New Research Shows Hearing Aids Can Help Protect Against Dementia in Older Adults
According to a new study published in The Lancet, older adults who are at a higher risk for dementia may be able to protect themselves against cognitive decline by using hearing aids. The study found that the use of hearing aids can reduce the risk of cognitive decline by about half for adults with more risk factors for dementia. These risk factors include elevated blood pressure, higher rates of diabetes, lower education and income, and living alone.
The study, which was presented at the Alzheimer’s Association International Conference in Amsterdam, came as a pleasant surprise to researchers. “It came as a surprise in a good way, seeing that hearing intervention had such a large effect on reducing cognitive decline,” said Frank Lin, lead author of the study and professor at Johns Hopkins University School of Medicine. Lin emphasized the importance of hearing health and the need for people to get their hearing checked, especially if they are unaware of any hearing loss.
Hearing loss is a common issue worldwide, but it is often untreated, particularly in lower- and middle-income countries. The World Health Organization predicts that nearly 2.5 billion people will have some form of hearing loss by 2050, and at least 700 million people will require assistance with their hearing. Age-related hearing loss has been linked to a higher risk for dementia, accounting for over 8 percent of all dementia cases.
The three-year randomized controlled trial studied nearly 1,000 older adults between the ages of 70 and 84. The participants were divided into two groups: older adults in an ongoing study of cardiovascular health and a healthier group than the former. When the two groups were combined, hearing aids did not show a significant effect on slowing cognitive changes. However, when the higher-risk group was analyzed separately, hearing intervention had a significant impact on reducing cognitive decline.
While the study highlights the positive effects of hearing aids on cognitive decline, it is still unknown whether hearing treatment can reduce the long-term risk of developing dementia. Lin and his colleagues are planning a long-term follow-up study to investigate this question further.
Previous studies have attempted to understand why individuals with hearing loss tend to have worse cognition. One theory suggests that the brain expends a lot of effort to understand speech, leaving fewer cognitive resources to process the meaning of what is heard. Another theory relates to the shrinking of the temporal lobe in individuals with hearing loss, which could have cascading effects on brain structure and function. Lastly, people with hearing loss tend to be less social, resulting in less cognitive stimulation.
Justin S. Golub, an associate professor of otolaryngology at Columbia University Irving Medical Center, expressed his excitement about the study, calling it “truly unique” and “truly groundbreaking.” While smaller clinical trials have shown positive effects of hearing aids on cognition, this large-scale study provides further evidence of the benefits.
As the accessibility of hearing aids increases, it is hoped that more individuals at risk for dementia will seek hearing treatment to protect their cognitive health.