Study: Adults with Hearing Loss More Susceptible to Cognitive Impairment

Hearing loss is prevalent in almost two-thirds of adults over the age of 70, and it remains undertreated. Over the past several years, medical researchers have begun to piece together the links between hearing loss and cognitive decline that may ultimately lead to dementia. Though there are a number of possible causes of dementia in the elderly, preventive hearing care measures and more aggressive treatment of hearing impairment can help keep the brain healthy and active.

A 2012 study headed by Johns Hopkins Center on Aging and Health researcher and medical doctor Frank Lin demonstrated this link a little more clearly. In the peer- reviewed paper “Hearing Loss and Cognitive Decline in Older Adults,” (published in the Journal of the American Medical Association), Lin et al. discovered through baseline cognitive testing that those with at least a mild hearing loss (a 25-dB loss) showed a cognitive impairment 24 percent more often than those with healthy hearing.

Because the prevalence of dementia is projected to double every 20 years, it’s important to look at possible factors and preventive measures for cognitive decline. The results of this study indicate that hearing loss is independently associated with decreased cognitive functioning and incident dementia, that is, new cases that develop over the course of the study. This 6-year study is an important step toward understanding how hearing rehabilitation might help curb or delay developing cases of dementia.

In a later analysis of individuals who remained dementia- free, accelerated rates of cognitive decline were still observed in those with hearing loss. Based on the testing methods used in this study, individuals with hearing loss would require 7.7 years to experience a decline, whereas individuals with normal hearing would require 10.9 years. In other words, those with hearing loss demonstrated a 30 to 40 percent more accelerated rate of cognitive decline. These results are consistent with prior research that demonstrated significant associations between hearing loss and poor cognitive function.

Those with hearing difficulties can see improvements in their cognitive load through aural rehabilitation methods and hearing loss treatments, like hearing aids. Better hearing health means a higher quality of life for patients, their families, and their friends — and that means good things for our entire local community.

Lin FR, et al. Hearing Loss and Cognitive Decline in Older Adults. Journal of the American Medical Association. 2013;173(4):293–299.