According to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV), to be diagnosed with post-traumatic stress disorder (PTSD), you have to experience a specific set of symptoms for at least one month following exposure to a traumatic event. But in some cases, people may experience delayed-onset PTSD.
Delayed-onset PTSD is not frequently diagnosed, and there is not a great deal of research on this type. However, its occurrence has been observed and studied in some research and it appears that almost a quarter of PTSD cases may be delayed onset. This research has produced some theories on what delayed-onset PTSD is and why it occurs.
Delayed-onset PTSD describes a situation where a person does not develop a PTSD diagnosis until at least six months after a traumatic event. In some cases, the delayed onset of PTSD can be even longer. For example, some people may not begin to experience symptoms consistent with a PTSD diagnosis until years after the experience of a traumatic event. Delayed-onset PTSD of this type has mostly been observed among the elderly, who may develop PTSD stemming from a traumatic event that occurred when they were much younger.
Why Might Delayed-Onset PTSD Occur?The jury is still out with regard to why delayed-onset PTSD may occur. However, there is a small body of research that sheds some light on this condition. First, it appears that people who may be most at risk are those who are experiencing some symptoms of PTSD, but not enough to meet criteria for a PTSD diagnosis (referred to as subthreshold PTSD) after a traumatic event. The development of delayed-onset PTSD in the absence of any previous PTSD symptoms is very rare, and most cases of delayed-onset PTSD seem to reflect a worsening or re-occurrence of symptoms.
Research also shows that the occurrence of additional life stressors or traumatic events may increase the likelihood that someone would develop a PTSD diagnosis in response to a prior traumatic event. The experience of additional traumatic life events may tax one's ability to cope with a previous traumatic event, increasing the likelihood that existing substhreshold PTSD symptoms become more severe. For example, one study of World War II veterans found that many had a worsening of their PTSD symptoms and/or the development of delayed-onset PTSD much later in life. Almost half the veterans indicated that the worsening of their symptoms was triggered by major life changes, such as losing a job or a family member.
Importance of Addressing PTSD Symptoms EarlyAfter a traumatic event, many people may begin to experience some symptoms of PTSD; for most, these symptoms may naturally lessen over time. However, for some, symptoms may persist. Even though symptoms may not be severe enough to meet criteria for a PTSD diagnosis, they can still interfere with your life. In addition, if they are not adequately addressed, they could increase your risk for delayed-onset PTSD.
Given this, it is very important to take steps early on to cope with your PTSD symptoms. There are a number of healthy coping strategies. Most important, you want to be careful not to rely on coping strategies that are focused on the avoidance or suppression of PTSD symptoms, such as substance use. These strategies may help you initially escape your symptoms, but in the long-run, they only cause your symptoms to persist and generally get worse.
In addition, if you notice that you are continuing to experience symptoms from a traumatic event that happened some time ago, it may be worthwhile to talk to a mental health professional. You don't need a diagnosis of PTSD to benefit from PTSD treatments. Even if you don't meet criteria for PTSD, PTSD-focused therapy may help resolve your symptoms, as well as provide you with some additional support and better coping strategies for future life stressors.
If you are looking for treatment providers in your area, there are a number of helpful websites that can assist you in locating the right therapist for your needs.
Andrews, B., Brewin, C.R., Philpott, R., & Stewart, L. (2007). Delayed-onset posttraumatic stress disorder: A systematic review of the evidence. American Journal of Psychiatry, 164, 1319-1326.
Andrews, B., Brewin, C.R., Stewart, L., Philpott, R., & Hejdenberg, J. (2009). Comparison of immediate-onset and delayed-onset posttraumatic stress disorder in military veterans. Journal of Abnormal Psychology, 118, 767-777.
Averill, P.M., & Beck, J.G. (2000). Posttraumatic stress disorder in older adults: A conceptual review. Journal of Anxiety Disorders, 14, 133-156.
Carty, J., O'Donnell, M.L., & Creamer, M. (2006). Delayed-onset PTSD: A prospective study of injury survivors. Journal of Affective Disorders, 90, 257-261.
Hepp, U., Moergeli H., Buchi S., Bruchhaus-Steinert H., Kraemer B., Sensky T., & Schnyder U. (2008). Post-traumatic stress disorder in serious accidental injury: 3-year follow-up study. British Journal of Psychiatry, 192, 376-383.
Horesh, D., Solomon, Z., Zerach, G., & Ein-Dor, T. (2010). Delayed-onset PTSD among war veterans: The role of life events throughout the life cycle. Social Psychiatry and Psychiatric Epidemiology, 46, 863-870.
Smid, G.E., Mooren, T.T., van der Mast, R.C., Gersons, B.P., & Kleber, R.J. (2009).Delayed posttraumatic stress disorder: systematic review, meta-analysis, and meta-regression analysis of prospective studies. Journal of Clinical Psychiatry, 70, 1572-1582.