Agoraphobia: An Evolving Understanding of Definitions and Treatment

Agoraphobia can be defined as “irrational or disproportionate fear of a range of situations in which a person believes escape or access to help may be impossible, very difficult, or very embarrassing if he or she develops panic-like symptoms or some other incapacitating loss of control.”¹

The lifetime prevalence of agoraphobia in the general US population is about 2%,² with 1 study showing a higher prevalence (10.4%) in adults older than 65 years.³ Despite its high prevalence in older adults, the average age of onset is actually between ages 25 and 30 years.⁴ Agoraphobia is twice as common in women and is also more disabling in women compared with men.⁵

During their lifetimes, 87.3% of individuals with agoraphobia will also meet criteria for another psychiatric disorder, including panic disorder, social anxiety disorder, specific phobia, generalized anxiety disorder (GAD),⁴ and substance use disorder.⁶

An Evolving Story

Although agoraphobia is very common, it is often misunderstood, according to C. Alec Pollard, PhD, professor emeritus of family and community medicine at Saint Louis University School of Medicine and director of the Center for OCD and Anxiety-Related Disorders at the Saint Louis Behavioral Medicine Institute. For example, a common misconception is that agoraphobia necessarily means fear of going outside or that individuals with agoraphobia are usually homebound.

“The understanding of agoraphobia has been evolving,” Dr Pollard told Psychiatry Advisor, noting that the term was originally coined in 1871 by the German neurologist Westphal, who used the Greek word “agora,” meaning market, to refer to the fear of large, open spaces.⁷

“The focus was on the external environment, on being away from home or being in public,” Dr Pollard explained, adding that Freud also described agoraphobia, and “foreshadowed the eventual treatment of choice, which is exposure, because insight alone would not be sufficient.”

He described 2 parallel trajectories of research and understanding. “Behavioral therapists were working with exposure therapy and having people gradually face their phobias.”

In this context, “the focus remained on the external situation; for example, going to the mall, being around crowds, and developing a hierarchy of tasks to be exposed, one step at a time, to the object of the fear.”

A second line of approach developed more by the psychiatric community focused on panic attacks, “which were often the center of the fear,” said Dr Pollard, who is the coauthor of The Agoraphobia Workbook: A Comprehensive Program to End Your Fear of Symptom Attacks.⁸

“The fear is not of the situation per se, such as being in a crowd, but of having a panic attack in that particular situation,” he said.

Agoraphobia has been reframed as “fear of fear,”⁹ bringing the 2 lines of thinking into accord. However, Dr Pollard noted that medical research “focused more on stopping the panic attacks and understanding their biological underpinnings,” leading to the investigation of an array of pharmacotherapies to stop the panic attacks.

The approach of cognitive behavioral therapy (CBT) is different. “The goal is not so much to get rid of the attacks but to help patients become less afraid of them because when a person becomes less afraid, he or she has fewer attacks,” Dr Pollard noted.

Agoraphobia and Panic Disorder

The relationship between agoraphobia and panic has gone through some changes and reconceptualization, as evidenced by the diagnostic categories laid out in the Diagnostic and Statistical Manual of Mental Disorders (DSM). In DSM-III,¹⁰ agoraphobia without panic attacks was conceptually different from agoraphobia with panic attacks.¹¹ In DSM-III-R,¹² however, although the distinction between agoraphobia with and without panic was dropped, agoraphobia without a history of panic disorder still remained a separate diagnosis that could be coded as such.

One of the changes in DSM-5¹³ was that panic disorder and agoraphobia were separated again, and criteria were added to distinguish agoraphobia from specific phobia.¹¹ Thus, the situations are feared and avoided because the person believes that escape might be difficult or help might not be available in the event of several distressing symptoms (eg, incontinence), not only panic.¹¹ However, panic attacks are a potential specifier.

DSM-5 Diagnostic Criteria for Agoraphobia include the following:¹³

• Intense fear or anxiety prompted by the actual or predicted exposure to 2 or more of the following situations:
  
  • Using public transportation
  • Being in open areas
  • Being in closed-off areas
  • Standing in line or a crowd
  • Being alone outside of the house
• He or she avoids the above situations because the individual believes they may become stuck or help might be unavailable in the event that the individual begins to panic.
• The listed situations usually incite fear or anxiety.
• The listed situations are avoided, require help from a loved one, or are endured with a strong fear.
• The fear the individual has is out of proportion to the possibility of danger.
• The fear or avoidance is persistent, as it typically lasts for at least 6 months or longer.
• The fear or avoidance causes the individual significant distress.
• If another medical condition exists alongside of this disorder, the fear or avoidance is undoubtedly excessive.
• The fear of avoidance is not better explained by the symptoms of another medical disorder or a situational circumstance.

