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Anxiety DisorderAnxiety Disorder

Anxiety or fear is a basic emotion and a normal part of life. While anxiety involves worry about future events, fear is a reaction to current danger. One might feel anxious when giving a public speech, taking an examination, or encountering a sudden change. It is a normal reaction to stress and danger. However, when the anxiety or fear becomes excessive and unreasonable, causing subjective distress or objective impairments in daily functioning, it becomes a disorder.

Anxiety or fear is a normal part of childhood development. It is common for infants to show fear of loud noises and strangers. Fears of thunder, animals, insects, darkness, monsters, separation are often noted among toddlers and preschoolers. School-age children might worry about going to school and examinations, and relationship with peers. Anxiety disorders are different from the developmentally normal fear or anxiety by being excessive, persistent, or extending beyond the developmentally appropriate periods. While normal anxiety alerts an individual to cope with the danger, pathological anxiety often occurs in the absence of real threat.

Anxiety disorders commonly found in children:

Social Anxiety Disorder (Social Phobia):

  • Show intense fear when facing unfamiliar people, and appear uneasy in social gatherings or become nervous when expected to start conversations with others.
  • Show marked fear when they become the centre of attention, or when there is possible scrutiny by others, such as performing on stage or being called on in class.

Separation Anxiety Disorder:

  • Show developmentally inappropriate and excessive anxiety when being separated from parents or caregivers.
  • Often worry about losing their parents or about any possible harm that might come to them, resulting in reluctance of being alone, calling parents who are away for assurance, or even school refusal.

Selective Mutism:

  • Consistently fail to speak at specific social situations (such as in school or social gatherings), despite speaking normally in other situations in which they feel safe and comfortable (usually at home).

Generalized Anxiety Disorder:

  • Show excessive and uncontrollable worry about a number of everyday matters, e.g., academic results, peer relationship, family issues, even the idea of potential accidents or disasters.
  • May present with irritability, concentration difficulty, or somatic complaints such as sleeping problems, muscle tension etc.

Specific Phobia:

  • Have an extreme and irrational fear of a specific object or situation, e.g. an animal, insect, injection, the sight of blood, height or darkness, etc.
  • The feared objects or situations are usually avoided or endured with intense distress.

Anxiety disorders often cause significant interference in multiple aspects of life. It affects children’s social relationship, daily routines, or academic functioning. Children suffering from anxiety disorders often have negative thinking style and maladaptive behavioural pattern. They often overestimate the danger of objects or situations, and often react by avoidance coping. Some children may also present with temper problems. Physiological illnesses and psychosomatic complaints such as headache, stomachache, sweating, and muscle pain are also frequently noted.

The irrational fears and avoidance behaviour often hinder children’s participation in social activities and friendship development, and, affect their performance and involvement in school work, everyday contact with people and daily functioning. Untreated anxiety disorder may persist into adulthood and lead to depression and substance abuse.

Adults with anxiety disorders may recognize that their fears or anxiety are excessive or unreasonable. However, such awareness may be absent in children. It may be difficult for children to explain their fears and worries verbally, particularly for younger ones. It is therefore important for parents to pay due regard to signs and symptoms of anxiety problems. Changes in behaviour or increase of tantrums are common flags of stress and anxiety in children. Some children may also develop some nervous habits. Other common signs include change in sleep or appetite pattern, or somatic complaints.

Anxiety disorders are a common form of disorders in children, with a prevalence rate of approximately 8 to 10% in western countries. In general, girls are more easily affected than boys. The local prevalence estimates and gender differences are largely compatible with those reported in Western countries.

The exact causes and mechanisms of anxiety disorders are not fully known. However, research suggests that biological, psychological and environmental factors interplay in the development of anxiety disorders.

Biological factor:

Anxiety disorders may run in families and genetic factors are believed to predispose some individuals to anxiety disorders. Imaging studies also indicate that people with anxiety disorders have atypical activities in specific areas of the brain, including the prefrontal cortex, limbic system, amygdala and thalamus. Besides, abnormal levels of neurotransmitters (chemicals in the brain for transmitting information between nerve cells) also play a part in the causes of anxiety.

