Tics and Tourette’s Syndrome
Tics are movements or vocalizations which are semi-involuntary in response to an irresistible urge. They can be described as scratching an itch: tics can be suppressed but only momentarily.
Tics range widely in manifestation, from simple motor tics such as blinking to complex vocal tics such as repeating words. Tourette’s syndrome refers to a neurodevelopmental syndrome beginning in childhood and consisting of both motor and vocal tics. Many children outgrow Tourette’s syndrome but a significant proportion continue to have tics. Medications and cognitive behavioral therapy can help.
Tics are semi-involuntary, meaning that the patients know they are making the movements or vocalizations themselves but they feel absolutely compelled to do so. Motor tics can include blinking, facial grimaces, neck, arm or leg movements, tapping, clenching, and sometimes more complex movements such as combinations of movements, or touching a particular spot a particular number of times. Vocal tics can include sniffing, coughing, clearing one’s throat, making animal noises, repeating syllables, and repeating words. While lay people assume that Tourette’s syndrome is equivalent to shouting out obscenities, only about 5% of patients with Tourette’s experience this.
Tourette’s syndrome is a clinical diagnosis, meaning that it is based on the symptoms and signs on examination. Various rating scales can be employed to quantify the severity of the condition, including the Yale Global Tic Severity Scale, which assesses the frequency, complexity and number of tics, as well as the degree to which they interfere with daily life. There are no blood tests for Tourette’s, nor MRI findings, but research is being done on genetic etiologies of Tourette’s syndrome since a family history is common and there is often overlap with Attention Deficit Hyperactivity Disorder (ADHD) and Obsessive Compulsive Disorder (OCD).
A holistic approach to a patient with tics is key, because tics have a very strong relationship with psychosocial issues in the patient’s life. For example, tics may increase during times of excitement such as the beginning and end of the school year, or may manifest more severely when there is untreated anxiety. Thus, addressing the underlying cause of tics is the most successful way to manage tics, rather than simply using tic suppressing medications in isolation. Many patients may benefit from psychotherapy, either cognitive behavioral intervention for tics (CBIT) or therapy for underlying anxiety or OCD. When non-pharmacological interventions do not result in satisfactory control of tics, medication options range from mild to very potent.
The intensity of the medication efficacy (and side effects) should be matched to the severity of the condition, based on a validated rating scale such as the Yale Global Tic Severity Scale. Mild medications include alpha-agonists such as clonidine and guanfacine, which is also used as a non-stimulant medication for ADD. Moderate medications include topiramate, which is an anti-seizure medication that has benefit for tics. Stronger medications include the antipsychotics such as aripiprazole, ziprasidone or clozapine; and the dopamine-depleting agent tetrabenazine. Deep brain stimulation (DBS) surgery is under investigation for treatment of severe, medication-refractory Tourette’s syndrome, with many case series reporting benefit in tic reduction.