The most common type of hearing loss is presbycusis, or age-related hearing loss. Diminished hearing is a common side effect of aging, usually coming on gradually and affecting high-pitched sounds most frequently.
It occurs as a result of natural changes in the inner ear of an individual over time due to a variety of reasons including constant, cumulative daily noise exposure; hereditary factors; changes in the blood supply to the ear thanks to heart disease, high blood pressure, vascular conditions and circulatory problems; and side effects of some medications.
An estimated one-third of adults aged 65 or older experience age-related hearing loss; that number jumps to nearly 50 percent by the age of 75. Presbycusis usually affects both ears equally. It may be mild, moderate or severe.