Psychological factor:

Psychological causes of fears and worries in children with anxiety disorders may include negative thinking, reluctance of making attempt, perfectionistic thinking, and fear of making mistakes. These thinking styles often result in apprehensive expectations when encountering stress and difficulties.

Environmental factor:

External sources of anxiety and stress in children may include academic difficulties, conflict with friends, family problems etc. Parents’ attitudes and reactions may also affect the development and maintenance of anxiety problems in children. Parenting styles such as over-protectiveness may exacerbate the problem. Sometimes parents may reinforce children’s anxious or avoidance behaviour unintentionally, such as giving excessive soothing. Children may also “learn” the anxious behaviour from parents through observation and modeling.

Comorbidities of multiple anxiety disorders or with other emotional and behavioural problems are commonly found among children with anxiety disorders. Compared to the normally developing peers, children with anxiety disorders are more likely to have comorbid depressive moods, lower positive affectivity, and more oppositional problems.

Choices of treatment depends on the type and severity of the anxiety problem. While psychological intervention is commonly used in the treatment of childhood anxiety, children who are older and with more severe symptoms may consider pharmacological treatment.

  1. Psychological treatment:


    Research studies have identified cognitive behavioural therapy (CBT) as a highly effective treatment for anxiety disorders. There are three major treatment components in CBT — thought, behaviour and physical response.

    • Thought — Children are guided to identify, challenge and change their irrational beliefs (e.g. “If I am not perfect I am a failure”). As such approach demands certain level of cognitive ability and maturity, preschool or early primary school children are sometimes taught to use positive thoughts to replace their negative and irrational thoughts directly (e.g. “Even if I can’t answer the question, I won’t be punished by teacher.”).
    • Behaviour — Exposure to the fearful objects or situations may allow children to experience the harmless or uneventful outcome of exposure. It is usually done in a graded manner, with the exposure exercise starts with a mildly provoking situation, and gradually progressing to a more challenging and provoking situation.
    • Physical response — Relaxation exercises (such as breathing and muscular relaxation) are usually part of anxiety treatment and management to help children cope with the physiological symptoms of anxiety.


    Parents play an important role in the treatment, by identifying responses that may reinforce or maintain children’s anxiety problem, and by supporting them to face their fear and anxiety. Young children need parents’ close involvement in implementing treatment techniques. For older children or adolescents, discussions with them on the extent of parent involvement at the beginning of the therapy may be necessary.

  2. Medication:

    Selective serotonin reuptake inhibitors (SSRI), selective noradrenaline reuptake inhibitors (SNRI) and tricyclic antidepressant are commonly used medication to help relieve the anxiety symptoms. On the other hand, benzodiazephine may be used to reduce the physical symptoms (such as muscle tension). Some medications are fast-acting while others may take a few weeks to experience their full effect. The rationale for selection of a particular type of medication, possible side effects, and the availability of other treatment options should be discussed with the parents. It is important to note that change of dosage or type of medication, or discontinuation of medication should be done only under doctor’s supervision.

  • Child Assessment Service of the Department of Health offers behavioural and developmental assessment for children, and interim support in the form of information workshops and treatment groups.
  • Child and Adolescent Mental Health Services of Hospital Authority provide medical and psychological treatments for children with anxiety disorders.
  • Educational psychologists offer support at school to teachers and children in need.
  • Some non-governmental organizations provide child training and parent support activities.

Current research evidence is still inconclusive. But undoubtedly, if children with excessive amount of anxiety are left without treatment, the condition is likely to persist or exacerbate. In contrast, with timely and appropriate treatment, the prognosis is generally good.

  • American Psychiatric Association (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC: Author.
  • Dougherty, L. R., Tolep, M. R., Bufferd, S. J., Olino, T.M., Dyson, M., Traditi, J., Rose, S., Carlson, G. A., & Klein, D. N. (2013). Preschool anxiety disorders: Comprehensive assessment of clinical, demographic, temperamental, familial, and life stress correlates. Journal of Clinical Child & Adolescent Psychology, 42(5), 577-589.
  • Gullone, E. (2000). The development of fear: A century of research. Clinical Psychology Review, 20(4), 429-451.
  • Huberty, T. J. (2012). Anxiety and depression in children and adolescent: Assessment, intervention, and prevention. New York: Springer-Verlag.