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Posttraumatic Reactions and Diagnoses

The vast majority of individuals exposed to potentially traumatic events experience posttraumatic reactions, such as intrusive memories of the event or autonomic arousal (e.g., difficulty concentrating, hyper-alertness, increased physiological activation and reactivity) within hours or days of the traumatic event. Most reactions remit spontaneously within the first month or so, as the individual processes them and comes to term with what happened (Rothbaum, Foa, Riggs, Murdock, & Walsh, 1992; Nugent, Saunders, Williams, Hanson, Smith, & Fitzgerald, 2009; Orcutt, Erickson, & Wolfe, 2004).

However, in some cases, the reactions persist, and some become clinical symptoms that meet criteria for one or more posttraumatic diagnoses, per the DSM-5 (Marshall, Olfson, Hellman, Blanco, Guardino, & Struening, 2001). In the early aftermath (ranging from two days to a month) post-trauma, these symptoms may meet criteria for Acute Stress Disorder (ASD). If they last more than a month, they may then meet criteria for PTSD.  According to the DSM-5, “The essential feature of PTSD is the development of characteristic symptoms following exposure to one or more traumatic events,” (American Psychiatric Association, 2013; p. 274).

Additionally, “The symptoms of PTSD and the relative predominance of different symptoms may vary over time…. Symptom recurrence and intensification may occur in response to reminders of the original trauma, ongoing life stressors, or newly experienced traumatic events” (American Psychiatric Association, 2013; p. 277).

A delay of months or even years may occur before the full criteria for the diagnosis are met (“delayed expression” PTSD).

Source:  Clinical Practice Guideline for the Treatment of Posttraumatic Stress Disorder (PTSD) in Adults (February 24, 2017), p.7.  https://www.apa.org/ptsd-guideline/ptsd.pdf