A line of veterans in uniform faces away from the camera.Posttraumatic stress (PTSD) is a common reaction to traumatic or stressful events. Studies indicate 3.5% of the United States (U.S.) population will experience PTSD in any given year. Almost 37% of these cases can be classified as “severe.”

Someone with PTSD may relive a traumatic experience through memories and dreams. They may avoid reminders of the trauma to prevent emotional distress. PTSD can also involve memory issues and a heightened reactivity to one’s surroundings.

PTSD takes many forms. It may happen due to a natural disaster or a personal tragedy. It may arise immediately after an experience or years later. People of any gender, ethnicity, and background can experience it. 

Posttraumatic stress is a treatable condition. People with PTSD may wish to contact a therapist. Therapy can help people process distressing emotions and memories. Understanding one’s symptoms is often the first step to reducing them.

What Causes PTSD?

PTSD can occur after any type of physically or psychologically stressful event. Situations that may bring about PTSD include:

  • Transportation accidents
  • Military combat
  • Domestic violence
  • Sexual abuse or assault 
  • Vicarious trauma, such as learning of the death of a loved one or experiencing an attack as a bystander

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During a shocking or scary event, it is natural to experience a “fight or flight” response. Increased adrenaline and stress can be necessary for survival in emergencies. Strong emotions like anger and fear are also common.

Yet some people will continue responding to trauma long after the danger has passed. Their mind’s immediate reaction to the emergency becomes a default pattern. Mental health professionals look for behaviors that have a lasting and detrimental impact. When someone’s response to trauma interferes with their daily life, a diagnosis of PTSD may be appropriate. 

Symptoms of PTSD

The Diagnostic and Statistical Manual (DSM) outlines four categories of PTSD symptoms: re-experiencing, avoidance, arousal/reactivity, and cognition/mood. To qualify for a PTSD diagnosis, an individual should have symptoms from each category. All the symptoms must have been present for at least one month.

1. Re-experiencing symptoms (need at least one):

  • Recurring and intrusive memories of the trauma
  • Flashbacks where the person feels or acts as if the trauma is recurring
  • Disturbing or scary thoughts when faced with reminders of trauma
  • Nightmares
  • Intense physiological reactions to reminders of trauma, such as rapid heartbeat and sweating

2. Avoidance symptoms (need at least one):

  • Avoiding reminders of the traumatic experience, including people, situations, places, or objects
  • Repressing or ignoring emotions or thoughts related to the event

3. Arousal and reactivity symptoms (need at least two):

  • Outbursts of anger with little provocation
  • Reckless or self-destructive behavior
  • Startling easily
  • Tension or a feeling of being “on edge”
  • Insomnia
  • Difficulty concentrating

4. Cognition or mood symptoms (need at least two):

  • Inability to remember an important detail of the event
  • Exaggerated negative beliefs such as “I am bad” or “nobody can be trusted”
  • Feeling constant negative emotions like shame or horror
  • Unfairly blaming oneself or others for the event  
  • Inability to feel positive emotions like happiness and satisfaction
  • Lack of passion for previously enjoyed activities
  • Feeling detached from other people

Most cases of PTSD begin within the first three months after the trauma, but some individuals may not develop symptoms until six months or later.

History of PTSD 

Before modern medicine, doctors thought posttraumatic stress was a physical condition. American Civil War records speak of a condition called “Da Costa’s Syndrome.” Soldiers diagnosed with the syndrome would have anxiety, a rapid pulse, and trouble breathing. Medics assumed the soldiers had overstimulated their hearts. Soldiers received medicine to control their symptoms and returned to war soon after.

In World War I, posttraumatic stress was called “shell shock.” Common symptoms of shell shock included headaches, flashbacks, and sensitivity to loud noises. Physicians thought soldiers’ symptoms were due to brain damage from artillery shells. But many soldiers who hadn’t been near explosions showed shell shock as well. Scientists dismissed this second group as having “a weakness of nerves.” 

Modern research shows no connection between PTSD and resilience. There is no evidence that individuals with PTSD are emotionally weaker than anyone else. But in the early twentieth century, soldiers with posttraumatic stress often faced extreme stigma. During WWI and WWII, the military’s priority was usually returning soldiers to the battlefield rather than promoting mental health.

The DSM did not list posttraumatic stress as a diagnosis until 1980. By then, scientists had data from Vietnam veterans, Holocaust survivors, and more. Experts agreed PTSD was a mental health condition rather than a physical injury or character flaw. 

PTSD in Modern Veterans

Due to the nature of modern warfare, veterans from Iraq and Afghanistan are especially likely to face trauma. The U.S. Department estimates 10-18% of veterans develop PTSD after they return. A soldier’s risk of PTSD depends on their demographics and their experiences in combat.

A distressed woman looks out the windowSoldiers who are unmarried and have lower levels of education are more likely to have PTSD. Female service members also have higher risks of PTSD. According to a 2015 study, 5% of female soldiers reported sexual assault. In the military, women are five times more likely to experience sexual assault than men.

