Post-Traumatic Stress Disorder

Introduction

Post-traumatic stress disorder (PTSD) develops after exposure to an extremely threatening or horrific event or series of events, and is characterised by three symptom clusters: re-experiencing the trauma in the present, deliberate avoidance of reminders, and a persistent sense of heightened current threat.¹

Qualifying events include direct experience of, witnessing, or (for close family or colleagues in relevant occupations) repeated exposure to the details of actual or threatened death, serious injury or sexual violence - combat, serious accidents, physical or sexual assault, natural disasters, torture, and traumatic childbirth are all recognised triggers. Only a minority of people exposed to trauma go on to develop PTSD; most recover naturally over time.

Lifetime prevalence in the UK is around 4-5%. It is more likely after interpersonal trauma (assault, abuse) than after accidents or natural disasters, and after trauma experienced as prolonged, repeated, or inescapable rather than a single discrete event.

Aetiology

PTSD is understood as a failure of normal emotional processing of the traumatic memory, with both neurobiological and psychological contributions.

• Fear conditioning: the trauma becomes strongly associated with sensory and contextual cues, which then trigger a fear response on re-exposure to reminders
• Failure of memory consolidation: traumatic memories are thought to be poorly integrated into normal autobiographical memory, remaining fragmented, sensory and easily triggered rather than being processed as a coherent past event - explaining why flashbacks feel like the trauma is recurring now rather than being recalled
• HPA axis and amygdala: heightened amygdala reactivity and altered cortisol regulation are consistently found, along with reduced hippocampal volume in chronic cases
• Cognitive theory (Ehlers and Clark): persistent PTSD is maintained by appraisals that create a sense of ongoing current threat (for example 'I will never be safe again', 'I am permanently damaged'), together with avoidance and safety behaviours that prevent the trauma memory being updated with more benign information
• Peritraumatic factors: the intensity of fear, horror or helplessness experienced at the time, dissociation during the event, and lack of control all increase risk
• Post-trauma factors: lack of social support, ongoing life stress, and negative reactions from others (blame, disbelief) after disclosure all worsen outcome

Risk factors

• Severity, duration and repetition of the trauma - prolonged or repeated trauma (childhood abuse, torture, captivity) carries the highest risk
• Interpersonal or intentional trauma (assault, sexual violence) carries higher risk than accidental or natural trauma
• Peritraumatic dissociation or a perceived threat to life
• Pre-existing mental illness or previous trauma exposure
• Lack of social support after the event
• Additional life stress in the aftermath (ongoing legal proceedings, financial loss, bereavement)
• Occupational exposure - emergency services, military personnel, healthcare workers
• Female sex and younger age at the time of trauma

Clinical features

ICD-11 requires exposure to a qualifying traumatic event, followed by all three of the core symptom clusters, causing significant impairment, and persisting for at least several weeks.¹

Re-experiencing

• Flashbacks - vivid, involuntary re-living of the trauma with a sense that it is happening again now, ranging from brief intrusions to complete loss of awareness of current surroundings
• Intrusive memories - unwanted, distressing recollections of the event
• Nightmares with trauma-related content
• Intense psychological distress or physiological reactions (palpitations, sweating) on exposure to reminders of the trauma

Avoidance

• Avoidance of thoughts, memories or feelings associated with the trauma
• Avoidance of external reminders - people, places, conversations, activities, situations

Persistent sense of current threat

• Hypervigilance - a heightened state of watchfulness for danger
• Exaggerated startle response
• Irritability, anger outbursts or reckless behaviour
• Sleep disturbance
• Poor concentration

Additional common features include emotional numbing, anhedonia, negative beliefs about oneself or the world, survivor guilt, and dissociative symptoms (depersonalisation or derealisation).

Timing

Symptoms usually begin within the first month after trauma, but onset can be delayed by months or, less commonly, years. Symptoms in the first 4 weeks are classified separately as an acute stress reaction; the diagnosis of PTSD requires symptoms to persist beyond a month, though many people with an acute stress reaction go on to develop PTSD if symptoms do not resolve.

Mental state examination

Differential diagnosis

• Acute stress reaction: the same symptom pattern within the first 4 weeks of trauma
• Adjustment disorder: emotional response to a stressor that does not meet the trauma threshold or the specific symptom pattern of PTSD
• Depression: frequently comorbid; low mood and anhedonia can dominate the picture, but ask specifically about re-experiencing and hyperarousal
• Generalised anxiety disorder: persistent worry without the trauma-specific re-experiencing and avoidance
• Panic disorder: discrete panic attacks not specifically triggered by trauma reminders
• Psychotic disorder: flashbacks can be mistaken for hallucinations by an inexperienced assessor, but are recognised by the patient as memories of a real event rather than externally imposed perceptions
• Traumatic brain injury: can coexist after the same incident (for example a road traffic collision) and shares some symptoms such as poor concentration and irritability
• Substance use disorder: may develop secondarily as self-medication for intrusive symptoms, or intoxication/withdrawal can mimic hyperarousal
• Borderline pattern personality disorder: shares affective instability, dissociation and self-harm with complex PTSD, and the two are frequently confused - complex PTSD is anchored to identified prolonged trauma and includes core re-experiencing symptoms
• Prolonged grief disorder: where the trauma was a bereavement, persistent longing and preoccupation with the deceased predominate over re-experiencing and hyperarousal

Investigations

PTSD is a clinical diagnosis based on a detailed trauma history and the pattern of symptoms over time.

