ICD-11 Criteria for Generalised Anxiety Disorder (GAD)

Foundation URI:  http://id.who.int/icd/entity/1712535455

Description

Generalised anxiety disorder is characterised by marked symptoms of anxiety that persist for at least several months, for more days than not, manifested by either general apprehension (i.e. ‘free-floating anxiety’) or excessive worry focused on multiple everyday events, most often concerning family, health, finances, and school or work, together with additional symptoms such as muscular tension or motor restlessness, sympathetic autonomic over-activity, subjective experience of nervousness, difficulty maintaining concentration, irritability, or sleep disturbance. The symptoms result in significant distress or significant impairment in personal, family, social, educational, occupational, or other important areas of functioning. The symptoms are not a manifestation of another health condition and are not due to the effects of a substance or medication on the central nervous system.

Diagnostic Requirements

Essential (Required) Features:

• Marked symptoms of anxiety manifested by either:
  • General apprehensiveness that is not restricted to any particular environmental circumstance (i.e., ‘free-floating anxiety’); or
  • Excessive worry (apprehensive expectation) about negative events occurring in several different aspects of everyday life (e.g., work, finances, health, family).
• Anxiety and general apprehensiveness or worry are accompanied by additional characteristic symptoms, such as:
  • Muscle tension or motor restlessness.
  • Sympathetic autonomic overactivity as evidenced by frequent gastrointestinal symptoms such as nausea and/or abdominal distress, heart palpitations, sweating, trembling, shaking, and/or dry mouth.
  • Subjective experience of nervousness, restlessness, or being ‘on edge’.
  • Difficulty concentrating.
  • Irritability.
  • Sleep disturbances (difficulty falling or staying asleep, or restless, unsatisfying sleep).
• The symptoms are not transient and persist for at least several months, for more days than not.
• The symptoms are not better accounted for by another mental disorder (e.g., a Depressive Disorder).
• The symptoms are not a manifestation of another medical condition (e.g., hyperthyroidism) and are not due to the effects of a substance or medication on the central nervous system (e.g., caffeine, cocaine), including withdrawal effects (e.g., alcohol, benzodiazepines).
• The symptoms result in significant distress about experiencing persistent anxiety symptoms or significant impairment in personal, family, social, educational, occupational, or other important areas of functioning. If functioning is maintained, it is only through significant additional effort.

Additional Clinical Features:

• Some individuals with Generalized Anxiety Disorder may only report general apprehensiveness accompanied by chronic somatic symptoms without being able to articulate specific worry content.
• Behavioural changes such as avoidance, frequent need for reassurance (especially in children), and procrastination may be seen. These behaviours typically represent an effort to reduce apprehension or prevent untoward events from occurring.

Boundary with Normality (Threshold):

• Anxiety and worry are normal emotional/cognitive states that commonly occur when people are under stress. At optimal levels, anxiety and worry may help to direct problem-solving efforts, focus attention adaptively, and increase alertness. Normal anxiety and worry are usually sufficiently self-regulated that they do not interfere with functioning or cause marked distress. In Generalized Anxiety Disorder, the anxiety or worry is excessive, persistent, and intense, and may have a significant negative impact on functioning. Individuals under extremely stressful circumstances (e.g., living in a war zone) may experience intense and impairing anxiety and worry that is appropriate to their environmental circumstances. These experiences should not be regarded as symptomatic of Generalized Anxiety Disorder if they occur only under such circumstances.

Course Features:

• Onset of Generalized Anxiety Disorder may occur at any age. However, the typical age of onset is during the early-to-mid 30s.
• Earlier onset of symptoms is associated with greater impairment of functioning and presence of co-occurring mental disorders.
• Severity of Generalized Anxiety Disorder symptoms often fluctuates between threshold and subthreshold forms of the disorder and full remission of symptoms is uncommon.
• Although the clinical features of Generalized Anxiety Disorder generally remain consistent across the lifespan, the content of the individual’s worry may vary over time and there are differences in worry content among different age groups. Children and adolescents tend to worry about the quality of academic and sports-related performance, whereas adults tend to worry more about their own well-being or that of their loved ones.

