Presbycusis (Age-Related Hearing Loss)

What causes presbycusis?

Sound is converted to nerve signals in the cochlea, the snail-shaped inner ear, by thousands of tiny hair cells. Hair cells at the base of the cochlea, which detect high-pitched sounds, are the most exposed and the first to wear out. Unlike some animals, humans cannot regrow them.

Several age-related changes contribute:

• Loss of hair cells
• Reduced blood supply and function of the stria vascularis, which powers the cochlea
• Loss of hearing nerve fibers and connections (synapses)
• Slower processing in the brain's hearing pathways, which makes speech in noise especially difficult

Risk factors

• Lifetime noise exposure: work, music, power tools, firearms
• Genetics: age-related hearing loss runs in families
• Smoking
• Diabetes, high blood pressure and heart disease, which affect blood flow to the inner ear
• Ototoxic medicines, such as some chemotherapy drugs and aminoglycoside antibiotics
• Male sex: men tend to lose hearing earlier

Symptoms and early signs

• Speech sounds mumbled or muffled, especially women's and children's higher voices
• Mixing up words that differ by consonants ("fifty" vs "sixty")
• Hearing that people are talking but not understanding them, especially in restaurants or groups
• Asking people to repeat themselves
• Turning up the TV or radio
• Difficulty on the phone
• Not hearing the doorbell, birdsong or the microwave beep
• Ringing, buzzing or hissing in the ears (tinnitus)
• Withdrawing from social situations because conversation is tiring

Because it develops slowly, family members often notice before the person does. Many people wait years before getting help.

Presbycusis vs other causes of hearing loss in older adults

Presbycusis is a type of sensorineural hearing loss, meaning the problem is in the inner ear or nerve rather than in the ear canal or eardrum.

How it is diagnosed

1. History of noise exposure, medicines, family history and how hearing affects daily life.
2. Ear exam with an otoscope to look for wax, infection or eardrum problems.
3. Pure-tone audiogram: you press a button when you hear beeps of different pitches and volumes. Presbycusis typically shows a sloping loss, worse at high frequencies, similar in both ears.
4. Speech testing: how well you understand words, in quiet and in noise.
5. Tympanometry to check the middle ear.
6. MRI only when loss is uneven between ears or there are other neurological signs.

Hearing loss is graded as mild, moderate, severe or profound, which guides treatment.

Treatment

Hearing aids

Hearing aids are the main treatment and help most people with presbycusis. Modern aids are small, filter background noise, stream phone calls and connect to TVs.

• Over-the-counter (OTC) hearing aids: available in the US since 2022 without a prescription or exam for adults 18 and older with perceived mild to moderate hearing loss. They cost less but you fit them yourself.
• Prescription hearing aids: fitted and programmed by an audiologist or hearing aid specialist; better for moderate to severe loss, complex needs or those who want professional adjustment.

Wearing them consistently, most of the day, gives the best results. The brain needs a few weeks to adapt.

Other options

• Assistive listening devices: TV streamers, amplified phones, captioned phones, hearing loops in theaters and churches
• Captioning on TVs, video calls and phones
• Cochlear implants for severe to profound loss when hearing aids no longer help with understanding speech. Many older adults benefit greatly
• Auditory training and lip-reading classes

Communication tips for families

• Face the person, in good light, and get their attention first
• Speak clearly at a normal pace; do not shout
• Reduce background noise, such as turning off the TV
• Rephrase rather than repeat the same words

Why treating hearing loss matters

Untreated hearing loss is linked to social isolation, depression, falls and faster cognitive decline. The Lancet Commission on dementia identified midlife hearing loss as one of the largest modifiable risk factors for dementia. Research suggests that hearing aids may slow cognitive decline, especially in people at higher risk.

Prevention

Age-related changes cannot be stopped, but you can protect the hearing you have:

• Use earplugs or earmuffs around loud noise, such as mowers, concerts and power tools
• Keep personal music at no more than about 60% volume for limited periods
• Do not smoke
• Control blood pressure and diabetes
• Have your hearing checked regularly after age 50, or sooner if you notice changes

Frequently asked questions

What is presbycusis?

Presbycusis is age-related hearing loss: a gradual decline in hearing in both ears caused by aging of the inner ear and hearing nerve. High-pitched sounds are affected first, so speech becomes muffled and hard to follow in noise. It is the most common cause of hearing loss in older adults.

At what age does presbycusis start?

Changes often begin in the 40s or 50s, but most people do not notice until their 60s or later. About a third of adults aged 65 to 74 and around half of those over 75 have hearing loss. Noise exposure, genetics and health conditions affect how early it starts.

Can presbycusis be reversed?

No. The hair cells and nerve fibers lost with age do not regrow, so presbycusis is permanent and usually progresses slowly. Hearing aids, cochlear implants and assistive devices can restore much of the ability to communicate, and research on regenerating hair cells is ongoing.

Are over-the-counter hearing aids good for age-related hearing loss?

They can be a good option for adults with mild to moderate presbycusis, offering lower cost and easy access. People with more severe loss, hearing loss in one ear only, ear pain, discharge or sudden changes should see a doctor or audiologist first.

Does hearing loss increase the risk of dementia?

Studies consistently link untreated hearing loss with faster cognitive decline and a higher risk of dementia. It is considered one of the largest modifiable risk factors. Treating hearing loss with hearing aids may help protect thinking skills, as well as improving social life and mood.