When Johns Hopkins researchers demonstrated a strong correlation between hearing loss and dementia, they confirmed previous research on the same subject but failed to answer what the study’s author termed “the 50-billion-dollar question”—whether hearing aids or cochlear implants correcting hearing loss could serve to prevent the onset of dementia.
The new study, published in the Archives of Neurology, used data collected by the Baltimore Longitudinal Study on Aging to follow more than 600 dementia-free adults between the ages of 36 and 90 for an average of 12 years. Those who had hearing loss at the start of the study were significantly more likely to develop dementia: those with mild, moderate, and severe hearing loss had twofold, threefold, and fivefold, respectively, the risk of developing dementia over time.
But according to the principal author of the study, ear surgeon Frank Lin, M.D., Ph.D., the results do nothing to answer the most obvious questions it raises: Might hearing loss be a cause of dementia? Or does hearing loss simply accompany dementia, without any cause or effect? Can diagnosed hearing loss can be used to predict onset of dementia? And that 50-billion-dollar question: can hearing correction enabling seniors to communicate better actually fend off onset of dementia? Additional research will be required to answer any of these questions, let alone understand why there is a connection at all. Two earlier studies, one in 1989 and another in 2008, came to a similar conclusion but left open the same questions.
“We really need to begin studying what the exact mechanism is,” Lin told Fox News. “And we need to begin studying whether hearing aids could have an effect on the onset of dementia.”
audiologists says
This extra effort in the initial stages of speech perception uses processing resources that would otherwise be available for downstream operations, such as encoding the material in memory or performing higher-level comprehension operations.
audiologists
nancy peterson says
My mother had a cochlear implant at age 79 and has done remarkably well. She is now 84 and is having some memory loss. At times it seems she isn’t hearing as well or just does not understand what we are saying. Does the memory loss affect her ability to hear with the implant?
Dianrez says
Worthwhile questions. However, in another study it was found that people who had active social interactions in their lives were less prone to dementia than those who were isolated. Also, people who had high verbal ability as shown by extensive diary writing were more resistant to dementia than those with less verbal expression.
It may not be that hearing is the main factor associated with, or predictive of dementia. It may be the RESULTS of hearing, i.e. social interaction.
Studying people who have been deaf all their lives and who use visual communication should make this clearer. Also, study of deaf people who have excellent written English. While they also are not immune from dementia, it could spotlight directions for further research.