Overview

Definition

Agoraphobia is fear or anxiety in a situation in which it would be difficult to escape or to readily obtain help in the event that one develops panic-like symptoms, thus leading to avoidance.

• The condition involves a fear of actual or potential exposure to public spaces and active attempts to avoid this situation.
• Patients with phobic disorders might have good insight and know that their fear is excessive, or they might have poor insight.

Epidemiology

• Prevalence of agoraphobia: around 1.7%
• Median age at presentation: 20 years
• More common in females than in males
• Most commonly occurs in conjunction with panic disorder Panic disorder Panic disorder is a condition marked by recurrent and episodic panic attacks that occur abruptly and without a trigger. These episodes are time-limited and present with cardiorespiratory (palpitations, shortness of breath, choking), GI (nausea, abdominal distress), and neurologic (paresthesias, lightheadedness) symptoms. Panic Disorder, but may occur independently
• Presence of panic disorder Panic disorder Panic disorder is a condition marked by recurrent and episodic panic attacks that occur abruptly and without a trigger. These episodes are time-limited and present with cardiorespiratory (palpitations, shortness of breath, choking), GI (nausea, abdominal distress), and neurologic (paresthesias, lightheadedness) symptoms. Panic Disorder or other phobias increase the risk of having agoraphobia.

Pathophysiology

• Genetic factors: family history increases the risk of developing any anxiety disorder, but not agoraphobia specifically.
• Neurobiologic factors:
  • Studies showed increased activation in the ventral striatum and left insula.
  • More anxiety in anticipating the feared situation than from experiencing actual situation
• Personality traits:
  • Introversion: associated with increased risk of agoraphobia and situational avoidance
  • Anxiety sensitivity: 
    • Fear of the sensations or behaviors of anxiety due to the belief that the anxiety symptoms are harmful
    • ↑ Panic disorder and agoraphobia without panic attacks
  • Dependent personality: a marker of risk for agoraphobia
• Social or environmental factors:
  • Childhood fears
  • Traumatic events (especially if the previous experience indicates that escaping or removing one’s self from the situation reduces the anxiety)

Clinical Presentation and Diagnosis

Clinical features

• Anxiety and/or avoidance of ≥ 2 situations that commonly include being in:
  • Crowds 
  • Being outside on their own
  • Wide open spaces (parking lots, bridges)
  • Enclosed places (shopping malls, groceries, movie theaters)
  • Public transportation
• Patients have a fear that they would not be able to escape or that help is not available when they have panic-like symptoms.
• The fear of the situation is intense and disproportionate to the real situation.
• Avoidance is done actively or the patient requires a companion.
• The symptoms significantly impair daily function.
• The anxiety is persistent, occurring for ≥ 6 months.
• These symptoms are not due to substance abuse or a medical or another mental disorder.

Diagnosis

• Clinical, based on symptoms reported
• Some tools used:
  • Agoraphobia subscale of the Fear Questionnaire
  • Anxiety and Related Disorders Interview Schedule for DSM-5 (ADIS-5)  
    • Comprehensive and time-consuming
    • Not ideal for general practice settings

Management

• Agoraphobia is associated with panic disorder Panic disorder Panic disorder is a condition marked by recurrent and episodic panic attacks that occur abruptly and without a trigger. These episodes are time-limited and present with cardiorespiratory (palpitations, shortness of breath, choking), GI (nausea, abdominal distress), and neurologic (paresthesias, lightheadedness) symptoms. Panic Disorder, and treatment studies have often involved patients with both agoraphobia and panic disorders.
• Both pharmacotherapy and psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy showed similar efficacy. 
  • Choice is based on availability and patient preference.
  • If monotherapy shows no improvement, the next step is to add the other therapy. 
• Psychotherapy: 
  • CBT, which includes gradual exposure
  • Psychoeducation with breath training and muscle relaxation is also effective. 
  • Behavioral therapy aims to create systematic desensitization and to change maladaptive behaviors. 
• Medications:  
  • Benzodiazepines Benzodiazepines Benzodiazepines work on the gamma-aminobutyric acid type A (GABAA) receptor to produce inhibitory effects on the CNS. Benzodiazepines do not mimic GABA, the main inhibitory neurotransmitter in humans, but instead potentiate GABA activity. Benzodiazepines: 
    • Most rapid onset of action against panic symptoms
    • Higher potential for misuse 
    • Examples: alprazolam, lorazepam, clonazepam 
  • Antidepressants (selective serotonin reuptake inhibitors Serotonin Reuptake Inhibitors Antidepressants encompass several drug classes and are used to treat individuals with depression, anxiety, and psychiatric conditions, as well as those with chronic pain and symptoms of menopause. Antidepressants include selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and many other drugs in a class of their own. Serotonin Reuptake Inhibitors and Similar Antidepressant Medications (SSRIs)):
    • Have higher safety profile but take longer to achieve therapeutic dose
    • Examples: sertraline, citalopram, paroxetine

Other Anxiety Disorders

The following table summarizes the most important information about anxiety disorders.

Differential Diagnosis

• Panic disorder: chronic mental disorder marked by recurrent and episodic panic attacks that occur abruptly without a trigger. Panic disorder is associated with anxiety or fear of having another attack or its complications and some behavioral changes. If the panic attack is triggered by a known, identified trigger, then the correct diagnosis would be specific phobia. 
• Social phobia: also called social anxiety disorder Social anxiety disorder Social anxiety disorder, or social phobia, is a psychiatric illness marked by fear and avoidance of social interactions due to concerns about embarrassment. The disorder usually occurs in more than one social situation for more than 6 months and leads to a significant decline in function. Social Anxiety Disorder (SAD). Social phobia is the fear or avoidance of social interactions because of concerns about being embarrassed, occurring in > 1 social situation for > 6 months. Treatment includes CBT, antidepressants (SSRIs, serotonin–norepinephrine reuptake inhibitor (SNRIs)), and β-blockers for performance-only subtypes. People with social phobia are afraid of being negatively judged by others.  
• Separation anxiety disorder: pathologic exaggeration of anxiety that is a universal human developmental milestone in early childhood. This anxiety disorder is marked by real or anticipated separation from someone to whom the patient has made an attachment. Separation anxiety disorder is seen during the clinical exam, as the patient will be anxious about being detached from their loved ones, whereas in agoraphobia, the patient is focused on panic symptoms triggered from being in public.