trollable screaming or crying) may be seen; however, such symptoms  should not count as
one of the four required symptoms. Panic attacks can occur in the context of any mental
disorder (e.g., anxiety disorder s, depressive disorders, bipola r disorders, eating disorders,
obsessive-compulsive and related disorders, personality di sorders, psychotic disorders,
substance use disorders) and some medical cond itions (e.g., cardiac,  respiratory, vestibu-
lar, gastrointestinal), with the majority ne ver meeting criteria for panic disorder. Recur-
rent unexpected panic attacks are requir ed for a diagnosis of panic disorder. 
Associated Features 
One type of unexpected panic attack is a nocturnal panic attack  (i.e., waking from sleep in a
state of panic), which differs from panicking after fully waking from sleep. Panic attacks
are related to a higher rate of  suicide attempts and suicidal ideation even when comorbid-
ity and other suicide risk fa ctors are taken into account.
Prevalence
In the general population, 12-month prevalen ce estimates for panic attacks in the United
States is 11.2% in adults. Twelve-month preval ence estimates do not appear to differ sig-
nificantly among African Americans, Asian Americans, and Latinos. Lower 12-month
prevalence estimates for European countries ap pear to range from 2.7% to 3.3%. Females
are more frequently affected than males, al though this gender difference is more pro-
nounced for panic disorder. Panic attacks can oc cur in children but are relatively rare until
the age of puberty, when the prevalence rates increase. The prevalence rates decline in
older individuals, possibly reflecting diminishing severity to subclinical levels.
Development and Course
The mean age at onset for panic attacks in the United States is approximately 22–23 years