Gradual loss of hearing that develops as a natural part of aging
Many people over the age of 50 notice that they find it hard to hear quiet or high-pitched sounds and conversation is sometimes difficult to understand, particularly when there is background noise, such as music. Over a period of years, sounds of all pitches may become increasingly difficult to hear. This progressive decline in hearing is known as presbyacusis and is a common feature of the normal process of aging.
Presbyacusis occurs in about 1 in 5 people aged 50–60, 1 in 3 people aged 60–70, and half of all people over 70. The condition is more common and severe in men and may run in families.
The body’s sensory receptor for hearing, located in the cochlea in the inner ear, is lined with sensory hair cells. Presbyacusis occurs when these sensory hair cells degenerate and die with age. The condition is occasionally more severe in people whose hearing has already been damaged by exposure to excessive levels of noise (see Noise-induced hearing loss) or by previous middle- or inner-ear problems, such as a perforated eardrum.
The symptoms of presbyacusis develop gradually and may include:
Loss of hearing, initially of high-pitched sounds and gradually of lower pitches.
Difficulty in hearing speech, especially with noise in the background.
Loss of sound clarity, so that even loud speech is difficult to understand.
Both ears are usually affected, although not always equally. The severity and progression of hearing loss vary from person to person. Severe hearing loss sometimes leads to feelings of isolation, loneliness, and depression.
Your doctor will examine your ears with a viewing instrument called an otoscope (see Otoscopy). He or she may also arrange for various hearing tests to determine the type and degree of hearing loss (see Hearing tests). There is no cure for presbyacusis. However, a hearing aid may improve your ability to hear and communicate.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.