Challenges with Hearing Speech in Noise – an Early Sign of Dementia?

Do you ever find yourself struggling to follow conversations in a busy room full of chatter music and noise? While it is normal to have to ask people to repeat themselves when a room is noisy, it could also signal a hidden hearing loss. The World Health Organization (WHO), reports that up to 1.5 billion individuals worldwide suffer from some form of hearing impairment. While most forms of hearing loss can be identified by standard hearing tests, hidden hearing loss may elude detection for years. Now, according to a recent study, this may be more serious than commonly suspected, affecting the quality of life and even contributing to an increased risk of developing dementia later in life.

Hidden Hearing Loss

Most forms of hearing loss are sensorineural, which means tiny hair-like cells, responsible for sending audio signals to the brain become permanently damaged. Because sensorineural is the most common type of hearing loss, most hearing tests recorded on an audiogram, are designed to detect the loss of sensitivity across frequency ranges, such as the quietest pitch and tones you can detect.

Hidden hearing loss is characterized by an audiogram that reflects normal hearing sensitivity across all frequency ranges, but speech-in-noise tests reveal a deficit. When hidden hearing loss is present the stereocilia are healthy, showing a normal audiogram. This is because of cells in the inner ear that have sustained damage, instead, the auditory nerve fibers are damaged. This comprises the connection between the ears and the brain and the message the brain receives is incomplete.

Addressing Dementia

WHO estimates that worldwide, around 55 million people have dementia. One study estimates that with 4·6 million new cases of dementia occur annually with one new case every 7 seconds. Dementia is a neurogenerative disease that reduces functioning in at least 2 areas of cognitive functioning such as reasoning, ability to complete everyday tasks, or memory.  The victims of this disease are not just the patients but their families and loved ones who must provide around-the-clock care for their loved ones. There are several factors identified which reduce the risk of dementia – some modifiable and some not such as age and family history. Because there is currently no cure for this devastating disease, it’s important to do what we can to reduce the risk. Modifiable factors when done in conjunction reduce your risk such as regular cardiovascular exercise, eating healthy, staying social, and avoiding toxic air. One modifiable factor is addressing hearing loss.

Connecting Sudden Hearing Loss and Dementia

A recent study from the University of Oxford’s Nuffield Department of Population Health uncovered evidence that seniors who displayed symptoms of hidden hearing loss such as trouble hearing in busy restaurants on amongst street noise could risk a 91% increased risk of dementia later in life.

To come to this conclusion Stevenson and colleagues surveyed 82,000 men and women aged 60 years or older enrolled in the UK Biobank program. The participants were asked to identify spoken words amongst white noise. The test group was then divided into three separate groups depending on their ability to hear in noise: normal, insufficient, and poor speech-in-noise hearing. The study then tracked these participants over 11 years and found 1,285 participants developed or showed early signs of developing dementia. After modifying the testing scores to account for compounding factors the scientists found a risk which found that the “insufficient” group had a dementia risk of 61% and the “poor” group risk was 91%!

How Hidden Hearing Loss May Cause Dementia

The researchers did not specifically study why or how hidden hearing loss could affect the risk of dementia but they hypothesize that it may be due to many of hearing loss’ side effects. For instance, people who struggle to hear are much less likely to be social and thereforee less willing to try new things, stay active, and engaged. This can lead to chronic depression and anxiety which ultimately affects physical and mental health, as well as the quality of life.

Treating Hearing Loss

While hidden hearing loss is not as detectable on standard hearing exams, it is still treatable using hearing aids. To find out how you can use hearing aids to help reduce the risk of dementia schedule a hearing exam today.