Presbycusis Explained: What Are the Symptoms & Treatments?

It’s common knowledge that we gradually lose our hearing ability as we grow older. The medical term for age-related hearing loss is presbycusis. 

Whether you are an older Australian worried about the onset of hearing loss or a family member looking into hearing loss treatments for your loved one, this guide will help you understand the symptoms of presbycusis and the steps you can take when experiencing age-related hearing loss.

What Causes Presbycusis?

As our bodies age, the parts of our ear and brain responsible for hearing function less effectively, resulting in Presbycusis.

The ear’s ability to hear sounds is dependent on a complex system of hair cells in the cochlea, the ear drum, the inner ear, nerve fibres, and the area of the brain that processes audio signals. Just like how bones and muscles deteriorate as we age, these parts of the hearing system also wear down – which ultimately affects how well we can hear. 

Research has shown that existing or past damage to hearing can accelerate the development of presbycusis. A 2015 paper in the Journal of Neuroscience found that continued exposure to loud noises above 85 dB (like construction noise, or listening to music at a high volume) can cause damage to the sensory hair cells in the cochlea that also have a compounding effect on age-related hearing loss. 

Types of Presbycusis

The symptoms of age-related hearing loss will depend on which parts of the hearing system are affected. The main types of presbycusis are:

Sensory Presbycusis

Sensory presbycusis is caused by a loss of inner hair cells in the basal region of the cochlea. This is the most common type of age-related hearing loss and affects a person’s ability to hear higher frequency sounds. 

Neural Presbycusis

Neural presbycusis is caused by a loss of nerve fibres that carry auditory signals from the inner ear to the brain. While the ‘listening’ parts of the ear may still be functioning well, the reduced number of nerve fibres cannot fully transmit all the signals – leading to some loss in hearing ability, especially in the area of speech perception.

Metabolic or Stria Presbycusis

Metabolic presbycusis is caused by a degeneration of the stria vascularis, the structure responsible for maintaining the chemical/electrical environment needed for hearing signal transmission. This type of age-related hearing loss affects all frequencies evenly and tends to affect listening clarity the most. 

Mechanical or Cochlear Conductive Presbycusis

Caused by a stiffening or thickening of the basilar membrane that impairs how sound waves are received, cochlear conductive presbycusis results in progressive hearing loss starting from higher-frequency sounds. 

These types of presbycusis are not mutually exclusive; some people have a combination of one or more types of age-related hearing loss. It will be difficult to know what type of presbycusis you have without undergoing a diagnostic hearing test conducted by an audiologist.

What Are the Early Signs of Presbycusis?

Presbycusis typically starts developing from the age of 70, but there are also cases of people 60 year olds experiencing age-related hearing loss due to prior hearing damage. 

Presbycusis also results in bilateral hearing loss, meaning it affects both ears rather than only one side. 

If you or your loved one is aged 60 and above and has experienced the following symptoms, they may have presbycusis. 

• Inability to hear higher-frequency sounds 

• Frequently asking others to repeat themselves or hearing muffled speech from others 

• Difficulty distinguishing similar-sounding words (like chair vs share,  save vs shave)

• Struggling to make out speech in group conversations or noisy environments like a restaurant

• Having to turn up the volume on the TV or on headphones much higher than usual

• Hearing a constant hissing, ringing, or buzzing sound (tinnitus – this is a commonly paired condition of age-related hearing loss)

What Are the Treatment Options for Presbycusis?

Presbycusis is a degenerative condition – lost hair cells and damaged nerve fibres cannot be regenerated or repaired. While there is no way to reverse hearing loss, there are treatments to help restore functional hearing and provide older individuals with a better quality of life. 

Hearing aids

Hearing aids are designed to amplify sound in a way that compensates for the type of age-related hearing loss experienced. Advanced models of hearing aids from the Oticon range now come with AI sound processing chips that further refine speech clarity in noisy environments. 

Before getting a hearing aid, individuals must undergo a hearing test with an audiologist. The results of the test will be displayed on an audiogram, which the audiologist will rely on to recommend the right hearing aid model and configure it specifically to an individual’s hearing needs.

Cochlear implants

Cochlear implants are effective for addressing those with severe-to-profound hearing loss. A cochlear implant completely bypasses the hair cells to transmit auditory signals directly through the nerve fibres. 

Cochlear implants are only recommended when hearing aids are ineffective or unsuitable for the type and severity of presbycusis. Hearing aid devices are the default treatment option for most cases of age-related hearing loss.