Developmental Presentations:

• Anxiety or Fear-Related Disorders are the most prevalent mental disorders of childhood and adolescence. Among these disorders, Generalized Anxiety Disorder is one of the most common in late childhood and adolescence.
• Occurrence of Generalized Anxiety Disorder increases across late childhood and adolescence with development of cognitive abilities that support the capacity for worry, which is a core feature of the disorder. As a result of their less developed cognitive abilities, Generalized Anxiety Disorder is uncommon in children younger than 5. Girls tend to have an earlier symptom onset than their same age male peers.
• While the essential features of Generalized Anxiety Disorder still apply to children and adolescents, specific manifestations of worry in children may include being overly concerned and compliant with rules as well as a strong desire to please others. Affected children may become upset when they perceive peers as acting out or being disobedient. Consequently, children and adolescents with Generalized Anxiety Disorder may be more likely to report excessively on their peers’ misbehaviour or to act as an authority figure around peers, condemning misbehaviour. This may have a negative effect on affected individuals’ interpersonal relationships.
• Children and adolescents with Generalized Anxiety Disorder may engage in excessive reassurance seeking from others, repeatedly asking questions, and may exhibit distress when faced with uncertainty. They may be overly perfectionistic, taking additional time to complete tasks, such as homework or classwork. Sensitivity to perceived criticism is common.
• When Generalized Anxiety Disorder does occur in children, somatic symptoms, particularly those related to sympathetic autonomic overactivity, may be prominent aspects of the clinical presentation. Common somatic symptoms in children with Generalized Anxiety Disorder include frequent headaches, abdominal pain, and gastrointestinal distress. Similar to adults, children and adolescents also experience sleep disturbances, including delayed sleep onset and night-time wakefulness.
• The number and content of worries typically manifests differently across childhood and adolescence. Younger children may endorse more concerns about their safety or their health or the health of others. Adolescents typically report a greater number of worries with content shifting to performance, perfectionism, and whether they will be able to meet the expectations of others.
• Adolescents with Generalized Anxiety Disorder may demonstrate excessive irritability and have an increased risk of co-occurring depressive symptoms.

Culture-Related Features:

• For many cultural groups, somatic complaints rather than excessive worry may predominate in the clinical presentation. These symptoms may involve a range of physical complaints not typically associated with Generalized Anxiety Disorder such as dizziness and heat in the head.
• Realistic worries may be misjudged as excessive without appropriate contextual information. For example, migrant workers may worry greatly about being deported, but this may be related to actual deportation threats by their employer. On the other hand, evidence of worries across several different aspects of everyday life may be difficult to establish when an individual places emphasis on a single overwhelming source of worry (e.g., financial concerns).
• Worry content may vary by cultural group, related to topics that are salient in the milieu. For example, in societies where relationships with deceased relatives are important, worry may focus on their spiritual status in the afterlife. Worry in more individualistic cultures may emphasize personal achievement, fulfilment of expectations, or self-confidence.

Sex- and/or Gender-Related Features:

• Lifetime prevalence of Generalized Anxiety Disorder is approximately twice as high among women.
• Although symptom presentation does not vary by gender including the common co-occurrence of Generalized Anxiety Disorder and Depressive Disorders, men are more likely to experience co-occurring Disorders due to Substance Use.

