PTSD Can Hide and Wait

Post traumatic stress disorder onset may be delayed for months or even years

/ Author:  / Reviewed by: Dominique Brooks, M.D Beth Bolt, RPh

(RxWiki News) There are no hard and fast rules about the timing of PTSD, or post-traumatic stress disorder. While some people may experience symptoms right after the trauma, others may have a longer delay.

In a recent study, researchers followed a group of people who had been injured in serious accidents.

The results of this study showed that PTSD symptoms presented for different patients at different times, from as early as their hospital discharge to as late as 24 months after discharge.

"Seek help if you're experiencing symptoms of PTSD."

Richard A. Bryant, PhD, professor in the School of Psychology at the University of New South Wales in Australia, led an investigation into possible explanations for delayed-onset PTSD after a traumatic event.

PTSD is a mental health condition that can happen after experiencing a traumatic event in which a person has been injured or nearly injured.

Symptoms of PTSD include flashbacks, bad dreams, avoidance of places and people, feeling on edge, having angry outbursts and/or trouble sleeping.

According to the study authors, in roughly 25 percent of PTSD cases, symptoms don’t present until at least six months after exposure to trauma.

For this study, the researchers recruited 785 patients who had been admitted to one of four Level I trauma centers in Australia between 2004 and 2006.  

The researchers assessed the participants at the time of their hospital discharge and three, 12 and 24 months after injury.

Overall, 58 percent of the PTSD patients and 41 percent of the patients without PTSD had mild traumatic brain injuries (MTBI).

The results of this study showed that at the time of hospital discharge, 613 patients had no symptoms of PTSD, 66 had partial symptoms of PTSD and 26 had full PTSD.

After three months, 575 patients had no symptoms of PTSD, 70 had partial symptoms of PTSD and 60 had full PTSD.

After 12 months, 559 had no symptoms of PTSD, 79 had partial symptoms of PTSD and 67 had full PTSD.

After 24 months, 553 had no symptoms of PTSD, 104 had partial symptoms of PTSD and 48 had full PTSD.

The researchers reported that PTSD was found in 9 percent of patients at three months, 10 percent of patients at 12 months and 7 percent of patients at 24 months.

Of the 26 participants with PTSD at the time of their hospital discharge, only 42 percent had PTSD two years later.

The researchers found that delayed onset of PTSD was reported by 49 percent at 12 months and by 18 percent at 24 months.

Of the patients who met the criteria for PTSD after 24 months, 44 percent had no PTSD at three months, meaning 56 percent had partial or full PTSD at the three-month point.

The severity of symptoms in patients who had PTSD at the start of the study, and still had PTSD after 24 months, depended upon the patients having had a prior psychiatric disorder, serious PTSD symptoms from the beginning and the type of injury they had experienced.

The severity of symptoms in patients who did not have PTSD at the start of the study, but developed PTSD after 12 or 24 months, depended upon initial PTSD symptom severity, MTBI, length of time spent in the hospital and the number of stressful events that occurred in their lives between three and 24 months after the first trauma.

The study authors concluded that PTSD symptoms could have a complex trajectory over time, and that ongoing life stressors might compound the initial stress of the trauma and result in delayed PTSD.

The authors also suggested that MTBI increased the risk of delayed PTSD symptoms, especially in those with no initial PTSD symptoms.

This study was published in June in JAMA Psychiatry.

The National Health and Medical Research Council Program and the Victorian Trauma Foundation provided funding for this study. No conflicts of interest were disclosed.

Review Date: 
June 21, 2013
Last Updated:
August 9, 2013