Anxiety attacks
Fear attacks

INCIDENCE (IN U.S.): 1% 1-mo incidence of panic attacks
PREVALENCE (IN U.S.):
• 15% lifetime prevalence of panic attacks
• Panic disorder much more uncommon, with a lifetime prevalence of 1.5% to 3.5%; chronicity of condition reflected by a similar 1-yr prevalence rate of 1% to 2%
• Agoraphobia relatively rare; 0.3% to 1% lifetime prevalence
PREDOMINANT SEX:
• Women more commonly affected (>85% of clinical population)
• Panic disorder twice as common in women
• Panic disorder with agoraphobia three times as common in women
PREDOMINANT AGE:
• Age of onset earlier in males (24 yr) than females (28 yr)
• Onset after age 45 yr rare
PEAK INCIDENCE:
• Chronic condition with a waxing and waning course
• Bimodal incidence peaks noted, with the first peak between ages 15 and 24 yr and second peak between 35 and 44 yr
GENETICS:
• Risk of developing panic disorder in first-degree relatives of individuals with panic disorder four to seven times that of general population
• Findings in twin studies: about 60% of contributing factors to panic are genetic

1.Present either with a panic attack or with fear and anxiety related to anticipation of a future panic attack
2.Typical presentation: unexpected, untriggered periods of intense anxiety and fear with associated physiologic changes (e.g., palpitations, sweating, tremulousness, shortness of breath, chest pain, GI distress, faintness, derealization, paresthesia)
3.Emergency or physician visits often occasioned by physical symptoms

1.Rare complaints to physician
2.Activities usually self-limited by avoiding public situations where the patient might experience a panic attack and would be unable to exit readily, such as the following:
Crowded public areas (stores, public transportation, church)

Individual interactions (hair dresser, neighborhood meetings)

1.On exposure to or anticipation of exposure to such situations, significant anxiety occurs

Hypotheses (note: There are sufficient data to support each model.)

1.Central dyscontrol of autonomic arousal (typically localized to the locus ceruleus)
2.Cognitive overreaction to relatively mild physiologic cues
3.Dysfunction of a central suffocation alarm mechanism

• Medical conditions
1.Arrhythmias
2.Hyperthyroidism
3.Hyperparathyroidism
4.Seizure disorders
5.Respiratory diseases
6.Pheochromocytoma
• Therapeutic (theophylline, steroids) and recreational (cocaine, amphetamine, caffeine) drugs and drug withdrawal (alcohol, barbiturates, benzodiazepines)
• Phobias (e.g., specific phobia or social phobia)
• Obsessive-compulsive disorder (cued by exposure to the object of the obsession)
• Posttraumatic stress disorder (cued by recall of a stressor)

• Emergency presentation: cardiac, re-spiratory, or neurologic symptoms
• History and physical examination to rule out a concomitant medical condition
NOTE: Panic disorder and agoraphobia are not diagnoses of exclusion, but exclusion of other conditions is usually required.

• Thyroid profile
• Electrolyte measures, including calcium
• Toxicology screen
• ECG
• Acute cases: possible monitoring and cardiac enzymes to rule out arrhythmia or ischemia

• For temporal lobe dysfunction (e.g., temporal lesions or as ictal or interictal manifestation of temporal lobe seizures): brain CT scan or MRI and/or an EEG in some patients
• Holter monitor to rule out occult or episodic arrhythmias
• Chest x-ray examination, ABG, or pulmonary function tests if respiratory compromise suspected

• Psychotherapy: generally very effective; long-term follow-up studies of panic patients suggest that therapy is possibly superior to pharmacologic interventions
• Interpersonal and cognitivebehavioral therapy modalities: most extensively studied

• Benzodiazepines, particularly alprazolam: very effective in acute setting
• Low-dose alprazolam for patients with rare panic attacks and asymptomatic interattack periods (0.25 to 0.5 mg PO or sublingually prn)

• Because disorder patients, as a group, have a low likelihood of abusing benzodiazepines, uncomplicated cases managed with low-dose benzodiazepines on a schedule or prn
• Preferred pharmacologic agents: antidepressants with a significant serotonin reuptake inhibitory action
• Imipramine quite effective in both panic disorder and agoraphobia
• Newer antidepressants (paroxetine, sertraline, and fluoxetine) quite effective in preventing panic attacks and ameliorating agoraphobia

• Typical course chronic but with significant waxing and waning (common to have long periods of remission)
• Presence of agoraphobia associated with a more chronic course
• Findings with long-term follow-up studies: 6 to 10 yr after treatment some 30% in remission, 40% to 50% improved with residual symptoms, and the remainder either unchanged or worse
REFERRAL
Referral needed if:
• Patients do not respond to a serotonin reuptake inhibitor
• Therapy is the preferred treatment

Mavissakalian MR, Perel JM: Duration of imipramine therapy and relapse in panic disorder with agoraphobia. J Clin Psychopharmacol 22:294, 2002.

Pohl RB et al: Sertraline in the treatment of panic disorder: a double-blind multicenter trial, Am J Psychiatry 155:1188, 1998.

Rapaport MH et al: Sertraline treatment of panic disorder: results of a long-term study, Acta Psychiatr Scand 104:289, 2001.