background noise. Others might notice the person asks others to speak up, or turns the volume up on television or radio, maybe even withdraws from conversations or avoids some social settings.
Presbycusis refers specifically to age-related sensorineural hearing loss and can be associated with cognitive impairment and depression. A study from Johns Hopkins University found that mild hearing loss doubled dementia risk, moderate tripled risk and people with a severe hearing impairment were five times more likely to develop dementia. It’s not clear whether that is a direct result of the hearing loss or is related to the social isolation but it probably is both. Research suggests that treating the hearing loss can have a positive effect on cognitive performance, especially memory. I have certainly seen dramatic changes in my patients and family members when they address the hearing loss.
Measures to prevent hearing loss include protecting the ears to limit the duration and intensity of exposure to noise. This can be done with earplugs or earmuffs and is important to remember with certain jobs or recreational activities that might involve loud noises- like operating machinery, hunting, or attending concerts. It is important to have your hearing tested, which can likely be arranged by your primary physician.
The options for treatment include: hearing aids which come in a variety of styles and prices, assistive listening devices, auditory rehabilitation, and if those are not helpful, cochlear implants might be considered. Only 1 in 7 older Americans with hearing loss actually use a hearing aid and most wait 10 years before getting help. The barriers seem to be: denial about the degree of hearing impairment, not wanting to admit we are advancing in years, or the impression that hearing aids are obvious to others or difficult to use. The longer you wait, though, the more risk you are at for developing cognitive decline. So do yourself a favor- get your hearing tested and talk to someone about an option that might work for you!
For more information:
www.hearinghealthfoundation.org
Bridget M. Dewey, MD
Internal Medicine/Pediatrics
Gateway Family Health Clinic
