Agoraphobia

Agoraphobia is an anxiety disorder where an individual has intense fears about at least two different types of situations, with the fear being that escape may be difficult or help may be unavailable if panic-like symptoms occur.

• The annual prevalence of agoraphobia is about 1.7%.^[1]
• The incidence peaks in late adolescence and early adulthood.
• Females are twice as likely as males to experience agoraphobia.

• The course of agoraphobia is usually persistent and chronic.
• If untreated, the remission rate is around 10%.
• More than 33% of individuals with agoraphobia are homebound and unable have gainful employment.^[2]

• Other anxiety disorders such as specific phobias, panic disorder, and social anxiety disorder are common.
  • These may precede the onset of agoraphobia.^[3]
• Major depressive disorder, PTSD, and alcohol use disorder are also common as well, typically as a secondary result of agoraphobia.

• Anxiety disorders, depressive disorders, substance use disorders, and personality disorders, can be comorbid with agoraphobia.
• Temperamental factors such as anxiety sensitivity (belief that anxiety symptoms are harmful)
• Environmental factors such as reduced warmth and increased overprotection by parental figures, and adverse childhood events are risk factors.
• The heritability for agoraphobia is is 61%.^[4], and has the most genetic association of the phobias.

• What counts as avoidance is difficult to judge aross cultures and sociocultural contexts (e.g. - it may be socioculturally appropriate for orthodox Muslim women to avoid leaving the house alone, and this is not indicative of agoraphobia).^[5]

The DSM-5 created agoraphobia as a separate diagnosis, whereas in the previous version, DSM-IV, panic disorder could be diagnosed as “panic disorder with agoraphobia” or “panic disorder without agoraphobia.” Thus, much of the research on agoraphobia is based on the DSM-IV definition.^[6]

Marked fear or anxiety about at least 2 of the following 5 situations:

1. Public transportation (e.g. - automobiles, buses, trains, ships, planes)
2. Open spaces (e.g. - parking lots, malls, marketplaces, bridges)
3. Enclosed places (e.g. - rooms, shops, theatres, cinemas)
4. Crowds or standing in line
5. Being outside of home alone

The individual fears or avoids these situations because of thoughts that:

1. Escape might be difficult, or
2. Help might not be available in the event of developing panic-like symptoms or other incapacitating or embarrassing symptoms (e.g. - fear of falling or fear of incontinence in the elderly).

The agoraphobic situations almost always provoke fear or anxiety.

The agoraphobic situations are actively avoided, require the presence of a companion, or are endured with intense fear or anxiety.

The fear or anxiety is out of proportion to the actual danger posed by the agoraphobic situations and to the sociocultural context.

The fear, anxiety, or avoidance is persistent, typically lasting for 6 months or more.

The fear, anxiety, or avoidance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning.

If another medical condition (e.g. - inflammatory bowel disease, Parkinson’s disease) is present, the fear, anxiety, or avoidance is clearly excessive.

The fear, anxiety, or avoidance is not better explained by the symptoms of another mental disorder:

• The symptoms are not confined to a specific phobia, situational type
• Do not involve only social situations (social anxiety disorder)
• Do not relate exclusively to obsessions (obsessive-compulsive disorder)
• Do not relate to defects or flaws in physical appearance (body dysmorphic disorder)
• Do not relate to reminders of traumatic events (post-traumatic stress disorder)
• Do not relate to fear of separation (separation anxiety disorder).

• Individuals with agoraphobia frequently believe that escape from such their feared situations might be difficult (e.g. - “I won't be able to get out of here”) or that help might be unavailable (e.g. - “There will be nobody there to help me”) when the panic-like symptoms or other incapacitating or embarrassing symptoms occur.
• Beyond the panic attack symptoms (see above), other incapacitating or embarrassing symptoms include symptoms such as:
  • Vomiting and inflammatory bowel symptoms
  • In older adults, a fear of falling
  • In children, a sense of disorientation and getting lost
• It is important to recognize that the fear or anxiety is evoked nearly every time the individual comes into contact with the feared situation.
• The avoidance can become so impairing that the person is completely homebound and refuses to leave.

• Panic and Agoraphobia Scale (PAS)^[7]

When diagnostic criteria for agoraphobia and another disorder are fully met, both diagnoses should be assigned, unless the fear, anxiety, or avoidance of agoraphobia is attributable to the other disorder. Weighting of criteria and clinical judgment may be helpful in some cases.

• Specific phobia, situational type
  • Differentiating agoraphobia from situational specific phobia can be challenging in some cases, because these conditions share similar symptoms.
  • Specific phobia, situational type, should be diagnosed instead of agoraphobia if the fear, anxiety, or avoidance is limited to just 1 of the agoraphobic situations.
  • If there are fears from 2 or more agoraphobic situations, a diagnosis of agoraphobia is warranted. Thus, if the situation is feared for reasons other than panic-like symptoms or other incapacitating or embarrassing symptoms (e.g. - fears of being directly harmed by the situation itself, such as fear of being bitten by a dog), then the diagnosis of specific phobia is more appropriate.
• Separation anxiety disorder
  • In separation anxiety disorder, the thoughts are about be away from significant others and the home environment (i.e. - parents or other attachment figures). Contrast this with agoraphobia, where the focus is on panic-like symptoms or other incapacitating or embarrassing symptoms in the two or more feared situations.
• Social anxiety disorder (social phobia)
  • In social anxiety disorder, the focus is on fear of being negatively evaluated.
• Panic disorder
  • Agoraphobia should not be diagnosed if the avoidance behaviors associated with the panic attacks do not extend to avoidance of 2 or more agoraphobic situations.
• Acute stress disorder and posttraumatic stress disorder (PTSD)
  • Acute stress disorder and PTSD can be differentiated from agoraphobia by asking whether the fear, anxiety, or avoidance is related only to situations that remind the individual of a traumatic event.
  • If the fear, anxiety, or avoidance is restricted to reminders of trauma, and if the avoidance behavior does not extend to two or more agoraphobic situations, then agoraphobia should not be diagnosed.
• Major depressive disorder
  • In major depressive disorder, the individual may avoid leaving the home because of apathy, loss of energy, low self-esteem, and anhedonia. If the avoidance is unrelated to fears of panic-like or other incapacitating or embarrassing symptoms, then agoraphobia should not be diagnosed.
• Other medical conditions
  • Agoraphobia is not diagnosed if the avoidance of situations is due to a physiological consequence of a medical condition, based on history, laboratory findings, and a physical examination. This includes medical conditions such as neurodegenerative disorders with motor symptoms (e.g. - Parkinson's disease, multiple sclerosis) and cardiovascular disorders.
  • Individuals with some medical conditions may avoid situations due to realistic concerns about being incapacitated (e.g. - fainting in transient ischemic attacks) or being embarrassed (e.g. - diarrhea in Crohn's disease). Thus, the diagnosis of agoraphobia should be given only when the fear or avoidance is clearly in excess of that usually associated with these medical conditions.

• Depending on the initial presenting symptoms (e.g. - dizziness, tachycardia), potential investigations can include: CBC, fasting glucose, fasting lipid profiles, electrolytes, liver enzymes, serum bilirubin, serum creatinine, urinalysis, urine toxicology for substance use, thyroid stimulating hormone (TSH).^[8]
• An ECG and beta-HCG should be ordered if relevant.

• As clinically indicated.

• The treatment for agoraphobia is similar to treatment for panic disorder, as most studies have been done under the DSM-IV criteria (and agoraphobia was a subtype in panic disorder).