Awareness about hearing health and recognition of early hearing loss symptoms remain some of the lesser addressed medical problems across the world. Compounding the difficulty is the scarcity of qualified hearing health services and an inability of a large slice of the populace to access such services regularly.
For example, India, with a population of 1.2 billion, has only about 2000 audiologists who are qualified to diagnose hearing loss correctly and recommend a hearing management and treatment regimen.
What is hearing loss?
You hear when the hair cells within your inner ear respond to auditory stimuli and transmit the sound as an electrical signal to the brain for processing.
Hair cells are of two types: auditory and vestibular. These hair cells are of paramount importance for hearing (auditory) as well as maintenance of inner ear balance (vestibular). Hair cells, once damaged, cannot be regenerated, leading to permanent hearing loss (sensorineural hearing loss) and problems with balance, such as, dizziness and disorientation if they are not cared for properly.
While hearing aids can provide a hearing mechanism to compensate for damage to auditory hair cells, there is no such mechanism for vestibular hair cell damage.
Sensorineural loss is the most common type of hearing loss. Hearing loss can also be conductive (problems with outer or middle ear), mixed (mix of conductive and sensorineural) and be caused by damage to the auditory nerve in the brain (central deafness). Conductive hearing loss is temporary in some cases and can sometimes be corrected by medication or by surgery.
What causes hearing loss?
Aging, heredity, head trauma, exposure to noise, certain medications, illness, congenital defects in the ear are all some causes of hearing loss. Sometimes you can experience hearing loss due to buildup of earwax in your ear or because of an ear infection. These are curable medical issues and can be managed with proper medical treatment.
Human hearing range typically falls between 20Hz to 20000Hz. Hearing range varies by individual and it deteriorates as you age. Loss of hearing ability as you grow older is normal and gradual. Young people can hear frequencies that cannot be discerned by older people.
In a study by Annie N. Simpson and colleagues and JAMA Otolaryngology-Head & Neck Surgery, it is mentioned that:
Age-related hearing loss affects more than 60 percent of U.S. adults older than 70 years; the onset is gradual, with prevalence tripling from the age of 50 years to 60 years. However, the association between hearing loss in older middle-aged adults (age 55-64 years).
Source: Middle-aged adults with hearing loss have substantially higher health care costs (http://www.eurekalert.org/pub_releases/2016-04/tjnj-maw040616.php)
Try this simple test to check how old your ears are and if you are hearing correctly for your age group. The test displays the typical frequencies heard by people in various age groups:
- 8000 Hz - Everyone
- 12000 Hz - Under 50
- 15000 Hz - Under 40
- 16000 Hz - Under 30
- 17000 Hz - Under 24
- 19000 Hz - Under 20
Source: AsapSCIENCE - How old are your ears? (https://www.youtube.com/watch?v=VxcbppCX6Rk)
Your environment and hearing loss
The environment around us is riddled with noise. Noise at a busy traffic signal, the continuous sound of a car driving at high-speed on a highway, building or road construction noise and loud volume in headphones are some of the everyday sounds we deal with that can damage hearing if ears are exposed to them continuously. For example, continuous exposure to loud city traffic for more than four hours can lead to permanent hearing damage. Some noises are more dangerous: listening to music at extremely high volume can damage your hearing within minutes.
What are the degrees of hearing loss?
Hearing loss is tested for frequencies ranging from 250 to 8000 Hertz (Hz). Using audiometry, sounds at different pitches and loudness levels are played and the ability of a person to hear the sounds are plotted on a graph. These frequencies are used because most sounds of speech lie in the frequency range of 300-5000 Hz; the audiometry frequencies of 250 to 8000 Hz are chosen because most of the auditory information needed for a satisfying hearing experience lie in this range. This helps the audiologist know if hearing loss is present at those frequencies, which speech sounds are not heard and thus fine tune the hearing aid accordingly.
The following audiogram shows position of speech sounds and some other environmental sounds, for example, bird chirping is a sound with high frequency at 4000 Hz and has an intensity of 0-5 decibels (dB).
The table below presents a classification of the degrees of hearing loss:
| Degree of Hearing Loss | Hearing Loss Range (dB HL) |
|---|---|
| Normal | –10 to 15 |
| Slight | 16 to 25 |
| Mild | 26 to 40 |
| Moderate | 41 to 55 |
| Moderately severe | 56 to 70 |
| Severe | 71 to 90 |
| Profound | 91+ |
Source: Degree of Hearing Loss (http://www.asha.org/public/hearing/Degree-of-Hearing-Loss/)
How loud is too loud?
The Centers for Diseases Control and Prevention (CDC), USA points out information that exposure to every 3 dB of noise above 85 dB decreases by half the amount of noise exposure time to cause permanent hearing loss. The pictorial below by Dangerous Decibels sums up the exposure time to noise before potential damage to hearing occurs:
Source: Decibel Exposure Time Guidelines (http://dangerousdecibels.org/education/information-center/decibel-exposure-time-guidelines/)
As an example, traffic noise at a busy signal can go up 85 dB. A study by Awaaz Foundation, Mumbai cited in the Hindustan Times pointed out:
A detailed study carried out by NGO Awaaz Foundation in 2015 for noise generated from different vehicles in the city, two-wheelers showed average noise levels up to 90dB, while the maximum permissible level is 75dB. Three-wheelers such as autorickshaws showed consistent noise levels between 77 dB and 85 dB as against 77dB, passenger cars, including taxis up to 80-82 dB with permissible levels of 75dB, and trucks between 80–95dB as against 82dB.
Source: Mumbai: Maximum city, maximum noise (http://www.hindustantimes.com/mumbai/mumbai-maximum-city-maximum-noise/story-SJuTXHLtJorwatsaUJoCDN.html)
Hearing loss awareness
Loss of hearing can be isolating and cut a person off from other people and activities. Awareness about hearing loss helps you remain cognizant about your hearing health and assess quickly any early signs of hearing loss. With this knowledge, you can not only take corrective action as soon as you discern a problem but also educate others about hearing health management.
As sensorineural hearing loss is not reversible, early preventive and corrective actions, such as wearing hearing aids on the advice on qualified medical professionals, can reduce the escalation of hearing loss, ascertaining a better quality of life.
For children, especially, early detection of hearing loss and establishment of a hearing rehabilitation program can help immensely to ensure their language and social development skills.
Benefits of hearing aids
Hearing aids compensate for hearing loss and provide a variety of benefits. Though hearing aids cannot restore hearing, they make your life comfortable by helping you to:
- communicate better
- listen in noisy environments
- delight in activities such as conversations, listening to music, watching TV
Quadio is committed to creating hearing awareness through campaigns, mobile clinics and hearing checkup camps all across India.
Quadio also designs inclusive forward-thinking hearing solutions, created to suit your requirements, enabling you to hear what you want, when you want, how you want and just the way you want.
The highly-qualified team at Quadio is trained to help you understand your hearing loss and find effective solutions allowing you to enjoy all your favourite activities without any encumbrances.
Quadio's hearing aids come with a variety of features, such as long-lasting rechargeable batteries, bluetooth compatibility, app-based customizations and with full binaural support at an affordable price, all designed to provide you the maximum benefit from your listening experience.