May is Better Hearing & Speech Month!

Parkinson’s disease (PD) and hearing loss are two seemingly unrelated conditions affecting millions of people worldwide. Until recently, little has been known about the interplay of these conditions, but emerging research suggests a possible connection between the two.

Here are the potential causes, signs, and treatment options for hearing loss with Parkinson’s disease.

The Stats on PD & Hearing Impairment

Research exploring the connection between PD and hearing loss is evolving, but studies have revealed intriguing correlations.

Recent data suggests individuals with Parkinson’s may have a higher incidence of hearing loss compared to those without the disease. For example, a 2017 study found hearing impairment was more prevalent in people with Parkinson’s than in age-matched controls, indicating a possible link.

Further, a 2020 study indicates age-related hearing loss combined with Parkinson’s neuropathology may put people with PD at a higher risk of experiencing hearing impairment.

These findings suggest hearing loss might not only be a comorbid condition but potentially related to the neurodegenerative processes characterizing Parkinson’s disease.

APD vs. Hearing Loss

Auditory Processing Disorder (APD) and hearing loss are two distinct auditory issues affecting how sound is perceived and processed, differing in their underlying causes and effects on communication.

It’s important to note the difference as some hearing impairments experienced by people with PD may be a result of APD and not hearing loss. Diagnosing between the two can be a challenge, but there are key differences to consider.

Hearing Loss

Hearing loss refers to a reduction in the ability to hear sounds in one or both ears. Many factors, including age, exposure to loud noise, infections, genetic predispositions, and damage to the ear structures, can cause it.

The primary issue in hearing loss is diminished sensitivity to sound levels or specific frequencies, making it hard to hear soft sounds or those within specific pitch ranges.

APD

On the other hand, ADP occurs when the brain has difficulty processing the sounds the ears hear. This means that even if the sound is heard at a normal volume and clarity, the person with APD may struggle to interpret or make sense of the sound.

APD affects how sound is decoded, interpreted, and understood, despite normal hearing ability. People with APD may have trouble understanding speech in noisy environments, distinguishing similar sounds, or quickly processing the information they hear.

Because hearing loss results from damage to the ear structure and APD is a neurological condition, it’s theorized that APD in people with Parkinson’s could be connected to the neurological effects of PD. More research is needed to truly understand the differences and impacts.

Potential Causes of Hearing Loss in People with PD

More research is needed to clarify precisely how Parkinson’s impacts hearing loss, but there are several working theories as to the cause and effect of these conditions.

Neurological Deterioration

Parkinson’s disease is characterized by the degeneration of nerve cells in the brain, particularly those producing dopamine, a neurotransmitter vital for coordinating movement and other bodily functions.

Researchers hypothesize the same process of neurodegeneration could also affect the auditory pathways. The auditory system is complex, relying on precise neural transmissions.

Any disruption in these pathways, possibly due to dopamine depletion, could impair hearing.

Shared Risk Factors

Both hearing loss and Parkinson’s disease share certain risk factors. These include age, exposure to ototoxic medications (those causing damage to the sensory cells critical for hearing and balance), and environmental factors, such as noise exposure.

It’s also noted that oxidative stress—a damaging cellular process linked with PD—might also play a role in hearing loss. This overlap suggests the two conditions could develop as part of the aging process or as a response to shared environmental stresses.

Medication Effects

Some medications used to manage Parkinson’s symptoms can have ototoxic effects, meaning they can damage the auditory system.

For example, specific dopamine agonists and anticholinergic drugs can cause auditory hallucinations or tinnitus, which may exacerbate or masquerade as hearing loss.

Signs of Hearing Loss with PD

People living with Parkinson’s can experience hearing impairment in several ways. Here are a few signs to look out for.

Auditory Hallucinations

In PD, changes in brain function can sometimes manifest as auditory hallucinations.

These are sounds a person hears despite them not being present in the environment. For someone with hearing loss, these hallucinations could be initially mistaken for issues with auditory perception.

Tinnitus

Tinnitus, often described as ringing in the ears, is a common symptom associated with hearing loss and Parkinson’s disease.

This symptom can be particularly distressing as it may further isolate individuals from engaging in conversations and social interactions. This may worsen the feelings of loneliness or depression commonly associated with both conditions.

Reduced Speech Perception

People with Parkinson’s often experience changes in speech, including a softer voice and less precise articulation. When coupled with hearing loss, these changes can make it even harder for individuals to communicate, leading to significant social and emotional challenges.

Treating Hearing Loss with Parkinson’s

Hearing loss and impairment can severely impact people living with PD. Fortunately, there are a range of effective tactics for mitigation and treatment.

Hearing Evaluations

Regular hearing evaluations should be part of the management plan for people with Parkinson’s disease, especially since hearing loss can sometimes be subtle or gradually worsen without obvious symptoms.

Early identification through audiological assessments can help in implementing strategies to improve quality of life and communication.

Assistive Listening Devices

For those with hearing loss, various assistive listening devices such as hearing aids or cochlear implants may be beneficial.

These devices amplify sounds, making it easier for individuals to engage in conversations and stay connected with their surroundings.

People living with Parkinson’s may need more frequent adjustments to the devices due to the progressive nature of both conditions.

Speech Therapy

Speech therapy can be invaluable for individuals with Parkinson’s and hearing loss. It can help improve articulation and voice volume, making speech clearer and easier to understand for others, especially in noisy environments.

Additionally, speech therapists can provide strategies to help people cope with tinnitus and auditory hallucinations.

Integrative Care

Managing these overlapping conditions necessitates a comprehensive approach involving neurologists, audiologists, and therapists working together to create a personalized care plan.

This integrative approach ensures that treatments for Parkinson’s do not exacerbate hearing issues and any strategies for managing hearing loss are tailored to accommodate the specific challenges faced by those with Parkinson’s.

Hearing Loss & PD: An Evolving Area of Research

The connection between hearing loss and Parkinson’s disease is an emerging area of research highlighting the complex, intertwined nature of neurological health.

As we begin to better understand these links, the development of more nuanced treatments addressing both hearing health and motor function in people with Parkinson’s seems both promising and essential!

This Hearing & Speech Month, we’re hosting Dr Julia Nicholls, Speech Language Pathologist, to discuss how speech therapy can improve the quality of life for people living with Parkinson’s.

Register for this May 10th LTP here. We’ll also send a recording of the event afterward for those who can’t attend!