Section 6.2: Anxiety, Trauma-Related, and Obsessive-Compulsive Disorders

Why Anxiety, Trauma-Related, and Obsessive-Compulsive Disorders Matter for the PANCE

Anxiety disorders constitute the most common class of psychiatric conditions in the United States, making them highly testable on the PANCE. Clinicians must be expert in differentiating normal anxiety from pathological conditions. PANCE focuses heavily on identifying panic attacks versus Panic Disorder, recognizing the specific diagnostic timelines required by the DSM-5-TR (e.g., 6 months of excessive anxiety for Generalized Anxiety Disorder, 1 month for Post-Traumatic Stress Disorder), understanding the clinical manifestations of Obsessive-Compulsive Disorder (OCD), and selecting first-line pharmacotherapy (SSRIs/SNRIs) and appropriate non-pharmacological interventions like Cognitive Behavioral Therapy (CBT).

Panic Disorder

Pathophysiology and Clinical Presentation

A panic attack is an abrupt surge of intense fear or discomfort that peaks within minutes, during which four or more somatic or cognitive symptoms occur. Panic Disorder is diagnosed when a patient experiences recurrent, unexpected panic attacks, followed by at least 1 month of one or both of the following:

1. Persistent concern or worry about additional panic attacks or their consequences (e.g., losing control, having a heart attack, 'going crazy').
2. A significant maladaptive change in behavior related to the attacks (e.g., avoidance of exercise or unfamiliar situations, which may develop into agoraphobia).

Somatic symptoms of a panic attack include:

• Cardiovascular: Palpitations, pounding heart, accelerated heart rate, chest pain/discomfort.
• Respiratory: Shortness of breath, smothering sensations, choking feeling.
• Neurological: Trembling/shaking, paresthesias (numbness/tingling), dizziness, lightheadedness, syncope.
• Psychological: Derealization (feelings of unreality), depersonalization (being detached from oneself), fear of losing control, and fear of dying.

Diagnostic Workup

Due to the overwhelming somatic symptoms, patients often present to the emergency department convinced they are having a life-threatening medical event (e.g., myocardial infarction). It is mandatory to rule out medical mimics.

• Electrocardiogram (EKG): To rule out arrhythmia, ischemic changes, or prolonged QT.
• Thyroid Function Tests (TSH): To rule out hyperthyroidism, which causes tachycardia and anxiety.
• Urine Drug Screen (UDS): To rule out stimulant use (cocaine, amphetamines) or withdrawal.
• Serum Glucose: To rule out hypoglycemia.
• Pheochromocytoma Screen (when indicated): Elevated urinary catecholamines or plasma metanephrines.

Clinical Management

• Acute Management: Short-acting benzodiazepines (e.g., alprazolam, lorazepam) provide rapid relief of severe symptoms. However, they should be used strictly for acute rescue, not long-term maintenance, due to the high risk of tolerance, physical dependence, and abuse.
• Long-Term Management: First-line pharmacotherapy is SSRIs (e.g., sertraline, paroxetine, escitalopram). SSRIs require 4-6 weeks to achieve therapeutic efficacy, during which a temporary benzodiazepine bridge is sometimes utilized.
• Non-Pharmacologic: Cognitive Behavioral Therapy (CBT) is highly effective and focuses on restructuring catastrophic misinterpretations of physical sensations.

Generalized Anxiety Disorder (GAD)

Definition and Diagnostic Criteria

Generalized Anxiety Disorder is characterized by excessive anxiety and worry about a variety of topics, events, or activities, occurring more days than not for at least 6 months. The anxiety must be difficult to control and associated with three or more of the following physical or cognitive symptoms (only one is required in children):

• Restlessness or feeling keyed up/on edge.
• Being easily fatigued.
• Difficulty concentrating or mind going blank.
• Irritability.
• Muscle tension.
• Sleep disturbance (difficulty falling or staying asleep, or restless, unsatisfying sleep).

Management

• First-line Pharmacotherapy: SSRIs (escitalopram, paroxetine) or SNRIs (venlafaxine).
• Alternative Agents:
  • Buspirone: A selective 5-HT1A receptor partial agonist. It is unique because it does not cause sedation, cognitive impairment, or physical dependence, and it has no abuse potential. However, it takes 2-4 weeks to become effective, making it useless for acute anxiety.
  • Beta-blockers (Propranolol): Excellent for performance anxiety or autonomic symptoms (tremors, palpitations) but does not treat the underlying psychic anxiety.
• Psychotherapy: CBT is the gold-standard non-pharmacologic treatment, focusing on worry-exposure and relaxation techniques.

