How do hearing and sight influence cognitive decline?
Opting for hearing aids and cataract surgery can make a big difference when it comes to slowing down cognitive decline.
Existing studies have pointed out that there is a link between the quality of a person’s hearing and their eye health and their exposure to cognitive decline.
For instance, one such study covered on Medical News Today suggested that poor hearing may correlate with a poor memory.
Another one proposed that we could detect Alzheimer’s disease by looking for tell-tale abnormalities in a person’s eyes.
Now, two new papers — each based on studies conducted by the same scientists from the University of Manchester in the United Kingdom — look at the evidence indicating that treating hearing loss and eyesight problems can slow down the development of cognitive decline.
One of the papers, published in the journal PLOS One, shows that people who have had surgery for cataract — which is condition that can lead to vision loss in the absence of a surgical intervention — have a slower cognitive decline rate.
The other paper, which is published in the Journal of the American Geriatrics Society, has reported similar findings about people who wear hearing aids.
“Age is one of the most important factors implicated in cognitive decline,” states Dr. Asri Maharani, one of the studies’ authors.
“We find that hearing and vision interventions may slow it down and perhaps prevent some cases of dementia, which is exciting — though we can’t say yet that this is a causal relationship.”
Dr. Asri Maharani
“But the beauty of this study is that we’re comparing the progress of the same individuals over time,” she notes.
Cataract surgery and hearing aids do help
In both of these studies, the researchers assessed the rate of cognitive decline by evaluating the participants’ episodic memory using word recall tests.
The scientists then compared the rates of cognitive function impairment before and after the participants started wearing hearing aids or underwent cataract surgery.
In the study that focused on the link between cataract surgery and cognitive health, the scientists worked with 2,068 participants who received this intervention between waves two and six of the English Longitudinal Study of Ageing, in 2002–2014.
These individuals’ results were then compared with those of an additional 3,636 participants who did not undergo cataract surgery.
In this case, the scientists found that participants who had received the corrective intervention had a 50 percent slower rate of cognitive decline than those who had not undergone surgery.
The study that focused on the link between hearing aids and cognitive decline rates found similar results. In this instance, the researchers worked with 2,040 participants recruited via the Health and Retirement Study of the Health Institute on Aging in 1996–2014.
For those who adopted hearing aids, the scientists found, the rate of cognitive decline was 75 percent slower following this intervention.
“These studies,” says Dr. Piers Dawes, involved in both studies, “underline just how important it is to overcome the barriers which deny people from accessing hearing and visual aids.”
It is important to ‘reduce stigma’
“It’s not really certain why hearing and visual problems have an impact on cognitive decline, but I’d guess that isolation, stigma, and the resultant lack of physical activity that are linked to hearing and vision problems might have something to do with it,” he says.
Dr. Dawes notes that some individuals may be too concerned about what others may think of them for wearing hearing aids, which could stop them from making this important change in their lives.
“[P]eople might not want to wear hearing aids because of stigma attached to wearing them, or they feel the amplification is not good enough or they’re not comfortable,” he suggests.
“Perhaps a way forward is adult screening to better identify hearing and vision problems and in the case of hearing loss, demedicalizing the whole process so treatment is done outside the clinical setting. That could reduce stigma,” Dr. Dawes further proposes.
The researcher also stresses the fact that hearing aids may become more attractive due to the fact that specialists are now developing some of them to have more than one function.
“Wearable hearing devices are coming on stream nowadays which might also be helpful. They not only assist your hearing, but give you access to the Internet and other services,” Dr. Dawes explains.