Introduction

Panic Disorder is a part of a spectrum of anxiety disorders that include Generalized Anxiety Disorder (GAD), phobias, Obsessive-Compulsive Disorder (OCD), and Posttraumatic Stress Disorder (PTSD) (American Psychiatric Association, 2000). Panic Disorder is a debilitating psychological and emotional disorder that is marked by a heightened sense of anxiety or panic (Dattilio, 2001; Hanisch, Hantsoo, Freeman, Sullivan & Coyne, 2008). In adults, Panic Disorder is estimated to affect anywhere from 4% (Dattilio) to 5% of the U.S. population (Roy-Byrne, Craske & Stein, 2006). In Europe, it is estimated that the spectrum of anxiety disorders that include Panic Disorder rank as the most prevalent of all mental disorders with an adult incidence of 12% per year (Andlin-Sobocki & Wittchen, 2005). In Hong Kong, the 1-year prevalence rate for Panic Disorder is 3.89% (Lee, Tsang & Kwok, 2005).

In the US, the economic cost of anxiety disorder in 1990 is estimated to be $42.3 billion or $1,542 per sufferer. Of this estimate, Panic Disorder and Posttraumatic Stress Disorder (PTSD) exerted the most toll (Greenberg et al., 1999). Panic Disorder is associated with an increase in the use of health care services including hospitalization, emergency room visits, medical consultations with specialists (Marciniak et al., 2005), and increase in absenteeism from the workplace and/or decline in workplace productivity (Greenberg et al.).

Further exacerbating the impact of Panic Disorder on the individual suffering from Panic Disorder and the economy, Panic Disorder can lead to maladaptive behaviors such as cigarette smoking (Zvolensky & Bernstein, 2005), alcoholism (Lotufo-Neto & Gentil, 1994) and drug abuse (Ham, Waters & Oliver, 2005; Roy-Byrne, Craske & Stein, 2006). Paradoxically, while research has found that maladaptive behavior such as cigarette smoking and alcoholism may actually contribute and at times increase the likelihood of Panic Disorder, people with Panic Disorder often do so in an attempt to alleviate symptoms of Panic Disorder or escape recurrence of panic attacks (Abrams et al., 2008; Lotufo-Neto; McLeish, Zvolensky, Bonn-Miller & Bernstein, 2006; Zvolensky).

Given the cost imposed upon by Panic Disorder on the economy (Greenberg et al., 1999), a study of possible early intervention becomes necessary to minimize the impact of Panic Disorder on the sufferer as well as on the economy. While there has been numerous research studies conducted on adults, little significant research has been conducted on the prevalence of Panic Disorder on children and adolescents. This paper proposes, therefore, to extrapolate upon research outcomes from studies conducted on the adult population and assess the applicability of known successful interventions to children and adolescents.

Diagnostic Features of Panic Disorder

According to the American Psychiatric Association's Diagnostic Statistical Manual of Mental Disorders (DSM-IV-TR) (2000), panic attacks are marked by the sudden, and without warning, occurrence of at least four of the following symptoms: (a) shortness of breath or smothering sensation; (b) dizziness, unsteady feelings, or faintness; (c) palpitations or accelerated heart rate; (d) trembling or shaking; (e) sweating; (f) choking; (g) nausea or abdominal distress; (h) depersonalization or derealization - a feeling that the sufferer's body or environment, respectively, is not real; (i) numbness or tingling sensations; (j) hot flashes or chills; (k) chest pain or discomfort; (l) fear of dying; (m) fear of going crazy or losing self-control. To qualify for a panic attack, the symptoms cannot be attributed by the individual to situational stimuli and that the panic attack must peak within ten minutes.

Panic attacks often are triggered by sudden internal stimuli, e.g., heart pounding, muscle twitching, or hand shaking (Ham et al., 2005). Individuals with Panic Disorder associate these internal physical sensations with over-exaggerated fear of catastrophe such as having a heart attack, going crazy or social embarrassment (Barlow, 1992; Doerfler, Connor, Volungis & Toscano, 2007; Hofmann et al., 2007). At other times, however, the source of panic attack can come from external stimuli such as mild ground vibration. Those with Panic Disorder, like those who over-exaggerate the meaning of internal stimuli, interpret their environmental stimuli catastrophically. Without looking for the source of the ground shaking (possibly trash truck collecting trash), those with Panic Disorder may interpret the event as the beginning of a major earthquake (Hofmann et al.).

People who experience panic attacks feel a sense of extreme danger and doom and experience a strong fight or flight response (Hanisch et al., 2008). The panic attack may be interpreted as sign that the person is dying and that the symptoms are indicative of underlying and undiagnosed physiological problems, the person fears losing his mind or control of his environment (Barlow, 1992).

After the first few occurrences of panic attack, people who eventually develop Panic Disorder begin to have intense worry about the next time an attack will happen (Sainz, 2007; Perugi, Frare & Toni, 2007). Oftentimes, as a result of multiple experiences with panic attacks in certain situations and places, agoraphobia can develop. Agoraphobia is characterized by fear of public places or situations when opportunity to escape would be minimal or unlikely (Perugi et al.). Believing that certain places or situations can trigger panic and avoidance of these places and situations would minimize occurrence of panic attacks, many people who suffer from Panic Disorder and Agoraphobia at times become prisoners in their own homes for long periods of time (Bouton, Mineka & Barlow, 2001; Hanisch et al.). However, it is not uncommon to have Panic Disorder without Agoraphobia.

A manifestation of Panic Disorder that supports the claim that panic attack in individuals with Panic Disorder occurs outside of the individual's consciousness is the phenomena of nocturnal panic. While the majority of panic attacks occur during the day, nocturnal panic occur at night when the person is asleep (Albert, Maina, Bergesio & Bogetto, 2005; Den Boer, 1997). Nocturnal panic is a typical experience for people suffering from Panic Disorder with 71% reporting nocturnal panic (Albert et al.; Merritt-Davis & Balon, 2003). However, nocturnal panic is not well understood and questions remain whether nocturnal panic, in fact, is a more severe manifestation of Panic Disorder or a disability unique from Panic Disorder with different underlying causes and pathology (Merritt-Davis & Balon, 2003).

Experiencing a panic attack in itself, however, does not qualify a person for the diagnosis of Panic Disorder (Bouton et al., 2001). To be diagnosed with Panic Disorder, a panic attack must be followed by at least a month of recurring concerns of having another attack, fear that the panic may be indicative of underlying physiological problems and/or repercussions of the panic attacks, and changes in behavior as a result of the attacks. (American Psychological Association, 2000.)