Panic Disorder 281
encing a panic attack while waiting in a bank line or attending the movies. As Taylor
(2000) noted, many factors can determine whether a situation increases the probability
of a panic attack including temperature, access to exits, crowding, familiarity, and the
like.
The distinction between uncued versus cued panic has important diagnostic impli-
cations in distinguishing panic disorder from other types of anxiety disorders. Although
panic attacks are present in the majority of anxiety disorders (over 80%), they are usually
associated with specific situations (e.g., anticipation of or exposure to a social encounter
in social phobia; see review by Barlow, 2002). For this reason DSM-IV-TR (APA, 2000)
requires the presence of at least two uncued or spontaneous panic attacks in order to
make a diagnosis of panic disorder. However, it can be difficult to determine if a panic
episode is entirely unexpected because we are dependent on the client’s retrospective
report and observational skills (McNally, 1994). The unexpectedness of panic probably
falls along a continuum, thereby making it difficult to assign panic attacks to a discrete
category of either expected or unexpected. Moreover, truly unexpected, uncued panic
attacks may be relatively infrequent, even in panic disorder (Brown & Deagle, 1992;
Street, Craske, & Barlow, 1989).
Clinician Guideline 8.2
Assessment for panic disorder should include a thorough evaluation of the frequency, sever-
ity, subjective probability, and contextual factors associated with spontaneous and situation-
ally cued panic attacks.Nocturnal Panic Attacks
Nocturnal panic attacks (NPs) are a frequent occurrence, with 25–70% of individuals
with panic disorder reporting at least one sleep panic attack, and 18–33% reporting fre-
quent, recurrent NPs (Barlow, 2002; Craske & Rowe, 1997; Mellman & Uhde, 1989).
NPs, though phenomenologically similar to daytime panic attacks (Craske & Rowe,
1997), are characterized by an abrupt waking from sleep in a state of panic, especially
during the transition from Stage 2 to Stage 3 sleep (Barlow, 2002; Hauri, Friedman,
& Ravaris, 1989; Taylor et al., 1986). NPs are distinct from other sleep- related con-
ditions such as night terrors, sleep apnea, sleep seizures, or sleep paralysis (Craske,
Lang, Aikins, & Mystkowski, 2005). There is some evidence that individuals with NPs
have more severe panic attacks than those with panic disorder without NPs, and many
patients with frequent NPs become fearful of sleep (Barlow, 2002; Craske & Rowe,
1997).
Craske and Rowe (1997; see also Aikins & Craske, 2007) proposed that the same
cognitive factors responsible for panic attacks in wakefulness are implicated in NPs.
Thus fear of change in physical state during sleep or relaxation, heightened vigilance
for and perception of changes in bodily state, and catastrophic appraisal of physiologi-
cal changes immediately upon waking are considered important in the pathogenesis of
NPs. In NP distress about sleep and relaxation may reflect a fear of losing vigilance
for bodily changes during sleep (Aikins & Craske, 2007). In support of this cognitive-