post-traumatic stress disorders

DEFINITION (DSM-5-TR): Exposure to actual or threatened death, serious injury, or sexual violence (direct, witnessed, learned about in a close person, or repeated occupational exposure), followed by symptoms lasting >1 month that cause functional impairment. Four symptom clusters: (1) INTRUSION – recurrent distressing memories, nightmares, flashbacks, intense distress or physiologic reactivity to cues; (2) AVOIDANCE – of memories, thoughts, people, places, or situations linked to the trauma; (3) NEGATIVE ALTERATIONS IN COGNITION AND MOOD – dissociative amnesia for key aspects of the event, distorted blame, persistent negative emotions, detachment, anhedonia, inability to feel positive emotions; (4) AROUSAL/REACTIVITY – hypervigilance, exaggerated startle, irritability, poor concentration, sleep disturbance, reckless behavior.

TIMELINE/DIFFERENTIALS (high-yield): Acute stress disorder = same symptoms lasting 3 days to 1 month after trauma. PTSD = >1 month. Adjustment disorder = identifiable stressor that does not meet criteria for a life-threatening trauma, symptoms within 3 months, resolves within 6 months after the stressor ends. Specifier: "with delayed expression" if full criteria are not met until ≥6 months after the event. Also "with dissociative symptoms" (depersonalization, derealization).

PATHOPHYSIOLOGY: Amygdala hyperreactivity (fear conditioning), decreased ventromedial prefrontal cortex activity (impaired extinction/top-down inhibition), and decreased hippocampal volume (impaired contextualization of memory). Noradrenergic hyperactivity (increased sympathetic tone). HPA axis dysregulation with paradoxically LOW baseline cortisol and enhanced negative feedback sensitivity.

EPIDEMIOLOGY/RISK FACTORS: More common in women, and sexual assault carries the highest conditional risk. Other risk factors include prior psychiatric illness, prior trauma/childhood adversity, lack of social support, and severity of trauma. Common comorbidities: major depression, substance use disorders, anxiety disorders, suicidality.

TREATMENT: - First-line: trauma-focused psychotherapy (prolonged exposure, cognitive processing therapy, trauma-focused CBT, EMDR). - Pharmacotherapy: SSRIs (sertraline, paroxetine are FDA-approved) and venlafaxine. - Prazosin (alpha-1 blocker) for trauma-related nightmares (evidence mixed in larger trials; commonly tested). - Avoid benzodiazepines (no benefit, may worsen outcomes and risk dependence). - Propranolol shortly after trauma has not shown reliable prevention. - Psychological debriefing immediately after trauma is NOT recommended.

BOARD PEARLS: Classic vignette: combat veteran or assault/MVC survivor with nightmares, avoidance, startle response, and irritability >1 month after the event. Distinguish from acute stress disorder (duration), adjustment disorder (stressor severity), and panic disorder/GAD (no trauma link). Always screen for suicide risk and substance use. Complex PTSD (ICD-11) includes added disturbances in self-organization, typically after prolonged or repeated trauma such as childhood abuse.