According to the National Institute on Deafness and other Communication disorders, “Nearly 25 percent of those aged 65 to 74 and 50 percent of those who are 75 and older have disabling hearing loss.” The proportion of adults age 70 years and older with hearing loss who have ever used hearing aids is increasing.

Information about age-related hearing loss from:

Hearing loss can be misdiagnosed as dementia and hearing loss can cause the degree of dementia to be over-estimated.  Either can happen due to use of cognitive tests that depend on being able to hear and understand spoken language and/or because of some similarities between the characteristics of hearing loss and dementia.   (e.g. Lack of understanding, social isolation, depression).  See:

Untreated hearing loss can affect the ability to communicate with family, friends and others, engage in social or group activities, live independently, feel self-confident, hear the doorbell or phone ring, play card/board games, and/or play sports. Thus, multiple articles and studies emphasize that hearing loss can cuase or contribute to social isolation and/or loneliness.