Source: Department of Neurology, Shanghai Children’s Hospital
Author: Zhang Yuanfeng
In outpatient clinics, it is common for parents to bring their children for consultation, anxiously describing their child’s symptoms: blinking, nose twitching, lip pursing, throat clearing, shoulder shaking, vocalizations, and more. They anxiously inquire whether their child is having seizures, if there is a problem with their brain, or if it is just a bad habit. In reality, these children are suffering from a disease collectively known as tic disorders.
Tic disorders are a group of syndromes characterized by involuntary, repetitive, sudden, rapid, and non-rhythmic motor and/or vocal tics that primarily manifest during childhood or adolescence. They are relatively common in clinical practice. It has been reported that transient tic disorders have a history in approximately 5%-20% of school-age children, while the prevalence of chronic tic disorders in children and adolescents is around 1%-2%, and Tourette syndrome has a prevalence of 0.1%-0.5%. Tic disorders are more commonly observed in boys.
The exact etiology of tic disorders is not fully understood, but it is believed to result from the interaction of genetic factors, neurophysiology, neurochemistry, and environmental factors. Tics are involuntary but can be temporarily suppressed through conscious effort. There are several types of tics, including:
- Simple motor tics: These primarily involve eye blinking, nose twitching, and other similar movements.
- Complex motor tics: These involve more coordinated actions such as lip biting, poking, spinning, jumping, imitating others’ actions, or making inappropriate gestures.
- Simple vocal tics: These include sniffing, throat clearing, or barking-like sounds.
- Complex vocal tics: These involve the repetition of specific words or phrases, echolalia (repeating one’s or others’ words or phrases), or the use of vulgar language.
All forms of tics can be exacerbated by stress, anxiety, fatigue, excitement, or fever, and can be alleviated by relaxation or intense engagement in activities. Tics typically disappear during sleep.
Tic disorders are often mistaken for related organ diseases. For example, eye blinking is often misdiagnosed as conjunctivitis, leading parents to use eye drops for months without improvement. Nose twitching or sniffing may be misdiagnosed and treated as allergic rhinitis, resulting in prolonged medication use and expenses. In fact, many of these children are displaying symptoms of tic disorders. Therefore, both parents and clinicians should be aware of the possibility of tic disorders in such children. When the treatment outcome is unsatisfactory and organic diseases related to the ear, nose, and throat have been ruled out, prompt referral to the Department of Neurology is necessary to avoid further delay in diagnosis.
Currently, there is a lack of specific diagnostic criteria for tic disorders, and the diagnosis relies primarily on clinical description. The purpose of examinations is mainly to rule out other diseases. For example, blood tests may be conducted to exclude rheumatic chorea, neurophysiological examinations to exclude myoclonic epilepsy, and cranial imaging to exclude organic brain lesions (e.g., Wilson’s disease).
Approximately half of the affected children have one or more concurrent psychiatric disorders, including attention-deficit/hyperactivity disorder (ADHD), learning difficulties, obsessive-compulsive disorder (OCD), sleep disorders, mood disorders, self-harm behaviors, conduct disorders, and explosive outbursts.
Regarding treatment, for children with mild symptoms that do not affect their learning or daily life, medication is not recommended. Instead, psychological and behavioral therapies should be the main approach. For children with
moderate to severe symptoms that interfere with daily activities, learning, or social interactions, medication treatment should be considered when psychological and behavioral therapies alone are insufficient. The medication should be administered at an appropriate dosage and for a suitable duration, without premature switching or discontinuation. Concurrent psychiatric disorders should also be addressed. Psychological and behavioral therapy is a necessary supplement to medication treatment. It helps children and parents gain a proper understanding of the disorder, avoid excessive focus on the tic symptoms, and handle encountered problems (such as teasing by classmates). It is important to eliminate various factors in the environment that may negatively affect the child’s symptoms, improve the child’s emotional well-being, and enhance their self-confidence. Furthermore, parents and teachers should be helped to understand the nature and characteristics of the disorder, emphasizing that it is a medical condition and not the child’s intentional behavior, in order to gain their cooperation and support for proper education and patient assistance.
In addition, it is important to establish a balanced lifestyle for affected children, avoiding excessive excitement, stress, fatigue, and fever, as these factors can trigger or worsen the disorder. Engaging in rhythmic physical activities can also be beneficial. It is advised to avoid certain foods in the child’s diet, such as puffed snacks, carbonated beverages, coffee, and tea, as they may aggravate the symptoms.
The prognosis for children with tic disorders is generally good. Only a small number of cases may experience prolonged symptoms that significantly impact their social functioning, requiring long-term medication treatment to control the symptoms. Most children experience a gradual improvement in symptoms during late adolescence, but for some individuals, the symptoms may persist into adulthood or even throughout their lives.