Panic disorder

• recurrent unexpected panic attacks
• in the absence of triggers
• marked by persistent concern about additional panic attacks
  • losing control
  • having a heart attack
  • “going crazy”
• maladaptive change in behaviour related to the attacks
  • behaviors designed to avoid having panic attacks
  • such as avoidance of exercise or unfamiliar situations
  • restricting usual activities
  • avoiding agoraphobia-type situations
  • reorganizing routines to ensure that help is available in the event of a panic attack
  • severe restrictions on food intake or medications for fear it may trigger attacks
• not attributable to the physiological effects
  • of a substance
    • a drug of abuse – cocaine, amphetamines, caffeine, withdrawal from alcohol
    • a medication
  • another medical condition 
    • hyperthyroidism
    • cardiopulmonary disorders ((e.g. – arrhythmias, atrial fibrillation, flutter, palpitations, dyspnea, syncope, supraventricular tachycardia)
    • pituitary disease
    • Pheochromocytomas – headache, excessive sweating, and palpitations
• between 1/3 to 1/4 of individuals may also have nocturnal panic attacks that wake them from sleep

• Epidemiology
  • It affects 2 females for every 1 male
  • Average age 20-24 years
  • The rates of panic disorder gradually increase in adolescence and peak during adulthood
  • Panic disorder also commonly cooccurs with agoraphobia
    

Prognosis

• Youth with panic attacks may go on to develop
  • mood disorders such as bipolar disorder and major depressive disorder
  • other anxiety disorders
  • eating disorder
  • psychotic disorders
  • personality disorders
• can have a negative impact on
  • physical and psychological function
  • to stress on the individual’s interpersonal functioning
• has a chronic waxing and waning course over the individual’s lifetime
• Individuals with panic disorder are at a higher risk for suicide

Risk Factors

• Adverse childhood experiences can increase the risk for panic disorder
• Smoking
• stressor in the months prior to their panic attack.
• patients with medical conditions – thyroid disease, cancer, chronic pain, cardiac disease, irritable bowel syndrome, migraine, as well as allergic and respiratory diseases

Screening and Rating Scales

• Panic Disorder Severity Scale (PDSS) – 7 question scale to grade panic disorder severity.

History

• During the past two weeks how much have you been bothered by
• the following problems?
  • Feeling nervous, anxious, frightened, worried, or on edge
  • Feeling panic or being frightened
  • Avoiding situations that make you anxious
• Physical Exam
  • Cardiac, respiratory, and abdominal exam should be performed according to the clinical presentation.

investigations

1. Bloods
   1. Complete blood count
   2. Fasting glucose
   3. Fasting lipid profile (TC, vLDL, LDL, HDL, TG) 
   4. Thyroid-stimulating hormone
   5. Electrolytes
   6. Liver enzymes
   7. If warranted
      1. Urine toxicology for substance use
      2. plasma metanephrines (95% sensitivity)
      3. 24-hour urinary metanephrines (99% sensitivity)
      4. abdominal MRI (100% sensitivity, pheochromocytomas demonstrate a distinctive appearance)
      5. abdominal CT
      6. persistent vital sign changes🡪  consider a pulmonary embolism work up and order D-dimer
2. ECG
   1. signs of ventricular preexcitation (short PR and delta wave)
   2. for short or long QT interval in patients with palpitations
   3. for signs of ischemia, infarction, or pericarditis patterns

Treatment

• During the acute phase (i.e. – first 4 to 12 weeks), combination
  • cognitive behavioural therapy with exposure and 
  • medication 

should be offered (as medication may be especially helpful in cases where symptoms are too distressing for patients to be able to do exposure therapy)

• During the follow up and recovery phase, combination therapy is superior to medications alone.
• Similarly, CBT alone is as effective as doing combination therapy during this phase.
• At the three year follow up point in some studies, the benefits of CBT are still maintained, whereas they are not maintained in medication-only treatment.

First-line	Citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, paroxetine CR, sertraline, venlafaxine XR
Second-line	Alprazolam, clomipramine, clonazepam, diazepam, imipramine, lorazepam, mirtazapine, reboxetine
Third-line	Bupropion SR, divalproex, duloxetine, gabapentin, levetiracetam, milnacipran, moclobemide, olanzapine, phenelzine, quetiapine, risperidone, tranylcypromine
Adjunctive therapy	Second-line: alprazolam ODT, clonazepam Third-line: aripiprazole, divalproex, olanzapine, pindolol, risperidone
Not recommended	Buspirone, propranolol, tiagabine, trazodone

CR = controlled release; ODT = orally disintegrating tablets; SR = sustained release; XR = extended release.

Benzodiazepines

• There is evidence to suggest that adding benzodiazepines to psychotherapy may be worse than doing therapy alone
• should NOT be
  • given to those with a previous or current history of substance abuse.
  • used as first-line agents
• reserved for patients whose symptoms have not responded to other treatments.
• Benzodiazepines may have a favourable adverse effect profile in the management of treatment-refractory anxiety disorders, compared with atypical antipsychotic agents.
• Adverse effects
  • cognitive impairment
  • falls and sedation
  • tolerance and dependence 
  • potential for abuse