Boundaries with Other Disorders and Conditions (Differential Diagnosis):

• Boundary with Panic Disorder: Panic Disorder is characterized by recurrent, unexpected, self-limited episodes of intense fear or anxiety. Generalized Anxiety Disorder is differentiated by a more persistent and less circumscribed chronic feeling of apprehensiveness usually associated with worry about a variety of different everyday life events. Individuals with Generalized Anxiety Disorder may experience panic attacks that are triggered by specific worries. If an individual with Generalized Anxiety Disorder experiences panic attacks exclusively in the context of the worry about a variety of everyday life events or general apprehensiveness without the presence of unexpected panic attacks, an additional diagnosis of Panic Disorder is not warranted and the presence of panic attacks may be indicated using the ‘with panic attacks’ specifier. However, if unexpected panic attacks also occur, an additional diagnosis of Panic Disorder may be assigned.
• Boundary with Social Anxiety Disorder: In Social Anxiety Disorder, symptoms occur in response to feared social situations (e.g., speaking in public, initiating a conversation) and the primary focus of apprehension is being negatively evaluated by others. Individuals with Generalized Anxiety Disorder may worry about the implications of performing poorly or failing an examination but are not exclusively concerned about being negatively evaluated by others.
• Boundary with Separation Anxiety Disorder: Individuals with Generalized Anxiety Disorder may worry about the health and safety of attachment figures, as in Separation Anxiety Disorder, but their worry also extends to other aspects of everyday life.
• Boundary with Depressive Disorders: Generalized Anxiety Disorder and Depressive Disorders can share several features such as somatic symptoms of anxiety, difficulty with concentration, sleep disruption, and feelings of dread associated with pessimistic thoughts. Depressive Disorders are differentiated by the presence of low mood or loss of pleasure in previously enjoyable activities and other characteristic symptoms of Depressive Disorders (e.g., appetite changes, feelings of worthlessness, suicidal ideation). Generalized Anxiety Disorder may co-occur with Depressive Disorders, but should only be diagnosed if the diagnostic requirements for Generalized Anxiety Disorder were met prior to the onset of or following complete remission of a Depressive Episode.
• Boundary with Adjustment Disorder: Adjustment Disorder involves maladaptive reactions to an identifiable psychosocial stressor or multiple stressors characterized by preoccupation with the stressor or its consequences. Reactions may include excessive worry, recurrent and distressing thoughts about the stressor, or constant rumination about its implications. Adjustment Disorder centres on the identifiable stressor or its consequences, whereas in Generalized Anxiety Disorder, worry typically encompasses multiple areas of daily life and may include hypothetical concerns (e.g., that a negative life event may occur). Unlike individuals with Generalized Anxiety Disorder, those with Adjustment Disorder typically have normal functioning prior to the onset of the stressor(s). Symptoms of Adjustment Disorder generally resolve within 6 months.
• Boundary with Obsessive-Compulsive Disorder: In Obsessive-Compulsive Disorder, the focus of apprehension is on intrusive and unwanted thoughts, urges, or images (obsessions), whereas in Generalized Anxiety Disorder the focus is on everyday life events. In contrast to obsessions in Obsessive-Compulsive Disorder, which are usually experienced as unwanted and intrusive, individuals with Generalized Anxiety Disorder may experience their worry as a helpful strategy in averting negative outcomes.
• Boundary with Hypochondriasis (Health Anxiety Disorder) and Bodily Distress Disorder: In Hypochondriasis and Bodily Distress Disorder, individuals worry about real or perceived physical symptoms and their potential significance to their health status. Individuals with Generalized Anxiety Disorder experience somatic symptoms associated with anxiety and may worry about their health but their worry extends to other aspects of everyday life.
• Boundary with Post-Traumatic Stress Disorder: Individuals with Post-Traumatic Stress Disorder develop hypervigilance as a consequence of exposure to the traumatic stressor and may become apprehensive that they or others close to them may be under immediate threat either in specific situations or more generally. Individuals with Post-Traumatic Stress Disorder may also experience anxiety triggered by reminders of the traumatic event (e.g., fear and avoidance of a place where an individual was assaulted). In contrast, the anxiety and worry in individuals with Generalized Anxiety Disorder is directed toward the possibility of untoward events in a variety of life domains (e.g., health, finances, work).

REFERENCE:

International Classification of Diseases Eleventh Revision (ICD-11). Geneva: World Health Organization; 2022. License: CC BY-ND 3.0 IGO.

https://creativecommons.org/licenses/by-nc-nd/3.0/igo/