Panic Disorder

Snapshot

• A 25-year-old woman with no significantly past medical history presents to the physician with concern about having recurrent panic attacks in the past 2 months. She describes that during an episode, she becomes overcome with a sense of doom within minutes and her breath becomes quick and shallow. She says she feels her heart racing, her palms getting sweaty, and feelings of lightheadedness. The attacks occur once or twice a week and have no identifiable trigger. Between episodes, she admits to a strong fear of another attack occurring, and she is considering taking time off from work because she is worried that she may have an episode during a meeting with her boss.

Introduction

• Overview
  • panic disorder is characterized by recurrent panic attacks associated with > 1 month of subsequent persistent worry about having another panic attack or behavioral changes related to the attack 
• Epidemiology
  • prevalence
    • 2-6% of adults in the US
  • demographics
    • women are 2-3 times more likely to have panic disorder
    • most commonly develops between 18-45 years of age
  • risk factors
    • asthma linked to a 4.5 ↑ in risk of developing panic disorder
• Pathophysiology
  • panic disorder is a psychiatric disorder that may be caused by neurochemical dysfunction
  • symptoms arise from sympathetic overdrive
• Genetics
  • study of panic disorder in first-degree relatives revealed heredity of ~43%
• Associated conditions
  • major depression
  • schizophrenia
  • obsessive-compulsive disorder
  • phobias
  • cluster C personality disorders 
• Prognosis
  • long-term prognosis is good with ~65% of patients achieving remission within 6 months
  • negative prognostic variables
    • low socioeconomic status
    • severe illness at time of initial assessment
• high interpersonal sensitivity

Presentation

• Symptoms
  • 4 or more panic attacks in a 4-week period or ≥ 1 panic attacks followed by at least 1 month of fear of another panic attack 
  • panic attack symptoms may include
    • intense fear of dying and discomfort
    • sympathetic overdrive
      • sweating
      • palpitations
      • abdominal distress/nausea
      • hyperventilation
    • paresthesias
    • light-headedness
    • chest pain
    • chills
    • choking
    • disconnectedness/loss of reality
    • shaking
  • panic attack symptoms have no precipitating stimulus and often peak within 10 minutes and last 20-30 minutes from onset
  • panic attacks may be triggered by injury, illness, interpersonal conflict or loss, cannabis use, or stimulants (i.e., caffeine or decongestants)
• Physical exam
  • anxious mood
  • nonspecific signs of ↑ sympathetic state
    • hypertension
    • tachycardia
    • mild tachypnea
    • mild tremors
• cool and clammy skin

Studies

• ECG
  • rule out ischemia, infarction, or pericarditis in patients with chest pain
• TSH, T3, and T4
  • rule out hyperthyroidism
• Urine toxicology screen
• screen for amphetamines, cannabis, cocaine, and phencyclidine in patients suspected of intoxication from substance use

Differential

• Acute coronary syndrome
  • key distinguishing factor
    • ECG changes
      • i.e., ST-elevations, Q waves, and T-wave inversion
• Asthma
  • key distinguishing factor
    • wheezing on physical examination
• Hyperthyroidism
  • key distinguishing factor
• ↑ levels of thyroid hormones

Treatment

• Lifestyle
  • psychotherapy
    • cognitive-behavioral therapy (CBT)
      • treatment of choice
      • consider for all patients
• Medical
  • benzodiazepines (i.e., alprazolam or clonazepam)
    • indications
      • providing a few doses for emergency or for urgent/as-needed use may ↑ patient confidence
      • avoid in patients with known history of substance use disorder or alcoholism
  • selective serotonin reuptake inhibitors (i.e., escitalopram or sertraline)
    • indications
• long-term pharmacological management

Complications

• Noncompliance or adverse medication effects
  • ↑ 4-fold in patients with panic disorder
  • treatment expectations and concerns should be discussed with the patient
• Agoraphobia