The condition often runs in families, and stressful or traumatic events such as the death of a parent or being attacked may be a trigger.Research has uncovered a link between agoraphobia and difficulties with spatial orientation. Individuals without agoraphobia 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. In a virtual reality study, agoraphobics showed impaired processing of changing audiovisual data in comparison with subjects without agoraphobia. Substance-induced
Chronic use of tranquilizers and sleeping pills such as benzodiazepines has been linked to onset of agoraphobia. In 10 patients who had developed agoraphobia during benzodiazepine dependence, symptoms abated within the first year of assisted withdrawal. Similarly, alcohol use disorders are associated with panic with or without agoraphobia; this association may be due to the long-term effects of alcohol consumption causing a distortion in brain chemistry. Tobacco smoking has also been associated with the development and emergence of agoraphobia, often with panic disorder; it is uncertain how tobacco smoking results in anxiety-panic with or without agoraphobia symptoms, but the direct effects of nicotine dependence or the effects of tobacco smoke on breathing have been suggested as possible causes.
Self-medication or a combination of factors may also explain the association between tobacco smoking and agoraphobia and panic. Attachment theory
Some scholars have explained agoraphobia as an attachment deficit, i.e., the temporary loss of the ability to tolerate spatial separations from a secure base. Recent empirical research has also linked attachment and spatial theories of agoraphobia. Spatial theory
In the social sciences, a perceived clinical bias exists in agoraphobia research. Branches of the social sciences, especially geography, have increasingly become interested in what may be thought of as a spatial phenomenon. One such approach links the development of agoraphobia with modernity. Factors considered contributing to agoraphobia within modernity are the ubiquity of cars and urbanization. These have helped develop the expansion of public space and the contraction of private space, thus creating in the minds of agoraphobia-prone people a tense, unbridgeable gulf between the two. Evolutionary psychology
An evolutionary psychology view is that the more unusual primary agoraphobia without panic attacks may be due to a different mechanism from agoraphobia with panic attacks. Primary agoraphobia without panic attacks may be a specific phobia explained by it once having been evolutionarily advantageous to avoid exposed, large, open spaces without cover or concealment. Agoraphobia with panic attacks may be an avoidance response secondary to the panic attacks, due to fear of the situations in which the panic attacks occurred. Diagnosis
Most people who present to mental health specialists develop agoraphobia after the onset of panic disorder.