Anxiety disorders are among the most prevalent of psychological disorders, affecting up to 20% of the population. The key features shared by the anxiety disorders include excessive or unrealistic fear and anxiety, avoidance of feared objects and situations, and excessive attempts to reduce discomfort or to protect oneself from potential threat. In addition, for an anxiety disorder to be diagnosed, the person has to report considerable distress over having the anxiety symptoms, or the symptoms have to cause significant interference in the individual’s life. In fact, in severe cases, people with anxiety disorders may be unable to work, develop relationships, or even leave their homes. Anxiety disorders often pose an enormous financial burden on society. For example, they often lead to lower work productivity and considerable increases in health care utilization.
Types of Anxiety Disorders
The fourth edition of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) describes 11 different anxiety disorders. Each of these is listed in Table 1, along with their most important defining features. Although other psychological problems may be associated with extreme fear or anxiety (e.g., eating disorders are associated with a fear of gaining weight), only the conditions listed in Table 1 are officially classified as anxiety disorders in the DSM-IV.
Demographic Features of the Anxiety Disorders
Anxiety disorders can occur across a wide range of cultures, ages, sexes, and income levels. In most cases, anxiety disorders are more common in women than in men. The more frequent occurrence in women is most pronounced for Panic Disorder with Agoraphobia and certain specific phobias (particularly animals and storms). For other anxiety disorders, such as Social Anxiety Disorder, blood and needle phobias, and Obsessive-Compulsive Disorder (OCD), the differences between men and women are smaller. The typical onset of anxiety disorders varies, with some tending to begin in early childhood (e.g., animal phobias), others beginning, on average, during the teen years (e.g., Social Anxiety Disorder, OCD), and others tending to begin in early adulthood (e.g., Panic Disorder).
Causes of Anxiety Disorders
Although there are still many unanswered questions about how anxiety disorders begin, a number of contributing factors have been identified. From a biological perspective, there is mounting evidence supporting the role of genetics. In addition, certain neurotransmitters in the brain appear to play a role. For example, OCD appears to be associated with abnormal levels of serotonin, whereas Panic Disorder appears to be associated with abnormalities in the norepinephrine system, as well as others. Differences have also been shown in patterns of blood flow in the brains of individuals with and without anxiety disorders. Interestingly, these patterns may normalize following treatment, either with medication or with psychological treatment.
From a psychological perspective, life experiences appear to play a role in the onset and exacerbation of anxiety disorders. For example, life stress can contribute to the development of Panic Disorder and other anxiety disorders. In addition, traumatic events in particular situations may trigger the onset of Post-Traumatic Stress Disorder (PTSD), a specific phobia, or another anxiety-related problem.
In addition to the role of life events, there is significant evidence that anxious biases in a person’s beliefs, assumptions, and predictions can contribute to anxiety symptoms. For example, individuals with Social Anxiety Disorder tend to be overly concerned that others will judge them in a negative way. Likewise, individuals with Panic Disorder tend to misinterpret normal physical sensations, such as dizziness or breathlessness, as being dangerous.
Table 1. Key Features of the Anxiety Disorders
Panic Disorder With or Without Agoraphobia
- The presence of unexpected or uncued panic attacks (a panic attack is a rush of fear or discomfort that peaks quickly and is accompanied by four or more associated symptoms, such as racing heart, dizziness, breathlessness, and others).
- The presence of anxiety over the panic attacks, worry about the possible consequences of attacks (e.g., dying, losing control, “going crazy”), or a change in behavior related to the attacks.
- Agoraphobia often occurs with Panic Disorder. This refers to anxiety about, or avoidance of, situations in which escape might be difficult or help unavailable in the event of a panic attack or panic-like symptoms. Feared situations may include crowded places, travel, driving, enclosed places, and others.
Agoraphobia Without History of Panic Disorder
- The presence of Agoraphobia, without ever having met the full diagnostic criteria for Panic Disorder.
- An excessive or unrealistic fear of a specific object or situation, such as an animal, heights, blood, needles, elevators, or flying.
Social Anxiety Disorder (Social Phobia)
- An excessive or unrealistic fear of one or more social or performance situations, such as public speaking, conversations, or meeting new people, The fear is of being embarrassed, humiliated, or judged by others.
