According to some theories, many situations that can trigger panic attacks were truly dangerous earlier in human evolution. For example, being trapped in a tunnel could lead to suffocation or collapse; heights might be dangerous; in open fields, an individual was more susceptible to predators (such as lions or wolves); public places might have brought our ancestors into contact with hostile strangers. Many of the fears involved in panic disorder and agoraphobia are reminiscent of these earlier instinctive and adaptive fears. However, these situations are not dangerous today.
Research does demonstrate that panic disorder and agoraphobia have some genetic links, but they are not entirely inherited. In any given year, 30% to 40% of the general population will have a panic attack. However, most of these people will not interpret their panic as a signal of catastrophic danger, and thus will not go on to develop panic disorder or agoraphobia.
Initially, a panic attack is usually activated by a stressful situation, such as leaving home, marital/ couple conflict, surgery, new responsibilities, or physical illness. These sensations of physical arousal (heavy breathing, sweating, dizziness, pounding heart, and so on) may be misinterpreted as signals of catastrophic danger — for example, a person may focus on the increase in heart rate and jump to the conclusion that he or she is about to have a heart attack. As a result, the person may develop “hypervigilance” (that is, an excessive focus on physical sensations), which can result in increased arousal (increased physical sensations and worry). This arousal triggers further catastrophic misinterpretations, which we call “false alarms” because they signal that danger is imminent when it really is not. A full-blown panic attack can result from such arousal and misinterpretations. Consequently, the person develops “anticipatory anxiety” (fear that panic attacks will continue to occur) and begins to avoid situations that give rise to such anxiety — especially if escape from these situations may be difficult or embarrassing, or if help may not be readily available. In fact, when avoidance and escape become the major coping mechanisms used to handle anxiety, the person has developed agoraphobia.
An individual with agoraphobia who does not avoid feared situations altogether usually enlists the aid of a “safety person”-that is, a person who accompanies the individual into these situations in case the anxiety becomes too great and the individual needs to escape. Even though reliance on the “safety person,” avoidance, and other “safety behaviors” may mean that the individual has had no panic attacks in months, he or she often lives in fear of the next attack. The world becomes smaller and smaller as a result of the individual’s fear and avoidance. Partly because of this constriction in their lives, and partly because they feel out of control and are unsure how to handle their problem, many people with panic disorder and agoraphobia also develop depression. Some of these people become so anxious and depressed that they self-medicate with alcohol, Valium, or Xanax.