Post-Traumatic Stress Disorder (PTSD)

Pathophysiology and Clinical Criteria

PTSD develops following exposure to a traumatic event involving actual or threatened death, serious injury, or sexual violence. The diagnosis requires symptoms from four distinct clusters to persist for at least 1 month:

1. Intrusion Symptoms (at least 1): Recurrent, involuntary, and intrusive distressing memories, dreams, flashbacks (dissociative reactions), or intense psychological/physiological distress at exposure to cues.
2. Avoidance (at least 1): Avoiding distressing memories, thoughts, feelings, or external reminders (people, places, conversations) associated with the event.
3. Negative Alterations in Cognition and Mood (at least 2): Inability to remember key aspects of the trauma, persistent negative beliefs about oneself or the world, distorted blame, persistent negative emotional states, anhedonia, and feelings of detachment.
4. Alterations in Arousal and Reactivity (at least 2): Irritable behavior/angry outbursts, reckless/self-destructive behavior, hypervigilance, exaggerated startle response, concentration problems, and sleep disturbance.

PANCE Timeline Trap: If the patient meets all symptomatic criteria but the symptoms have lasted less than 1 month, the correct diagnosis is Acute Stress Disorder (ASD). ASD can only be diagnosed between 3 days and 1 month post-trauma.

Management

• First-line Pharmacotherapy: SSRIs (specifically sertraline and paroxetine are FDA-approved).
• Nightmare Management: Prazosin, an alpha-1 adrenergic receptor antagonist, is highly effective for reducing trauma-related nightmares and sleep disturbances by blocking central noradrenergic hyperactivity.
• Psychotherapy: Trauma-focused psychotherapies, specifically Cognitive Processing Therapy (CPT), Prolonged Exposure (PE), and Eye Movement Desensitization and Reprocessing (EMDR), are first-line.

Obsessive-Compulsive Disorder (OCD)

Definition and Diagnostic Concepts

OCD is characterized by the presence of obsessions, compulsions, or both.

• Obsessions: Repetitive, intrusive, unwanted thoughts, images, or urges that cause significant anxiety or distress. The patient typically attempts to ignore, suppress, or neutralize them.
• Compulsions: Repetitive behaviors (e.g., handwashing, ordering, checking) or mental acts (e.g., counting, repeating words silently) that the individual feels driven to perform in response to an obsession, or according to rules that must be applied rigidly. The goal is to reduce anxiety or prevent a dreaded event, though the behaviors are not realistically connected to the threat.

Unlike Obsessive-Compulsive Personality Disorder (OCPD), which is ego-syntonic (the patient views their traits as desirable and rational), OCD is ego-dystonic (the patient recognizes that their obsessions and compulsions are irrational, intrusive, and cause significant distress).

Management

• Non-Pharmacologic (First-line): CBT utilizing Exposure and Response Prevention (ERP). This therapy exposes the patient to the anxiety-inducing stimulus (e.g., touching a doorknob) and prevents them from performing the compulsion (e.g., washing hands).
• Pharmacotherapy: High-dose SSRIs (e.g., fluoxetine, sertraline, fluvoxamine) are first-line.
• Refractory Cases: Clomipramine, a tricyclic antidepressant (TCA) with high serotonergic selectivity, is highly effective but reserved as second-line due to its significant anticholinergic side effects, antihistaminic properties, and risk of cardiotoxicity in overdose.

Classic PANCE Traps & Clinical Pearls

• The ASD vs. PTSD Timeline: This is a classic question. A patient with nightmares and flashbacks 2 weeks after an accident has Acute Stress Disorder, not PTSD. The timeline must exceed 1 month for PTSD.
• Ego-Dystonic vs. Ego-Syntonic: In OCPD, the patient is a neat freak who wants everyone else to follow their rules (ego-syntonic). In OCD, the patient hates their rituals (e.g., checking locks 50 times) but feels compelled to perform them to relieve crushing anxiety (ego-dystonic).
• Buspirone Delayed Onset: A patient requesting immediate relief for a panic attack should not be started on buspirone monotherapy, as it takes weeks to work. Use benzodiazepines for immediate distress, and SSRIs for long-term control.