Agoraphobia Health Article

Definition

Agoraphobia is an anxiety disorder characterized by intense fear related to being in situations from which escape might be difficult or embarrassing (i.e., being on a bus or train), or in which help might not be available in the event of a panic attack or panic symptoms. Panic is defined as extreme and unreasonable fear and anxiety.

According to the handbook used by mental health professionals to diagnose mental disorders, the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision, also known as the DSM-IV-TR, patients with agoraphobia are typically afraid of such symptoms as feeling dizzy, having an attack of diarrhea, fainting, or "going crazy."

The word "agoraphobia" comes from two Greek words that mean "fear" and "marketplace." The anxiety associated with agoraphobia leads to avoidance of situations that involve being outside one's home alone, being in crowds, being on a bridge, or traveling by car or public transportation. Agoraphobia may intensify to the point that it interferes with a person's ability to take a job outside the home or to carry out such ordinary errands and activities as picking up groceries or going out to a movie.

Description

The close association in agoraphobia between fear of being outside one's home and fear of having panic symptoms is reflected in DSM-IV-TR classification of two separate disorders: panic disorder (PD) with agoraphobia, and agoraphobia without PD. PD is essentially characterized by sudden attacks of fear and panic. There may be no known reason for the occurrence of panic attacks; they are frequently triggered by fear-producing events or thoughts, such as driving, or being in an elevator. PD is believed due to an abnormal activation of the body's hormonal system, causing a sudden "fight-or-flight" response.

The chief distinction between PD with agoraphobia and agoraphobia without PD is that patients who are diagnosed with PD with agoraphobia meet all criteria for PD; in agoraphobia without PD, patients are afraid of panic-like symptoms in public places, rather than full-blown panic attacks.

People with agoraphobia appear to suffer from two distinct types of anxiety— panic, and the anticipatory anxiety related to fear of future panic attacks. Patients with agoraphobia are sometimes able to endure being in the situations they fear by "gritting their teeth," or by having a friend or relative accompany them.

In the United States' diagnostic system, the symptoms of agoraphobia can be similar to those of specific phobia and social phobia. In agoraphobia and specific phobia, the focus is fear itself; with social phobia, the person's focus is on how others are perceiving him/her. Patients diagnosed with agoraphobia tend to be more afraid of their own internal physical sensations and similar cues than of the reactions of others per se. In cases of specific phobia, the person fears very specific situations, whereas in agoraphobia, the person generally fears a variety of situations (being outside of the home alone, or traveling on public transportation including a bus, train, or automobile, for example). An example of a patient diagnosed with a specific phobia rather than agoraphobia would be the person whose fear is triggered only by being in a bus, rather than a car or taxi. The fear of the bus is more specific than the agoraphobic's fear of traveling on public transportation in general. The DSM-IVTR remarks that the differential diagnosis of agoraphobia "can be difficult because all of these conditions are characterized by avoidance of specific situations."

Causes

GENETIC.As of 2002, the causes of agoraphobia are complex and not completely understood. It has been known for some years that anxiety disorders tend to run in families. Recent research has confirmed earlier hypotheses that there is a genetic component to agoraphobia, and that it can be separated from susceptibility to PD. In 2001 a team of Yale geneticists reported the discovery of a genetic locus on human chomosome 3 that governs a person's risk of developing agoraphobia. PD was found to be associated with two loci: one on human chromosome 1 and the other on chromosome 11q. The researchers concluded that agoraphobia and PD are common; they are both inheritable anxiety disorders that share some, but not all, of their genetic loci for susceptibility.

INNATE TEMPERAMENT. A number of researchers have pointed to inborn temperament as a broad vulnerability factor in the development of anxiety and mood disorders. In other words, a person's natural disposition or temperament may become a factor in developing a number of mood or anxiety disorders. Some people seem more sensitive throughout their lives to events, but upbringing and life history are also important factors in determining who will develop these disorders. Children who manifest what is known as "behavioral inhibition" in early infancy are at increased risk for developing more than one anxiety disorder in adult life—particularly if the inhibition remains over time. (Behavioral inhibition refers to a group of behaviors that are displayed when the child is confronted with a new situation or unfamiliar people.) These behaviors include moving around, crying, and general irritability, followed by withdrawing, seeking comfort from a familiar person, and stopping what one is doing when one notices the new person or situation. Children of depressed or anxious parents are more likely to develop behavioral inhibition.

PHYSIOLOGICAL REACTIONS TO ILLNESS. Another factor in the development of PD and agoraphobia appears to be a history of respiratory disease. Some researchers have hypothesized that repeated episodes of respiratory disease would predispose a child to PD by making breathing difficult and lowering the threshold for feeling suffocated. It is also possible that respiratory diseases could generate fearful beliefs in the child's mind that would lead him or her to exaggerate the significance of respiratory symptoms.

LIFE EVENTS.About 42% of patients diagnosed with agoraphobia report histories of real or feared separation from their parents or other caretakers in childhood. This statistic has been interpreted to mean that agoraphobia in adults is the aftermath of unresolved childhood separation anxiety. The fact that many patients diagnosed with agoraphobia report that their first episode occurred after the death of a loved one, and the observation that other agoraphobics feel safe in going out as long as someone is with them, have been taken as supportive evidence of the separation anxiety hypothesis.

LEARNED BEHAVIOR. There are also theories about human learning that explain agoraphobia. It is thought that a person's initial experience of panic-like symptoms in a specific situation— for example, being alone in a subway station— may lead the person to associate physical symptoms of panic with all subway stations. Avoiding all subway stations would then reduce the level of the person's discomfort. Unfortunately, the avoidance strengthens the phobia because the person is unlikely to have the opportunity to test whether subway stations actually cause uncomfortable physical sensations. One treatment modality—exposure therapy—is based on the premise that phobias can be "unlearned" by reversing the pattern of avoidance.

SOCIAL FACTORS RELATED TO GENDER.Gender role socialization has been suggested as an explanation for the fact that the majority of patients with agoraphobia are women. One form of this hypothesis maintains that some parents still teach girls to be fearful and timid about venturing out in public. Another version relates agoraphobia to the mother-daughter relationship, maintaining that mothers tend to give daughters mixed messages about becoming separate individuals. As a result, girls grow up with a more fragile sense of self, and may stay within the physical boundaries of their home because they lack a firm sense of their internal psychological boundaries.