• Trauma-Screening Questionnaire or similar validated tools can be used for case-finding in at-risk groups³
• PCL-5 (PTSD Checklist for DSM-5) or equivalent structured measures to quantify severity and track treatment response
• Screen for comorbid depression, other anxiety disorders, and alcohol or substance misuse, all of which are common
• Physical assessment for any injury sustained during the trauma, and consider organic contributors (for example head injury) if the presentation is atypical

Taking the history sensitively

The assessment itself can be re-traumatising if handled badly, and a poor first disclosure experience is a well-documented reason people disengage and do not return. A few principles make a substantial difference:

• Establish that a trauma occurred and its broad nature - you do not need the details. A full narrative account is the work of therapy, not of a diagnostic assessment, and pressing for specifics achieves nothing clinically while risking considerable distress.
• Ask permission before moving into the area, and make clear the person can decline any question or stop at any point
• Screen rather than excavate - 'Have you ever experienced something so frightening or distressing that it still affects you now?' is usually sufficient to open the topic
• Focus on current symptoms and function, which is what determines management, rather than on the event
• Allow time to settle before the person leaves, and check they are not leaving in an activated or dissociated state
• Ask about ongoing danger - domestic abuse, exploitation or continuing contact with a perpetrator changes the priority entirely, since safety must come before trauma-focused work

Management

In the first month

For mild symptoms within 4 weeks of trauma, NICE recommends watchful waiting with active follow-up, rather than immediate formal intervention, since many people recover spontaneously.²

Established PTSD

Trauma-focused psychological therapy is first-line for PTSD of any severity, and is offered before medication is considered:

• Trauma-focused CBT - helps the person process the traumatic memory, update unhelpful trauma-related beliefs, and gradually reduce avoidance
• EMDR (Eye Movement Desensitisation and Reprocessing) - the person recalls elements of the trauma while making bilateral eye movements or other bilateral stimulation, thought to facilitate reprocessing of the traumatic memory; particularly used where the trauma did not involve prolonged repeated exposure
• Both are typically delivered over 8-12 sessions once trauma-focused, though complex PTSD often needs a longer, staged approach (stabilisation before trauma-focused work)

Trauma-focused CBT for PTSD contains identifiable components worth being able to name: psychoeducation about the trauma response; imaginal reliving or written narrative exposure, revisiting the memory in a controlled way so that it becomes integrated as a past event; cognitive restructuring of appraisals that maintain a sense of current threat ('it was my fault', 'nowhere is safe'); in-vivo exposure to avoided but objectively safe situations; and stimulus discrimination, learning to distinguish the trauma reminder from the trauma itself.

Complex PTSD and the staged approach

Where trauma has been prolonged, repeated and inescapable, going straight into trauma-focused work can destabilise the person. Treatment is therefore usually delivered in three phases: first stabilisation and safety - establishing physical safety, building emotion-regulation and grounding skills, and addressing substance use; then trauma processing using the therapies above; and finally reintegration, rebuilding relationships, identity and functioning. The first phase can take considerable time and is not a delay to treatment but a necessary part of it.

Medication

Drug treatment is not first-line but is used where a person declines psychological therapy, has not responded to it, or has severe comorbid depression.

• Venlafaxine or an SSRI (sertraline) are the drugs of choice
• Antipsychotics are occasionally used adjunctively in severe cases with significant hyperarousal or psychotic-like features, under specialist guidance
• Benzodiazepines are not recommended - they do not treat the core symptoms and carry a risk of dependence, and may worsen recovery by promoting avoidance
• Prazosin is sometimes used off-licence for severe trauma-related nightmares, on the basis of its alpha-1 antagonism; the evidence is mixed and it is a specialist rather than routine option

Complications

PTSD carries a high rate of psychiatric comorbidity: depression, other anxiety disorders, and substance use disorder (often as an attempt at self-medication of intrusive symptoms and hyperarousal) are all common. Relationship and occupational functioning are frequently badly affected by avoidance, irritability and emotional numbing. Suicidal ideation and self-harm risk are increased, particularly with comorbid depression or complex PTSD following childhood trauma.

Red flags

Prognosis

Most people exposed to trauma do not develop PTSD, and of those who do, many improve within the first few months, particularly with good social support. Established PTSD responds well to trauma-focused CBT or EMDR, with the majority of patients achieving significant symptom reduction.

A less favourable course is associated with prolonged or repeated trauma, delayed access to treatment, ongoing life stress, poor social support, and comorbid substance misuse or personality disorder. Complex PTSD following childhood or prolonged trauma tends to run a more chronic course and typically needs longer treatment, but meaningful improvement remains achievable with appropriate specialist input.