Hearing Loss & Neuro Cognitive Disorders

It seems that almost every week more evidence emerges linking hearing loss with many other diseases and conditions. In particular, there has been a focus on the link between hearing loss, cognitive decline, Alzheimer’s and dementia. However, we have to be careful about what the link is and what evidence there is. So in honor of the recent  World Alzheimer’s Day, we wanted to take a closer look at how hearing loss and Alzheimer’s are connected.

The Research

Researchers from Johns Hopkins University and the National Institute on Aging have found that while the brain normally shrinks with age, this change is hastened or more pronounced in older adults with hearing loss, specifically un-treated hearing loss. Frank Lin, M.D., Ph.D., has been fascinated with untreated hearing loss and cognitive decline for quite some time and he has produced many papers that reference his studies and his findings.

He and his colleagues studied the differences in brain changes over time (shrinkage) based on data from the Baltimore Longitudinal Study of Aging. This study involved 126 patients who were studied over the course of 10 years. The study measured the width of the brain tissue for each subject and found that the subjects who had entered the study with hearing loss exhibited accelerated rates of brain atrophy when compared to those subjects who had normal hearing.

The Results

Let's delve deeper into the results for the people with hearing loss:

  1. Accelerated rates of brain shrinkage
  2. Loss over an additional 1 cubic centimer of brain tissue each year compared to those with normal hearing
  3. More shrinkage in superior, middle and inferior temporal gyri (structures of the brain responsible for processing sound and speech)

If you consider the results in reference to the shrinkage in the areas that make up auditory processing, it makes sense. If those areas are deprived of proper input because of hearing loss, it appears they wither. Gives a whole new meaning to use it or lose it.  We know that those areas don’t just work alone, so the impact there may contribute to overall degradation of the brain. It also should be noted that the middle and inferior temporal gyri also help with memory and sensory integration. They are also involved with early stages of Alzheimer’s. 

Correlation Only!

The findings of this research indicate that hearing loss and Alzheimer’s are correlated, and it's important that you realize what that means. When something is found to have a correlated link, it means that there is evidence that there is a possible strong association between them. It does not necessarily mean that one thing causes another. Until research definitively proves causation, we are just talking association. 

However, with what we know about the effects of untreated hearing loss and cognition, it does add to the urgency to treating hearing loss early. It is more than just possible that the underlying hearing loss is contributing to the brain changes being seen. This really means that hearing loss should be treated at the earliest possible opportunity. 

Regular hearing checks

So what conclusions can we take from this and other study evidence?  Having your hearing checked and treated early could mean better long-term brain performance and overall, better long-term health and wellness. This we know. Having your hearing checked and getting early treatment could lead to a lesser chance of Alzheimer’s and dementia. This we think from the available evidence, but it is not a sure thing. No matter what, there is absolutely reams of evidence that treating hearing loss early is the best thing to do, leads to better outcomes, and contributes to active and healthy aging. 

Have you gotten your hearing checked lately? It might help you more than you think. If you would like a hearing test in the Cleveland area, why don't you call us at 1-440-248-4790 or book your appointment online now.