Post-Traumatic Stress Disorder (PTSD)

Definition

Post-traumatic stress disorder (PTSD) can develop after exposure to a potentially traumatic event that is beyond a typical stressor. Events that may lead to PTSD include, but are not limited to, violent personal assaults, natural or human-caused disasters, accidents, combat, and other forms of violence. Exposure to events like these is common. About one half of all U.S. adults will experience at least one traumatic event in their lives, but most do not develop PTSD. People who experience PTSD may have persistent, frightening thoughts and memories of the event(s), experience sleep problems, feel detached or numb, or may be easily startled. In severe forms, PTSD can significantly impair a person's ability to function at work, at home, and socially.

Additional information about PTSD can be found on the NIMH Health Topics page on Post-Traumatic Stress Disorder.

Prevalence of Post-Traumatic Stress Disorder Among Adults

• Based on diagnostic interview data from National Comorbidity Survey Replication (NCS-R), Figure 1 shows past year prevalence of PTSD among U.S. adults aged 18 or older.¹  
  • An estimated 3.6% of U.S. adults had PTSD in the past year.
  • Past year prevalence of PTSD among adults was higher for females (5.2%) than for males (1.8%).
• The lifetime prevalence of PTSD was 6.8%.²

Figure 1

Post-Traumatic Stress Disorder with Impairment Among Adults

• Of adults with PTSD in the past year, degree of impairment ranged from mild to serious, as shown in Figure 2. Impairment was determined by scores on the Sheehan Disability Scale.³
• Impairment was distributed evenly among adults with PTSD. An estimated 36.6% had serious impairment, 33.1% had moderate impairment, and 30.2% had mild impairment

Figure 2

Prevalence of Post-Traumatic Stress Disorder Among Adolescents

• Based on diagnostic interview data from National Comorbidity Survey Adolescent Supplement (NCS-A), Figure 3 shows lifetime prevalence of PTSD among U.S. adolescents aged 13-18.⁴
  • An estimated 5.0% of adolescents had PTSD, and an estimated 1.5% had severe impairment. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria were used to determine impairment.
  • The prevalence of PTSD among adolescents was higher for females (8.0%) than for males (2.3%).

Figure 3

Data Sources

Statistical Methods and Measurement Caveats

National Comorbidity Survey Replication (NCS-R)

Diagnostic Assessment and Population:

• The NCS-R is a nationally representative, face-to-face, household survey conducted between February 2001 and April 2003 with a response rate of 70.9%. DSM-IV mental disorders were assessed using a modified version of the fully structured World Health Organization Composite International Diagnostic Interview (WMH-CIDI), a fully structured lay-administered diagnostic interview that generates both International Classification of Diseases, 10^th Revision, and DSM-IV diagnoses. The DSM-IV criteria were used here. The Sheehan Disability Scale (SDS) assessed disability in work role performance, household maintenance, social life, and intimate relationships on a 0–10 scale. Participants for the main interview totaled 9,282 English-speaking, non-institutionalized, civilian respondents. Post-traumatic stress disorder (PTSD) was assessed in a subsample of 5,692 adults. The NCS-R was led by Harvard University.
• Unlike the DSM-IV criteria used in the NCS-R and NCS-A, the current DSM-5 no longer places PTSD in the anxiety disorder category. It is listed in a new DSM-5 category, Trauma- and Stressor-Related Disorders.

Survey Non-response:

• In 2001-2002, non-response was 29.1% of primary respondents and 19.6% of secondary respondents.
• Reasons for non-response to interviewing include: refusal to participate (7.3% of primary, 6.3% of secondary); respondent was reluctant- too busy but did not refuse (17.7% of primary, 11.6% of secondary); circumstantial, such as intellectual developmental disability or overseas work assignment (2.0% of primary, 1.7% of secondary); and household units that were never contacted (2.0).
• For more information, see PMID: 15297905 .

National Comorbidity Survey Adolescent Supplement (NCS-A)

Diagnostic Assessment and Population:

• The NCS-A was carried out under a cooperative agreement sponsored by NIMH to meet a request from Congress to provide national data on the prevalence and correlates of mental disorders among U.S. youth. The NCS-A was a nationally representative, face-to-face survey of 10,123 adolescents aged 13 to 18 years in the continental United States. The survey was based on a dual-frame design that included 904 adolescent residents of the households that participated in the adult U.S. National Comorbidity Survey Replication and 9,244 adolescent students selected from a nationally representative sample of 320 schools. The survey was fielded between February 2001 and January 2004. DSM-IV mental disorders were assessed using a modified version of the fully structured World Health Organization Composite International Diagnostic Interview.

Survey Non-response:

• The overall adolescent non-response rate was 24.4%. This is made up of non-response rates of 14.1% in the household sample, 18.2% in the un-blinded school sample, and 77.7% in the blinded school sample. Non-response was largely due to refusal (21.3%), which in the household and un-blinded school samples came largely from parents rather than adolescents (72.3% and 81.0%, respectively). The refusals in the blinded school sample, in comparison, came almost entirely (98.1%) from parents failing to return the signed consent postcard.
• For more information, see PMID: 19507169 .