Diagnostic Features
The essential feature of Generalized Anxiety Disorder is excessive anxiety and worry (apprehensive expectation), occurring more days than not for a period of at least 6 months, about a number of events or activities (Criterion A). The individual finds it difficult to control the worry (Criterion B). The anxiety and worry are accompanied by at least three additional symptoms from a list that includes restlessness, being easily fatigued, difficulty concentrating, irritability, muscle tension, and disturbed sleep (only one additional symptom is required in children) (Criterion C). The focus of the anxiety and worry is not confined to features of another Axis I disorder such as having a Panic Attack (as in Panic Disorder), being embarrassed in public (as in Social Phobia), being contaminated (as in Obsessive-Compulsive Disorder), being away from home or close relatives (as in Separation Anxiety Disorder), gaining weight (as in Anorexia Nervosa), having multiple physical complaints (as in Somatization Disorder), or having a serious illness (as in Hypochondriasis), and the anxiety and worry do not occur exclusively during Posttraumatic Stress Disorder (Criterion D). Although individuals with Generalized Anxiety Disorder may not always identify the worries as “excessive,” they report subjective distress due to constant worry, have difficulty controlling the worry, or experience related impairment in social, occupational, or other important areas of functioning (Criterion E). The disturbance is not due to the direct physiological effects of a substance (i.e., a drug of abuse, a medication, or toxin exposure) or a general medical condition and does not occur exclusively during a Mood Disorder, a Psychotic Disorder, or a Pervasive Developmental Disorder (Criterion F).

The intensity, duration, or frequency of the anxiety and worry is far out of proportion to the actual likelihood or impact of the feared event. The person finds it difficult to keep worrisome thoughts from interfering with attention to tasks at hand and has difficulty stopping the worry. Adults with Generalized Anxiety Disorder often worry about everyday, routine life circumstances such as possible job responsibilities, finances, the health of family members, misfortune to their children, or minor matters (such as household chores, car repairs, or being late for appointments). Children with Generalized Anxiety Disorder tend to worry excessively about their competence or the quality of their performance. During the course of the disorder, the focus of worry may shift from one concern to another.

Associated Features and Disorders
Associated with muscle tension, there may be trembling, twitching, feeling shaky, and muscle aches or soreness. Many individuals with Generalized Anxiety Disorder also experience somatic symptoms (e.g., sweating, nausea, or diarrhea) and an exaggerated startle response. Symptoms of autonomic hyperarousal (e.g., accelerated heart rate, shortness of breath, dizziness) are less prominent in Generalized Anxiety Disorder than in other Anxiety Disorders, such as Panic Disorder and Posttraumatic Stress Disorder. Depressive symptoms are also common.

Generalized Anxiety Disorder very frequently co-occurs with Mood Disorders (e.g., Major Depressive Disorder or Dysthymic Disorder), with other Anxiety Disorders (e.g., Panic Disorder, Social Phobia, Specific Phobia), and with Substance-Related Disorders (e.g., Alcohol or Sedative, Hypnotic, or Anxiolytic Dependence or Abuse). Other conditions that may be associated with stress (e.g., irritable bowel syndrome, headaches) frequently accompany Generalized Anxiety Disorder.

Specific Culture, Age, and Gender Features
There is considerable cultural variation in the expression of anxiety (e.g., in some cultures, anxiety is expressed predominantly through somatic symptoms, in others through cognitive symptoms). It is important to consider the cultural context when evaluating whether worries about certain situations are excessive.

In children and adolescents with Generalized Anxiety Disorder, the anxieties and worries often concern the quality of their performance or competence at school or in sporting events, even when their performance is not being evaluated by others. There may be excessive concerns about punctuality. They may also worry about catastrophic events such as earthquakes or nuclear war. Children with the disorder may be overly conforming, perfectionist, and unsure of themselves and tend to redo tasks because of excessive dissatisfaction with less-than-perfect performance. They are typically overzealous in seeking approval and require excessive reassurance about their performance and their other worries.

Generalized Anxiety Disorder may be overdiagnosed in children. In considering this diagnosis in children, a thorough evaluation for the presence of other childhood Anxiety Disorders should be done to determine whether the worries may be better explained by one of these disorders. Separation Anxiety Disorder, Social Phobia, and Obsessive-Compulsive Disorder are often accompanied by worries that may mimic those described in Generalized Anxiety Disorder. For example, a child with Social Phobia may be concerned about school performance because of fear of humiliation. Worries about illness may also be better explained by Separation Anxiety Disorder or Obsessive-Compulsive Disorder.

In clinical settings, the disorder is diagnosed somewhat more frequently in women than in men (about 55%-60% of those presenting with the disorder are female). In epidemiological studies, the sex ratio is approximately two-thirds female.

Prevalence
In a community sample, the 1-year prevalence rate for Generalized Anxiety Disorder was approximately 3%, and the lifetime prevalence rate was 5%. In anxiety disorder clinics, up to a quarter of the individuals have Generalized Anxiety Disorder as a presenting or comorbid diagnosis.

Course
Many individuals with Generalized Anxiety Disorder report that they have felt anxious and nervous all their lives. Although over half of those presenting for treatment report onset in childhood or adolescence, onset occurring after age 20 years is not uncommon. The course is chronic but fluctuating and often worsens during times of stress.

