Persistent (Chronic) Motor Or Vocal Tic Disorder
Overview
Persistent (chronic) motor or vocal tic disorder is one of five tic disorders in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). PMVT, sometimes called chronic tic disorder or chronic motor tic disorder, has an onset before age 18. Symptoms must be present nearly every day for over a year and must not be caused by other health conditions, medications, or substance use. One defining characteristic of persistent motor or vocal tic disorder, or PMVT is that someone with this disorder can have either motor or vocal tics but not both during the course of the illness. Tics are sudden, uncontrollable, spastic movements or verbal outbursts. Persistent motor or vocal tic disorder is thought to be a forme fruste of Tourette syndrome (TS), meaning it’s a milder form of the syndrome. If both vocal and motor tics appear, a diagnosis of Tourette's disorder1 may be made.
Individuals with persistent (chronic) motor or vocal tic disorder and other tic disorders tend to have the same tics, although they can vary in intensity and frequency. Tics associated with this tic disorder can occur multiple times an hour, fade, and barely appear for months. Still, they must be present for more than one year to be officially diagnosed. Some tics are simple, like a brief vocalization or movement; others are complex, which may be a combination of simple tics. While simple tics do not appear to have any social meaning, complex tics may appear as recognizable gestures or words and could seem intentional.
Symptoms
The primary symptom of PMVT is the presence of either vocal or motor tics nearly every day for more than a year. These symptoms may be chronic, such as chronic motor tics. A motor tic impacts the body, whereas a vocal tic impacts the voice. Chronic tics are often considered life long. People with persistent (chronic) motor or vocal tic disorder have either vocal (verbal tic) tics or motor tics, but not both.
Vocal
Some examples of vocal tics that people with persistent (chronic) motor or vocal tic disorder may experience include:
- Grunting
- Barking
- Snorting
- Coughing
- Sniffing
- Throat clearing
- Repeating others
- Repeating words
- Humming
- Uttering inappropriate words
- Hissing
- Yelling
Motor
People with motor tics may perceive that their tics are a response to an inner urge and may have abnormal sensations in the area of the tic before it occurs. Motor ticks can also be simple or complex.
Motor tics often involve only one muscle group or body part. In contrast, complex tics can involve a series of movements, including multiple muscle groups or a combination of many simple motor tics. Complex motor tics may appear to others as purposeful movements, but they can significantly interfere with everyday life.
Motor tics that someone with PMVT can have include:
- Jerking
- Blinking
- Grimacing
- Head banging
- Shoulder shrugging
- Foot tapping
- Imitating someone else’s movements
- Lip biting
- Nose wrinkling
- Frowning
- Head turning
- Sticking out the tongue
- Squatting
- Kicking
- Jumping
- Hopping
- Rocking back and forth
Tics are not voluntary and may be more noticeable when the person is relaxing. Certain factors may worsen tics, including stress, excitement, sleep deprivation, caffeine, and heat. They rarely occur during sleep, though they can. Engaging in a task or activity can lessen the frequency or severity of tics. Some people with persistent vocal motor tic disorder can suppress their tics for a few seconds or minutes, while others may have the urge to perform them.
Causes
Tics, like those that appear in persistent (chronic) motor or vocal tic disorder, are likely caused by a combination of factors, including genes, the environment, and dysfunctional connections between the parts of the brain that control movement.
Recent studies have found that rates of persistent (chronic) motor or vocal tic disorderwere substantially higher in first-degree relatives compared to the general population. People with persistent (chronic) motor or vocal tic disorder are also at risk for developing additional psychiatric comorbidities,2 including obsessive-compulsive disorder (OCD),3 attention-deficit hyperactivity disorder (ADHD),4 general anxiety disorder (GAD),5 mood disorders, and disruptive behavior disorders.
Treatments
There are multiple treatment options available for PMVT and comorbid conditions like obsessive-compulsive disorder and attention-deficit hyperactivity disorder, including the following.
Therapy
Habit reversal training (HRT) is the primary type of therapy used to treat PMVT. It often consists of three steps. The first step is awareness training, which guides individuals to notice the sensations they experience before the tic occurs. Next, the therapist helps the client identify a competing response for each tic. Finally, the individual focuses intensely on replacing the tic with the competing response.
