In both the ICD-10 and DSM-IV diagnostic classifications PD is considered as an anxiety disorder. Although these classificatory systems do not represent the last word in mechanistic understanding of behavioural disorders, it is clear from the inclusion of PD within the anxiety disorder/neurotic disorder grouping that the general view is that PD has a psychological rather than a biological aetiology. However, whilst it is clear that the core subjective experience of PD is one of extreme fear, this does not in itself prove that the disorder is simply an extreme end of a continuum that starts with mild anxiety.
Panic attacks may (in common with epileptic seizures) be described as paroxysmal events. They are discrete periods of intense fear or emotional discomfort, accompanied by a range of somatic symptoms including palpitations, trembling, a feeling of shortness of breath (which may be associated with hyperventilation), sweating, feelings of choking and psychological symptoms including depersonal-ization, fear of losing control and fear of dying. The attacks occur spontaneously, without warning, and although they may occur in situations in which they have previously occurred, when the patient is concerned that an event may happen, they may also occur unexpectedly. Individual panic attacks are self-limiting although estimates of duration vary. Retrospective estimates by sufferers suggest an average duration of between 10 and 20 minutes. However, a prospective study reported considerably longer attacks, with a mean of between 15 and 50 minutes (Taylor et al., 1986). Whilst some people experience attacks accompanied by most if not all of the associated symptoms described above, in others there may be very few experienced apart from paroxysmal fear and anxiety. The frequency of attacks varies, both between individuals, and over time within individuals, from several attacks in a day to only occasional attacks over a whole year.
The clinical diagnosis of PD is characterized by panic attacks, avoidance of situations in which previous panic attacks have occurred and ongoing worry regarding the possibility of future attacks. However, these recurrent attacks of extreme fear and a feeling of impending death or disaster are not restricted to any particular environmental setting or set of circumstances. In addition, it is important to note that although patients with PD worry about having further panic attacks, this worry is of a lower magnitude than the emotions experienced during an attack.
There is good evidence, based on clinical accounts, that PD is not a homogeneous disorder. In some people pure PD exists with panic attacks in the absence of any other psychopathology. However, sizeable proportions of those with PD are comor-bid for agoraphobia or depression or both. It has been reported that women with PD are more likely to report depression, anxiety or agoraphobic avoidance than men with this diagnosis (Chambless and Mason, 1986). Increased anxiety and depression in affected women was also noted by Oie et al. (1990). Whilst women may show greater agoraphobic avoidance, men may increase their alcohol intake to cope with their symptoms. Although these differences in the associated symptoms and behaviours between the manifestations of PD in men and women exist, the core features of panic attacks appear to be relatively similar across the sexes. Hence, although in therapeutic terms it is clearly important to consider the whole syndrome with which the patients present, in mechanistic terms it may be that both sexes share a common aetiology of panic attacks, but that cultural and behavioural responses to these attacks then determine the sex differences in associated symptoms.
In a large American epidemiological study, the National Comorbidity Survey, it was found that the prevalence of PD was greatest in the age range 15-25 (Eaton et al., 1994). However, separating data from males and females revealed that whilst peak age of onset was within this range for males, for females it was older. This study also noted that people with less than 12 years of education were up to ten times more likely to suffer from PD than those with more than 16 years of education (i.e. including a college education).
Perhaps surprisingly, in recent years it has become clear that panic attacks are associated with an increased risk of attempted and completed suicide (Markowitz et al., 1989). The rate of suicide attempts is reported as 20% in those with PD and 12% in those with panic attacks but without the avoidance of panic-inducing situations and anxiety regarding future attacks that contribute to the diagnosis of PD. In this context it is also noted that there is an increased risk of suicide and attempted suicide in people with epilepsy, as discussed by Blumer (Chapter 8).
Was this article helpful?