Soldiers who face more combat stressors are more likely to develop PTSD. Combat stressors include seeing corpses, having a comrade killed, being ambushed, and getting injured in battle. Soldiers with longer deployment periods also had higher rates of posttraumatic stress.

PTSD and Gender

In America, women are more than twice as likely as men to develop PTSD. An estimated 9.7% of women will experience PTSD in their lifetimes, compared to 3.6 % of men. The difference may be partly due to how women experience higher rates of sexual assault and domestic violence. Rape is one of the traumas most likely to lead to posttraumatic stress (Others include military combat, politically-motivated internment, and genocide.).

PTSD in Racial and Ethnic Minorities

Some racial and ethnic minorities have higher rates of posttraumatic stress. A 2011 study of the general U.S. population found the highest rate of PTSD among black residents (8.7%). White individuals had a lifetime prevalence of 7.4%, and Hispanic residents had a rate of 7.0%. Asians had the lowest rates of PTSD (4.0%). 

Certain minority subgroups also have higher PTSD rates. Some estimates suggest about half of Holocaust survivors have posttraumatic stress.

However, ethnic and racial prevalence rates vary between studies. How a study defines PTSD or which people it includes in a minority group can affect data. Several studies have found higher rates of PTSD among Hispanic Americans than either black or white Americans. 

A PTSD diagnosis requires a person to have experienced trauma. Differences in trauma exposure may play a large role in racial and ethnic PTSD rates. Racial and ethnic minorities often face different traumas from other groups. These traumas may include:

  • Racism and discrimination: Prejudice can cause distress and negative life outcomes. For instance, hiring discrimination can lead to unemployment. 
  • Exposure to violence: Minorities may be exposed to wars, ethnic and racialized violence, and crime. Violence by military or law enforcement officers can also be a risk.

A study published in 2010 argues current PTSD measures may fail to account for the traumas of racism and ethnoviolence. Vicarious trauma, such as watching police violence on TV, may act as a catalyst for PTSD. Although the person watching TV is not in direct danger, they may be reminded of historical threats to their identity group. Since hate crimes are often directed toward a group, a person may feel targeted.  

Research suggests PTSD may be under-diagnosed in some minority groups. A 2011 study surveyed African-Americans with a trauma history. Roughly half of participants did not discuss their history or symptoms with a health care provider. When people did share their symptoms, they were less likely to be diagnosed with PTSD. Other studies support the idea that racial and ethnic minorities are less likely to get treatment for posttraumatic stress.

Cross-Cultural Comparison of PTSD Rates 

Measuring cross-cultural PTSD rates can be difficult. Most PTSD research has focused on people living in Western nations. Even when researchers assess PTSD rates in non-Western nations, cultural differences can make it hard to compare results. But the research available so far suggests PTSD rates do vary across cultures.

A 2014 study compared PTSD rates between people living in various European nations. The study found the highest rate (6.67%) among Croatians. Cultural values were a greater predictor of PTSD rates than trauma exposure. Sensation-seeking was strongly linked to PTSD rates.

A person’s risk of trauma exposure depends on many cultural factors, including:

  • Where they live
  • Their social class within that culture
  • How much community support they have
  • Political conflict

High exposure to violence often correlates to a high rate of PTSD. Refugees are more likely than non-refugees to develop PTSD. The World Health Organization estimates 1% of non-refugees have the condition. By comparison, many studies have placed the prevalence rate among refugees at 15%. The largest research review to date included refugees from 40 different nations. This review estimates 30% of refugees have PTSD.

PTSD in Children

Children can develop posttraumatic stress in a similar manner to adults. However, there are a few symptoms unique to children. 

A father puts his hand around his insecure son's shoulders.Children 12 and younger typically do not have flashbacks the way adults do. Yet it is common for children to reenact the trauma through play. For instance, a child who witnessed a school shooting may repeatedly play with pretend guns. Children with PTSD may believe there were warning signs before the traumatic event. They might watch for these signs so they can “predict” the next event. 

Teenagers with PTSD often develop negative beliefs about themselves. They may judge themselves as “damaged” or “cowardly” compared to their peers. They may also show reluctance to try age-appropriate activities like driving or dating. Adolescents with PTSD are more likely to develop aggression and risk-taking behaviors than people of other ages.  

PTSD and Co-Occurring Mental Health Conditions

People with PTSD are 80% more likely to have a comorbid mental health concern than those without the condition. Depression, substance abuse, and anxiety often co-occur with PTSD. Children with PTSD are likely to have comorbid oppositional defiant behavior and separation anxiety. Veterans with PTSD are 48% likely to also have a mild traumatic brain injury.

Other mental health issues can exacerbate PTSD symptoms. They may lower mood, disrupt concentration, or bring out aggressive tendencies. These complicating issues can prevent individuals from seeking help. They may isolate themselves from loved ones or avoid treatment resources. If someone with PTSD has a comorbid condition, it can be quite difficult for them to get necessary care. 