“Agoraphobia involves the fear of some type of attack that can come out of the blue, and encompasses not only panic but also fainting, loss of bladder control, vomiting, or even migraine headaches,” Dr Pollack observed, adding that there is still disagreement about “how to best categorize the development of phobic responses around other types of symptom attacks.”

“What these have in common is that they are perceived by the person as overwhelming and unpredictable and very intense, but we tend to see it as another kind of agoraphobia,” he said.

Although incontinence and migraine are medical conditions, the response in agoraphobia is exaggerated in terms of what is medically recommended by a physician.

He noted that what is unique about panic attacks is that they are generally unexpected. “A person with arachnophobia may be afraid of spiders but will panic only when he or she sees a spider and also won’t be worried about the symptoms during the panic, such as lightheadedness or racing heart, in that setting.”

In contrast, someone with agoraphobia does not know why the panic attack suddenly came on; for example, at the grocery store. “The patient thinks, ‘I know I’m not afraid of grocery stores, so why am I having this attack?’ Patients worry that they are losing control or having a heart attack,” Dr Pollack said.

So while they are not afraid of the store per se, they become afraid of having an attack in the store and begin to avoid going shopping.

Behavioral and Pharmacotherapeutic Approaches

Several classes of medication are used for addressing symptoms of panic disorder, including selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, monoamine oxidase inhibitors, and benzodiazepines.¹⁴

Table 1: Pharmacotherapies for Panic Disorder in Adults¹⁵

Class	Agent
SSRIs	Citalopram Escitalopram Fluoxetine Fluvoxamine Paroxetine Sertraline
Selective serotonin norepinephrine reuptake inhibitors	Duloxetine Venlafaxine
Tricyclic antidepressants	Clomipramine
Calcium modulator	Pregabalin
Benzodiazepines	Lorazepam melting tablets as needed for acute panic attacks
Azapirone	Buspirone
Reversible monoamine oxidase A inhibitor	Moclobemide

^{*Consider risk/benefits carefully and use only for limited period; can be used in combination with SSRIs and SNRIs during the first weeks before the onset of antidepressant efficacy.}

The most well-researched psychotherapeutic approach is CBT with clinical gains maintained at 2-year follow-up.¹⁶ A meta-analysis of 124 studies found that CBT was at least as effective as pharmacotherapy and in some trials even significantly more effective.¹⁷ Another review found that CBT is at least as effective as pharmacotherapy for panic.¹⁴

The neurobiological effect of CBT can be seen on magnetic resonance imaging. A study¹⁶ comparing CBT with SSRIs and SNRIs found that both treatments led to a significantly greater reduction in panic attacks, depression, and general anxiety than those experienced by the waitlist control group. However, CBT had a significantly greater decrease in avoidance, fear of phobic situations, and anxiety symptoms based on self-report scales. It also yielded great reduction in bilateral amygdala activation, compared with the SSRI/SSNRI and waitlist groups.¹⁸

Combining pharmacotherapy with CBT has been found to be superior to either treatment alone during acute-phase treatment. However, long-term studies of treatments that combine pharmacotherapy with CBT for panic disorder with or without agoraphobia have found little benefit for these combinations vs monotherapies.¹⁹ 

“Medication and CBT can both stop panic attacks and reduce avoidance in the short run,” Dr Pollack noted. “But CBT was superior to medication in the long run, with lower rates of relapse.”

Dr Pollack regards CBT as “the frontline treatment” of agoraphobia. “We tell our patients that the preferred treatment is CBT alone, if they can handle it.”

However, if the patient is unwilling or unable to try CBT without medication, “I would not suggest withholding medication,” he emphasized.

CBT plays an important role even in patients who have opted for pharmacotherapy at several particularly critical points in therapy.

“The risk of relapse is highest when patients are tapering off their medications, and CBT can be extremely helpful at that time,” he noted.

It can also be helpful when the person is going through a stressful situation, “since a precursor to the development of panic attacks can be substantially stressful life events, both positive and negative.”

In addition, CBT can be used in the event of “breakthrough” panic attacks that sometimes occur, even when a person has been taking medication successfully. “If the medication has been working but a panic attack happened anyway, this can be a common time for potential relapse.”

Tips for Psychiatrists

In a “fairly mild case” of agoraphobia, whether or not medication is prescribed, psychiatrists can consider recommending books or reliable organizations (eg, the Anxiety and Depression Association of America) to patients who do not wish to attend formal CBT sessions.

He suggested that instead of advising patients to wait until the medication works to begin experimenting with going out, clinicians should encourage them to begin the anti-avoidance process immediately.

Although ultimately, the ideal for patients is to be able to function independently, if they need to bring a family member of friend at first, they can do so, he said.

“You can suggest that they begin gradually, at a pace that they can handle, taking it easy and going one step at a time,” he said.

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