Obsessive-Compulsive Disorder (OCD)
- The presence of obsessions (i.e., thoughts, images, or impulses that are perceived as intrusive and distressing), such as fears of being contaminated, doubts about one’s actions, or irrational fears of hurting others).
- The presence of compulsions (i.e., repetitive behaviors, such as checking, washing, or counting, that are used to reduce anxiety or to prevent something bad from happening).
Post-Traumatic Stress Disorder (PTSD)
- The experience of a trauma in which an individual has been confronted with a threat to his or her physical well-being or to the physical well-being of another individual (e.g., experiencing a rape, assault, or accident; witnessing an act of violence).
- 1 month or more in which the individual experiences recurrent recollections of the trauma, avoidance of situations that remind him or her of the trauma, emotional numbing, symptoms of arousal, and hypervigilance.
Acute Stress Disorder
- Similar to PTSD, except with a duration of between 2 days and 4 weeks.
Generalized Anxiety Disorder (GAD)
- Frequent worry about a number of different areas (e.g., work, family, health) with difficulty controlling the worry and a number of associated symptoms (e.g., muscle tension, sleep problems, poor concentration).
Anxiety Disorder Due to a General Medical Condition
- Significant problems with anxiety that are directly caused by a medical condition (e.g., panic attack symptoms triggered by hyperthyroidism).
Substance-Induced Anxiety Disorder
- Significant problems with anxiety that are directly caused by a substance (e.g., panic attack symptoms triggered by cocaine use, caffeine, or alcohol withdrawal).
Anxiety Disorder Not Otherwise Specified
- Significant problems with anxiety that do not meet the official criteria for another anxiety disorder or for some other psychological disorder.
Treatment of Anxiety Disorders
Anxiety disorders are among the most treatable of psychological problems. Most individuals who receive appropriate treatment experience a significant reduction in symptoms. For Substance-Induced Anxiety Disorders and Anxiety Disorders Due to a General Medical Condition, the focus is generally on reducing the substance use or on treating the medical condition that is causing the problem. However, for the other anxiety disorders, evidence-based treatments include medications, cognitive-behavioral therapy (CBT), or a combination of these approaches.
The selective serotonin reuptake inhibitors (SSRIs), such as paroxetine, fluoxetine, and sertraline, have been shown to be useful for treating most of the anxiety disorders. Other antidepressants (e.g., venlavaxine, imipramine) are also useful for particular anxiety disorders. Anxiolytic medications (especially the benzodiazepines, such as alprazolam and diazepam) are also effective for reducing anxiety, although they are usually prescribed with caution due to the potential for abuse and the difficulty that some people have discontinuing these drugs. All of the anxiety disorders, except perhaps specific phobias, have been shown to improve following treatment with medications.
CBT includes a number of components. First, patients are encouraged to expose themselves to the situations they fear until their fear subsides. For example, individuals with Social Anxiety Disorder may practice meeting new people, engaging in conversations, or purposely making minor mistakes in social situations. Individuals with Panic Disorder are encouraged to expose themselves to the physical feelings they fear (e.g., running in place until their fear of a racing heart decreases), in addition to the feared agoraphobic situations. In the case of OCD, the exposure is combined with prevention of the compulsive rituals (e.g., touching “contaminated” objects without washing one’s hands).
Second, cognitive therapy is often used to help individuals to replace their anxious thoughts with more balanced, realistic perspectives. For example, an individual with Generalized Anxiety Disorder (GAD) who worries whenever his or her spouse is late would be encouraged to consider all of the possible factors that may contribute to the lateness, rather than assuming the worst.
Third, treatment may include teaching the individual other relevant skills. For example, people with GAD often benefit from relaxation or meditation-based treatments. Individuals with Social Anxiety Disorder may benefit from learning to communicate more effectively.
Finally, treatment often includes a combination of medication and CBT. Generally, CBT, medications, and combined treatments are equally effective on average, although some individuals respond better to one approach than another. In the long term, after treatment has been discontinued, symptoms are more likely to return following treatment with medications than they are following treatment with CBT.