A therapist can identify if co-occurring conditions are contributing to PTSD. Therapy can help someone reduce symptoms from PTSD and any other diagnoses. There is no shame in seeking help


  1. Aging Holocaust survivors still suffer from PTSD. (n.d.). Retrieved from https://www.anxiety.org/holocaust-survivors-trauma-ptsd-yom-hashoah
  2. Alegria, M., Fortuna, L. R., Lin, J. Y., Norris, L. F., Gao, S., Takeuchi, D. T., . . . Valentine, A. (2013). Prevalence, risk, and correlates of posttraumatic stress disorder across ethnic and racial minority groups in the U.S. Medical Care, 51(12), 1114-1123. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3922129
  3. American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing. 
  4. Brady, K. T., Killeen, T. K., Brewerton, T., & Lucerini, S. (2000). Comorbidity of psychiatric disorders and posttraumatic stress disorder. The Journal of Clinical Psychiatry. Retrieved from http://psycnet.apa.org/record/2000-15466-003 
  5. Burri, A., & Maercker, A. (2014). Differences in prevalence rates of PTSD in various European countries explained by war exposure, other trauma and cultural value orientation. BMC Research Notes, 7(1), 407. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4114166
  6. Female service members say they face retribution for reporting sexual assaults. (2015, May 1). McClatchy DC Bureau. Retrieved from http://www.mcclatchydc.com/news/nation-world/national/national-security/article24783976.html
  7. Graves, R. E., Freedy, J. R., Aigbogun, N. U., Lawson, W. B., Mellman, T. A., & Alim, T. N. (2011). PTSD treatment of African American adults in primary care: The gap between current practice and evidence-based treatment guidelines. Journal of the National Medical Association, 103(7), 585-593. Retrieved from https://search.proquest.com/openview/815872143532a70ec6b7a32fa18e39a3/1?pq-origsite=gscholar&cbl=36588
  8. Helms, J. E., Nicolas, G., & Green, C. E. (2010). Racism and ethnoviolence as trauma: Enhancing professional training. Traumatology, 16(4), 53-62. Retrieved from http://psycnet.apa.org/buy/2011-01946-007
  9. Hinton, D. E., & Good, B. J. (2016). Culture and PTSD: Trauma in global and historical perspective. Philadelphia, PA: University of Pennsylvania Press.
  10. History of PTSD in veterans: Civil War to DSM-5. (2017, May 31). U.S. Department of Veterans Affairs. Retrieved from https://www.ptsd.va.gov/public/PTSD-overview/basics/history-of-ptsd-vets.asp
  11. Kessler, R. C., Sonnega, A., Bromet, E., Hughes, M., & Nelson, C. B. (1995). Posttraumatic stress disorder in the National Comorbidity Survey. Archives of General Psychiatry, 52(12), 1048-1060. Retrieved from https://jamanetwork.com/journals/jamapsychiatry/article-abstract/497313
  12. Mental health effects of serving in Afghanistan and Iraq. (2015, August 13). U.S. Department of Veterans Affairs. Retrieved from https://www.ptsd.va.gov/public/PTSD-overview/reintegration/overview-mental-health-effects.asp
  13. Perkonigg, A., Kessler, R. C., Storz, S., & Wittchen, H. U. (2000). Traumatic events and post‐traumatic stress disorder in the community: prevalence, risk factors and comorbidity. Acta Psychiatrica Scandinavica, 101(1), 46-59. Retrieved from http://onlinelibrary.wiley.com/doi/10.1034/j.1600-0447.2000.101001046.x/full 
  14. Pole, N., Best, S. R., Metzler, T., & Marmar, C. R. (2005). Why are Hispanics at greater risk for PTSD? Cultural Diversity and Ethnic Minority Psychology, 11(2), 144-161. Retrieved from http://psycnet.apa.org/buy/2005-04428-004
  15. Post-traumatic stress disorder. (2016). National Institute of Mental Health. Retrieved from https://www.nimh.nih.gov/health/topics/post-traumatic-stress-disorder-ptsd/index.shtml 
  16. PTSD in children and teens. (2015, August 13). U.S. Department of Veterans Affairs. Retrieved from https://www.ptsd.va.gov/public/family/ptsd-children-adolescents.asp
  17. Roberts, A. L., Gilman, S. E., Breslau, J., Breslau, N., & Koenen, K. C. (2011). Race/ethnic differences in exposure to traumatic events, development of post-traumatic stress disorder, and treatment-seeking for post-traumatic stress disorder in the United States. Psychological Medicine, 41(1), 71-83. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3097040/?report=reader#__ffn_sectitle
  18. Silove, D., Ventevogel, P., & Rees, S. (2017). The contemporary refugee crisis: An overview of mental health challenges. World Psychiatry, 16(2), 130-139. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5428192
  19. What is posttraumatic stress disorder? (2013). American Psychiatric Association. Retrieved from https://www.psychiatry.org/patients-families/ptsd/what-is-ptsd  
  20. Women, trauma and PTSD. (2015). National Center for PTSD. Retrieved from http://www.ptsd.va.gov/public/pages/women-trauma-and-ptsd.asp 
  21. World War I: 100 years later. (2010). Smithsonian Magazine. Retrieved from https://www.smithsonianmag.com/history/the-shock-of-war-55376701