For all talk related to Agoraphobia.
Agoraphobia is an anxiety disorder precipitated by the fear of having a symptom attack or panic attack in a setting from which there is no easy means of escape. As a result, sufferers of agoraphobia may avoid public and/or unfamiliar places. In severe cases, the sufferer may become confined to their home, experiencing difficulty traveling from this "safe place."
The word "agoraphobia" is an English adaptation of the Greek words agora (αγορά) and phobos (φόβος), and literally translates to "a fear of the forum." (A gathering place.)
Agoraphobia is a condition where the sufferer becomes anxious in environments that are unfamiliar or where he or she perceives that they have little control. Triggers for this anxiety may include crowds, wide open spaces or traveling, even short distances. This anxiety is often compounded by a fear of social embarrassment, as the agoraphobic fears the onset of a panic attack and appearing distraught in public.
Agoraphobics may experience panic attacks in situations where they feel trapped, insecure, out of control or too far from their personal comfort zone. In severe cases, an agoraphobic may be confined to his or her home.  Many people with agoraphobia are comfortable seeing visitors in a defined space that they feel in control of. Such people may live for years without leaving their homes, while happily seeing visitors in and working from their personal safety zones. If the agoraphobic leaves his or her safety zone, they may experience a panic attack.
The one-year prevalence of agoraphobia in the United States is about 5 percent.  According to the National Institute of Mental Health, approximately 3.2 million Americans ages 18-54 have agoraphobia at any given time. About one third of people with Panic Disorder progress to develop Agoraphobia. 
Agoraphobia occurs about twice as commonly among women as it does in men (Magee et al., 1996). The gender difference may be attributable to social-cultural factors that encourage, or permit, the greater expression of avoidant coping strategies by women. Other theories include the ideas that women are more likely to seek help and therefore be diagnosed, that men are more likely to abuse alcohol as a reaction to anxiety and be diagnosed as an alcoholic, and that traditional female sex roles prescribe women to react to anxiety by engaging in dependent and helpless behaviors.  Research results have not yet produced a single clear explanation as to the gender difference in agoraphobia.
Causes and Contributing Factors
There is no one single cause associated with agoraphobia. Instead, there are a number of factors that contribute to the development of agoraphobia. These factors include:
Having an anxious parent role model.
Being abused as a child.
Having an overly critical parent.
High need for approval.
High need control.
Oversensitivity to emotional stimuli.
Oversensitivity to hormone changes.
Oversensitivity to physical stimuli.
High amounts of sodium lactate in the bloodstream.
Additionally, research has uncovered a linkage between agoraphobia and difficulties with spatial orientation. Normal individuals are able to maintain balance by combining information from their vestibular system, their visual system and their proprioceptive sense. A disproportionate number of agoraphobics have weak vestibular function and consequently rely more on visual or tactile signals. They may become disoriented when visual cues are sparse as in wide open spaces or overwhelming as in crowds. Likewise, they may be confused by sloping or irregular surfaces. Compared to controls, in virtual reality studies, agoraphobics on average show impaired processing of changing audiovisual data. 
Most people who present to mental health specialists develop agoraphobia after the onset of panic disorder (American Psychiatric Association, 1998). Agoraphobia is best understood as an adverse behavioral outcome of repeated panic attacks and subsequent anxiety and preoccupation with these attacks that leads to an avoidance of situations where a panic attack could occur. In rare cases where agoraphobics do not meet the criteria used to diagnose Panic Disorder, the formal diagnosis of Agoraphobia Without History of Panic Disorder is used.
DSM-IV-TR Diagnostic Criteria
A) anxiety about being in places or situations from which escape might be difficult (or embarrassing) or in which help may not be available in the event of having an unexpected or situationally predisposed Panic Attack or panic-like symptoms. Agoraphobic fears typically involve characteristic clusters of situations that include being outside the home alone; being in a crowd, or standing in a line; being on a bridge; and traveling in a bus, train, or automobile.
B) The situations are avoided (e.g., travel is restricted) or else are endured with marked distress or with anxiety about having a Panic Attack or panic-like symptoms, or require the presence of a companion.
C) The anxiety or phobic avoidance is not better accounted for by another mental disorder, such as Social Phobia (e.g., avoidance limited to social situations because of fear of embarrassment), Specific Phobia (e.g., avoidance limited to a single situation like elevators), Obsessive-Compulsive Disorder (e.g., avoidance of dirt in someone with an obsession about contamination), Posttraumatic Stress Disorder (e.g., avoidance of stimuli associated with a severe stressor), or Separation Anxiety Disorder (e.g., avoidance of leaving home or relatives).
Association with Panic Attacks
Agoraphobia patients can experience sudden panic attacks when traveling to places where they fear they are out of control, help would be difficult to obtain, or they could be embarrassed. During a panic attack, epinephrine is released in large amounts, triggering the body's natural fight-or-flight response. A panic attack typically has an abrupt onset, building to maximum intensity within 10 to 15 minutes, and rarely lasts longer than 30 minutes.  Symptoms of a panic attack include palpitations, a rapid heartbeat, sweating, trembling, dizziness, tightness in the throat and shortness of breath. Many patients report a fear of dying or of losing control of emotions and/or behavior. 
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