Fact Sheet: Post-Traumatic Stress Disorder

Following exposure to a stressful event many people develop symptoms. These can include feeling detached from one’s surroundings, recurrent images or thoughts of the event, exaggerated anxiety, feelings of anger, difficulty sleeping, avoidance of reminders of the trauma, an enhanced startle response and dreams and nightmares.

Usually these symptoms subside in the days or weeks following the traumatic event. However, in some cases they persist. If they persist for longer than one-month after the trauma and they cause significant distress or impairment in functioning then these may be the symptoms of post-traumatic stress disorder (PTSD).

The types of traumatic events that are usually linked with PTSD are extreme stressors that involve actual or threatened death or serious physical injury to oneself or another person. Examples of such events include, military combat, violent assault, accidents, natural disasters, and being diagnosed with a life-threatening illness.

If symptoms have been present for less than 1-month the condition may satisfy criteria for acute stress-disorder. When symptoms last for 1-3 months they may meet criteria for acute PTSD, when they last for longer than 3 months this may be chronic PTSD. In some cases a condition of delayed-onset PTSD occurs. Here at least 6 months have elapsed between the traumatic event and the development of symptoms.

It is important to note that not all symptoms that occur after exposure to a traumatic event should be identified as PTSD. Symptoms such as avoidance, decreased activity, emotional numbing and sleep disturbances may be indicative of depression, and this may be a more appropriate diagnosis that would require a different type of treatment. In some cases there may be both PTSD and depression that may require additional considerations in planning treatment.


Both exposure therapy and cognitive-behaviour therapy have been found to be effective treatments for PTSD. Exposure therapy involves exploring memories of the traumatic event and repeatedly going over them in order to reduce the anxiety they cause. There are a number of different versions of exposure some of which aim to modify aspects of the memory. Cognitive behaviour therapy (CBT) often involves exposure or reliving but also includes (to varying degrees) modifying thoughts and beliefs about the trauma. Research studies have shown that cognitive therapy with or without exposure seem to be more or less equivalent in their effectiveness. One of the limitations with exposure-based treatment is that it can be uncomfortable for the patient.

Metacognitive Therapy (MCT) is the latest development in treatment and our development work and trials show this approach is highly effective. It is usually brief and does not rely on exposure to memories or detailed discussion of the trauma itself. It is based on research identifying the factors that impede normal emotional recovery following trauma. The therapist works with the patient to change their style of reacting to spontaneously occurring memories, thoughts and symptoms. In this way in-built psychological recovery processes are allowed to operate. This treatment approach is recommended and is supported by data from several published studies and studies in preparation.

Drug treatments are not recommended specifically for PTSD, but if other symptoms such as depression are a problem then drug treatment may be considered. However, psychological treatment remains the first choice.

MCT References

Wells A (2008). Metacognitive Therapy for Anxiety and Depression. New York: Guilford Press.

Wells, A & Sembi S (2004). Metacognitive therapy for PTSD: A core treatment manual. Cognitive and Behavioral Practice, 11, 365-377.

Wells A & Sembi S (2004). Metacognitive therapy for PTSD: A preliminary investigation of a new brief treatment. Journal of Behavior Therapy and Experimental Psychiatry, 35, 307-318.

Wells A, Welford M, et al (2008). Treating chronic PTSD with metacognitive therapy: An open trial. Cognitive and Behavioral Practice (in press).