Comprehensive behavioral intervention for tics (CBIT) is a highly structured form of HRT that can be specialized to the needs of each client. This type of HRT is similar but does have some key differences. It also consists of three parts: familiarizing the patient with their tic symptoms, developing competing responses to use when urges or tic symptoms occur, and adjusting daily activities to reduce the likelihood of symptoms. CBIT also includes relaxation training and psychoeducation intervention to help clients cope with outside factors that can incite a tic or affect tic severity, such as obsessive-compulsive disorder.
Medication
Though there are no medications FDA approved to treat persistent (chronic) motor or vocal tic disorder, there are medications that are used to treat some of the symptoms of PMVT such as tics.
Medication may be necessary if tics interfere with someone’s quality of life. Multiple medications can be effective at treating PMVT and other tic disorders.
Only three medications have FDA approval for the suppression of Tourette syndrome-related tics; these are: haloperidol, pimozide, and aripiprazole.
However a healthcare professional may prescribe one of these other medications to treat tics:
- Clonidine
- Guanfacine
- Botulinum toxin A: This injectable medication can relax or stop muscles from moving, which can reduce tics and tic-related issues.
Consult a medical doctor before starting, changing, or stopping a medication for any condition. The information in this article is not a replacement for medical advice or diagnosis.
Self-care
While tics cannot be cured, there are some ways to lessen their impact, including:
- Finding ways to forget about the urge
- Avoiding stressful situations as much as possible
- Getting enough sleep
- Avoiding drawing attention to the tic
Avoiding stress may not be possible in every situation, but some self-care techniques you can use to deal with stress include the following:
- Getting at least 30 minutes of exercise a day—Even 30 minutes of walking, broken into two 15-minute sessions may be helpful
- Eating healthy, regular meals
- Staying hydrated
- Setting goals and priorities—Decide what you can do now and what can wait, and learn to say “no” if you begin to sense you’re taking on heavy duties
- Identifying negative or unhelpful thoughts and challenging them
- Doing a relaxing activity, like yoga, journaling, or breathing exercises
- Staying connected to friends and family and reaching out for help
Resources
If you’re experiencing motor or vocal tics and want to learn more about HRT or CBIT, an online therapy platform like BetterHelp may be helpful. Some people with tics may be self-conscious about them, and attending in-person therapy may cause additional stress. With online therapy, you can talk to a therapist online and learn more about possible treatments from the comfort of your home via phone, video, or live chat sessions.
Support for persistent (chronic) motor or vocal tic disorder
The International Parkinson and Movement Disorder Society offers handouts about multiple movement disorders, including tic disorders. The Tourette Association of America offers in-person support groups around the country for people with Tourette and tic disorders. There are also online support groups available to people in the Tourette and Tic disorders community.
Research
Some recent research proposes that PMVT is a milder form of Tourette syndrome. This study found that those with PMVT had strong family histories and lower tic severity, later age of onset, and lower or similar rates of psychiatric comorbidities than people with Tourette syndrome.
As noted above, OCD and ADHD are more prevalent in people with persistent (chronic) motor or vocal tic disorder. Although the prevalence of these two conditions is lower in PMVT than with Tourette syndrome, they are still significantly higher than in the general population. Researchers believe this connection may show shared genetic ties between these conditions and concluded that PMVT and Tourette's syndrome are more similar than they are different. Some believe they may be the same condition, with Tourette being the most severe version.
Another recent study looked at the effectiveness of online support groups for people with tic disorders and Tourette syndrome and found that online communities had a positive impact on the well-being of people with these conditions and their families. Online communities provide a place where people with these conditions can belong to a community that reduces their social isolation and helps them find acceptance.
Statistics
Below are several statistics about persistent chronic motor or vocal tic disorder:
- Although PMVT is believed to be more common than Tourette syndrome, its prevalence is unknown. The CDC estimates that persistent tic disorders like PMVT and Tourette syndrome affect about 1.4 million people in the US.
- People with PMVT have high rates of psychiatric comorbidities. About 20% of people with PMVT also have OCD, and 60% also have ADHD. The rates of OCD and ADHD in people with PMVT are approximately ten times higher than in the general population.
- Tics generally increase in severity from childhood and peak between ages 10 and 12. Most tics disappear on their own, but in about 1% of children, tics persist into adulthood.
- Tics are more likely to affect boys than girls by as much as 4:1.
- According to the CDC, behavioral therapy may reduce the severity of tics.