Hearing loss, deafness, hard of hearing, anacusis, or hearing impairment (a term considered derogatory by many in the deaf community), is a partial or total inability to hear. In children it may affect the development of language and can cause work related difficulties for adults.
It is caused by many factors, including: genetics, age, exposure to noise, illness, chemicals and physical trauma. Hearing testing may be used to determine the severity of the hearing loss. While the results are expressed in decibels, hearing loss is usually described as mild, mild-moderate, moderate, moderately severe, severe, or profound. Hearing loss is usually acquired by a person who at some point in life had no hearing impairment.
There are a number of measures that can prevent hearing loss and include avoidance of loud noise, chemical agents, and physical trauma. Testing for poor hearing is recommended for all newborns. But, in some cases such as due to disease, illness, or genetics, it is impossible to reverse or prevent. Hearing aids are partially effective for many. Depending on the kind of hearing loss, hearing implants can be effective.
Globally hearing loss affects about 10% of the population to some degree. It caused moderate to severe disability in 124 million people as of 2004 (108 million of whom are in low and middle income countries). Of these 65 million developed the condition during childhood. It is one of the most common medical conditions presenting to physicians. It is viewed by some in the deaf community as a condition, not an illness. Treatments such as cochlear implants have caused controversy in the deaf community.
What is Hearing Loss?
Hearing loss is a common problem caused by noise, aging, disease, and heredity. Hearing is a complex sense involving both the ear's ability to detect sounds and the brain's ability to interpret those sounds, including the sounds of speech. Factors that determine how much hearing loss will negatively affect a person’s quality of life include
- the degree of the hearing loss
- the pattern of hearing loss across different frequencies (pitches)
- whether one or both ears is affected
- the areas of the auditory system that are not working normally—such as the middle ear, inner ear, neural pathways, or brain
- the ability to recognize speech sounds
- the history of exposures to loud noise and environmental or drug-related toxins that are harmful to hearing
A Common Problem in Older Adults
Hearing loss is one of the most common conditions affecting older adults. Approximately 17 percent, or 36 million, of American adults report some degree of hearing loss.
There is a strong relationship between age and reported hearing loss: 18 percent of American adults 45-64 years old, 30 percent of adults 65-74 years old, and 47 percent of adults 75 years old, or older, have a hearing impairment.
Men are more likely to experience hearing loss than women.
People with hearing loss may find it hard to have a conversation with friends and family. They may also have trouble understanding a doctor's advice, responding to warnings, and hearing doorbells and alarms.
Types of Hearing Loss
Hearing loss comes in many forms. It can range from a mild loss in which a person misses certain high-pitched sounds, such as the voices of women and children, to a total loss of hearing. It can be hereditary or it can result from disease, trauma, certain medications, or long-term exposure to loud noises.
There are two general categories of hearing loss.
- Sensorineural hearing loss occurs when there is damage to the inner ear or the auditory nerve. This type of hearing loss is usually permanent.
- Conductive hearing loss occurs when sound waves cannot reach the inner ear. The cause may be earwax build-up, fluid, or a punctured eardrum. Medical treatment or surgery can usually restore conductive hearing loss.
What is Presbycusis?
One form of hearing loss, presbycusis, comes on gradually as a person ages. Presbycusis can occur because of changes in the inner ear, auditory nerve, middle ear, or outer ear. Some of its causes are aging, loud noise, heredity, head injury, infection, illness, certain prescription drugs, and circulation problems such as high blood pressure.
Presbycusis commonly affects people over 50, many of whom are likely to lose some hearing each year. Having presbycusis may make it hard for a person to tolerate loud sounds or to hear what others are saying.
Tinnitus: A Common Symptom
Tinnitus, also common in older people, is a ringing, roaring, clicking, hissing, or buzzing sound. It can come and go. It might be heard in one or both ears and be loud or soft.
Tinnitus is a symptom, not a disease. It can accompany any type of hearing loss. It can be a side effect of medications. Something as simple as a piece of earwax blocking the ear canal can cause tinnitus, but it can also be the result of a number of health conditions.
If you think you have tinnitus, see your primary care doctor. You may be referred to an otolaryngologist -- a surgeon who specializes in ear, nose, and throat diseases -- (commonly called an ear, nose, and throat doctor, or an ENT). The ENT will physically examine your head, neck, and ears and test your hearing to determine the appropriate treatment.
Hearing Loss Can Lead to Other Problems
Some people may not want to admit they have trouble hearing. Older people who can't hear well may become depressed or may withdraw from others to avoid feeling frustrated or embarrassed about not understanding what is being said. Sometimes older people are mistakenly thought to be confused, unresponsive, or uncooperative just because they don't hear well.
Hearing problems that are ignored or untreated can get worse. If you have a hearing problem, you can get help. See your doctor. Hearing aids, special training, certain medicines, and surgery are some of the choices that can help people with hearing problems.