Familial Pattern
Anxiety as a trait has a familial association. Although early studies produced inconsistent findings regarding familial patterns for Generalized Anxiety Disorder, more recent twin studies suggest a genetic contribution to the development of this disorder. Furthermore, genetic factors influencing risk of Generalized Anxiety Disorder may be closely related to those for Major Depressive Disorder.

Differential Diagnosis
Generalized Anxiety Disorder must be distinguished from an Anxiety Disorder Due to a General Medical Condition. The diagnosis is Anxiety Disorder Due to a General Medical Condition if the anxiety symptoms are judged to be a direct physiological consequence of a specific general medical condition (e.g., pheochromocytoma, hyperthyroidism). This determination is based on history, laboratory findings, or physical examination. A Substance-Induced Anxiety Disorder is distinguished from Generalized Anxiety Disorder by the fact that a substance (i.e., a drug of abuse, a medication, or exposure to a toxin) is judged to be etiologically related to the anxiety disturbance. For example, severe anxiety that occurs only in the context of heavy coffee consumption would be diagnosed as Caffeine-Induced Anxiety Disorder, With Generalized Anxiety.

When another Axis I disorder is present, an additional diagnosis of Generalized Anxiety Disorder should be made only when the focus of the anxiety and worry is unrelated to the other disorder, that is, the excessive worry is not restricted to having a Panic Attack (as in Panic Disorder), being embarrassed in public (as in Social Phobia), being contaminated (as in Obsessive-Compulsive Disorder), gaining weight (as in Anorexia Nervosa), having a serious illness (as in Hypochondriasis), having multiple physical complaints (as in Somatization Disorder), or to concerns about the welfare of close relations or being away from them or from home (as in Separation Anxiety Disorder). For example, the anxiety present in Social Phobia is focused on upcoming social situations in which the individual must perform or be evaluated by others, whereas individuals with Generalized Anxiety Disorder experience anxiety whether or not they are being evaluated.

Several features distinguish the excessive worry of Generalized Anxiety Disorder from the obsessional thoughts of Obsessive-Compulsive Disorder. Obsessional thoughts are not simply excessive worries about everyday or real-life problems, but rather are ego-dystonic intrusions that often take the form of urges, impulses, and images in addition to thoughts. Finally, most obsessions are accompanied by compulsions that reduce the anxiety associated with the obsessions.

Anxiety is invariably present in Posttraumatic Stress Disorder. Generalized Anxiety Disorder is not diagnosed if the anxiety occurs exclusively during the course of Posttraumatic Stress Disorder. Anxiety may also be present in Adjustment Disorder, but this residual category should be used only when the criteria are not met for any other Anxiety Disorder (including Generalized Anxiety Disorder). Moreover, in Adjustment Disorder the anxiety occurs in response to a life stressor and does not persist for more than 6 months after the termination of the stressor or its consequences. Generalized anxiety is a common associated feature of Mood Disorders and Psychotic Disorders and should not be diagnosed separately if it occurs exclusively during the course of these conditions.

Several features distinguish Generalized Anxiety Disorder from nonpathological anxiety. First, the worries associated with Generalized Anxiety Disorder are difficult to control and typically interfere significantly with functioning, whereas the worries of everyday life are perceived as more controllable and can be put off until later. Second, the worries associated with Generalized Anxiety Disorder are more pervasive, pronounced, distressing, and of longer duration and frequently occur without precipitants. The more life circumstances about which a person worries excessively (finances, children’s safety, job performance, car repairs), the more likely the diagnosis. Third, everyday worries are much less likely to be accompanied by physical symptoms (e.g., excessive fatigue, restlessness, feeling keyed up or on edge, irritability), although this is less true of children.

Diagnostic criteria for Generalized Anxiety Disorder

A. Excessive anxiety and worry (apprehensive expectation), occurring more days than not for at least 6 months, about a number of events or activities (such as work or school performance).
B. The person finds it difficult to control the worry.
C. The anxiety and worry are associated with three (or more) of the following six symptoms (with at least some symptoms present for more days than not for the past 6 months). Note: Only one item is required in children.
(1) restlessness or feeling keyed up or on edge
(2) being easily fatigued
(3) difficulty concentrating or mind going blank
(4) irritability
(5) muscle tension
(6) sleep disturbance (difficulty falling or staying asleep, or restless unsatisfying sleep)

D. The focus of the anxiety and worry is not confined to features of an Axis I disorder, e.g., the anxiety or worry is not about having a Panic Attack (as in Panic Disorder), being embarrassed in public (as in Social Phobia), being contaminated (as in Obsessive-Compulsive Disorder), being away from home or close relatives (as in Separation Anxiety Disorder), gaining weight (as in Anorexia Nervosa), having multiple physical complaints (as in Somatization Disorder), or having a serious illness (as in Hypochondriasis), and the anxiety and worry do not occur exclusively during Posttraumatic Stress Disorder.
E. The anxiety, worry, or physical symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
F. The disturbance is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition (e.g., hyperthyroidism) and does not occur exclusively during a Mood Disorder, a Psychotic Disorder, or a Pervasive Developmental Disorder.