Facial Masking in Parkinson's Disease

Facial masking, also called masked facies or hypomimia, is the loss of facial expression most commonly associated with Parkinson's disease. The condition gives the affected person a fixed, mask-like expression.

There may be several causes of facial masking, including a psychiatric disorder like schizophrenia that may limit affect and expression, or medication that may lead to a similar response. With Parkinson's disease, the facial masking is typically caused by a progressive loss of motor control.

This article explains why Parkinson's disease may lead to facial masking and how it is treated. It will help you to learn more about symptoms that sometimes make it harder to interact with loved ones with the condition.

What Is Facial Masking?

Facial masking affects both voluntary facial movements (such as a smile) and involuntary ones (such as occurs when a person is startled). Humans communicate not only through words but through subtle, fast-moving changes in facial expression. An expressionless face, therefore, limits the connection between people.

When you aren't able to convey emotions with facial expression, it's a disadvantage because others may misinterpret words, or be uncertain and confused when expressions don't match with words.

The Unified Parkinson’s Disease Rating Scale (UPDRS) section for facial expression includes a scale to help healthcare providers track the progression of the disorder.

The UPDRS scale values include:

• 0 - Normal facial expression
• 1 - Slight hypomimia, poker-faced
• 2 - Slight but definitely abnormal loss of facial movement
• 3 - Moderate loss that is present most of the time
• 4 - Marked loss that is present most of the time

It's important to remember that some people living with Parkinson's disease also find it difficult to identify emotion in other people's faces. The inability to recognize sadness, fear, and other emotions also creates an interpersonal barrier and affects quality of life.

Masked Face and Parkinson's

Facial masking is symptomatic of the degenerative nature of Parkinson's disease. The hallmark feature of the disease is the progressive loss of motor control.

This loss of control affects major limbs, but it also affects the finer muscle movement of the hands, mouth, tongue, and face. Facial masking affects some 70% of people living with a Parkinson's diagnosis.

Therapy for Facial Masking

Facial expression matters. Research has shown that quality of life is better in persons with Parkinson's who have undergone therapy to improve facial control than those who have not.

Therapy typically demands an intensive, therapist-guided program which would initially focus on broader facial movements, such as lifting the eyebrows, stretching the mouth, or puckering the face.

One technique called the Lee Silverman voice treatment (LSVT) is used by some to help people with Parkinson's speak louder and more clearly. It employs articulation exercises that are similar to stage acting techniques, in which a person is taught to project and enact "speaking behavior" by:

• Straightening the posture
• Looking a person directly in the face
• Keeping the chin up
• Taking deep breaths before speaking
• Focusing on big, loud sounds and slow, short phrases

The LSVT technique and similar rehabilitative approaches (such as choir singing or voice amplification) have proven valuable in helping people living with Parkinson's to isolate and control specific facial muscles more effectively when communicating in groups or one-on-one.

Facial Masking and Medication

Some medications have been found to improve symptoms of a masked face with Parkinson's disease. They include levodopa (L-dopa), a drug often used to replace dopamine. Researchers have demonstrated a link between facial masking symptoms and low dopamine responses.

Because levodopa alone leads to side effects of nausea and vomiting, it's usually given as a combined drug with carbidopa, such as Sinemet or Parcopa.

For some people, a surgically implanted device in the abdomen will deliver Duopa, a carbidopa-levodopa combination that is continually administered and reduces what's known as "off time," when drug benefits are reduced.

Other medications used to treat facial masking include:

• Stalevo, adding entacapone to the carbidopa-levodopa mix
• Mirapex (pramipexole), a dopamine agonist
• Requip (ropinirole), also an agonist
• Neupro (rotigotine) patches and APOKYN (apomorphine hydrochloride) injections

Other drugs, such as catechol-o-methyl transferase (COMT) inhibitors and monoamine oxidase type B (MAO-B) inhibitors, may be used to boost the effects of levodopa.