The Epidemiology of Trauma in PTSD

PTSD represents a pathological response to a serious trauma. The evolution of the diagnostic criteria for PTSD has included a broadening of the types of trauma exposures felt sufficient to trigger PTSD.  The original criteria included combat, concentration camp confinement, natural disaster, rape or physical assault.  The current DSM-IV criteria for trauma require that "the person experienced, witnessed or was confronted with an event(s) that involved actual or threatened death or serious injury or a threat to the physical integrity of self or others"


Naomi Breslau from the Michigan State summarized the current state of knowledge regarding the epidemiology of trauma and PTSD--much of which she has been a key research leader.  With the expanded trauma trigger definition, it is estimated approximately 40 to 80% of the U.S. population have experienced one of these traumas.  General population surveys of PTSD complement our knowledge of PTSD outside military personnel.


Only a minority of trauma exposures appear to result in PTSD.   Women appear more vulnerable to a PTSD response than men.  Here is the estimated highest risk traumas for women (% of individuals experiencing the trauma who develop PTSD):


Women

• Held captured/tortured (78%)
• Severe physical assault with injury (56%)
• Rape (49%)
• Lesser assault (36%)
• Serious accident (28%)
• Sexual assault other than rape (24%)

Men

• Shot or stabbed (18%)
• Child life threatening illness (18%)
• Sexual assault (16%)
• Sudden, unexpected death of relative or friend (13%)
• Witnessing a killing/serious injury (9%)

In addition to female gender, presence of a prior childhood anxiety disorder appears to increase risk.  Higher IQ (>115) appears to provide some protective effect.


Prevention of PTSD starts with public health efforts to reduce violent crime and the frequency of severe trauma exposure in the population.  Military service related trauma is also a key area for prevention and early intervention.  Secondary prevention efforts include identifying those exposed to serious trauma, assessing for high risk for PTSD following this trauma and early therapy or pharmacologic intervention. 


Photo of male lion in Kenya courtesy of Sarah Yates

Breslau N (2009). The epidemiology of trauma, PTSD, and other posttrauma disorders. Trauma, violence & abuse, 10 (3), 198-210 PMID: 19406860