A 32-year-old woman from Delhi presents to the psychiatry outpatient department with a 2-year history of sudden, unpredictable episodes of intense fear lasting 10–20 minutes. During these episodes, she experiences palpitations, diaphoresis, trembling, dyspnea, chest discomfort, and a fear of dying or losing control. Between episodes, she worries constantly about having another attack and has begun avoiding crowded places, public transport, and shopping malls. She denies any medical illness, substance use, or recent stressors. Physical examination and baseline investigations are unremarkable. What is the most likely diagnosis?

Explanation

## Diagnosis: Panic Disorder with Agoraphobia ### Clinical Presentation Analysis **Key Point:** The diagnosis rests on three cardinal features: 1. **Recurrent, unexpected panic attacks** — sudden onset of intense fear with autonomic symptoms (palpitations, diaphoresis, trembling, dyspnea, chest discomfort) 2. **Persistent worry about future attacks** — anticipatory anxiety between episodes 3. **Avoidance behavior** — phobic avoidance of situations where escape is difficult (crowds, public transport, malls), meeting criteria for agoraphobia ### Diagnostic Criteria (DSM-5) | Feature | Panic Disorder | Panic Disorder with Agoraphobia | |---------|---|---| | Recurrent panic attacks | ✓ | ✓ | | Anticipatory anxiety | ✓ | ✓ | | Agoraphobic avoidance | ✗ | ✓ | | Functional impairment | Variable | Marked | **High-Yield:** Agoraphobia is not a fear of open spaces per se, but rather a fear of situations from which escape is difficult or embarrassing, or where help is unavailable if panic occurs. This patient's avoidance of crowds and public transport exemplifies this. ### Panic Attack Physiology **Clinical Pearl:** Panic attacks involve a cascade of sympathetic activation: - Hyperventilation → hypocapnia → respiratory alkalosis - Increased cardiac output → palpitations and chest discomfort - Peripheral vasoconstriction → dizziness and paresthesias - Amygdala hyperactivity with impaired prefrontal regulation ### Differential Considerations **Warning:** Do not confuse with: - **Generalized Anxiety Disorder:** Characterized by persistent, diffuse worry over 6+ months without discrete panic attacks or clear situational triggers - **Specific Phobia:** Fear is triggered by a specific object or situation (e.g., heights, animals); attacks are predictable and occur only in the presence of the phobic stimulus - **Acute Stress Disorder:** Occurs within 3 days to 1 month after a defined traumatic stressor; this patient has no trauma history ### Treatment Approach **Mnemonic:** SSRI-CBT-ERP - **S**SSRI (first-line pharmacotherapy: sertraline, paroxetine, escitalopram) - **C**ognitive Behavioral Therapy (restructuring catastrophic thoughts) - **E**xposure and **R**esponse **P**revention (graded in vivo exposure to avoided situations) [cite:DSM-5 Diagnostic and Statistical Manual of Mental Disorders]