F. Assessment of Risk Factors
BACKGROUND
Following a traumatic event, a majority of those exposed may experience posttraumatic mental responses. However, after 9 to 12 months, 15 to 25 percent continue to be disturbed by these symptoms. This group with persistent symptoms may have distinct psychological, social, or biological factors that determine the presence of these ongoing problems. The search for risk factors that increase vulnerability to chronic PTSD occurred early in the history of the study of this disorder. The study of risk factors has become increasingly popular, emphasizing environmental and demographic factors, personality and psychiatric history, dissociation, cognitive and biological systems, and genetic or familial risk (Yehuda, 1999).
Brewin and colleagues (2000) conducted a meta-analysis of risk factors and found that gender, psychiatric history, history of child abuse, and prior adversity play a role in the development of PTSD. More important factors, however, were the severity of the trauma, ongoing stress, and lack of current social support.
RECOMMENDATION
- All patients should be assessed for risk factors for developing ASD or PTSD. Special attention should be given to post-traumatic factors (i.e., social support and functional incapacity) that may be modified by intervention.
- Because of the high prevalence of psychiatric comorbidities in the PTSD population, assessment for depression and other psychiatric comorbidities is warranted (see also VA/DoD Clinical Practice Guideline for the Management of MDD and Psychotic Disorders).
- Substance use patterns of persons with trauma histories or PTSD should be routinely assessed to identify substance misuse or dependency (alcohol, nicotine, prescribed drugs, and illicit drugs) (see also VA/DoD Clinical Practice Guideline for the Management of Substance Use Disorders).
DISCUSSION
The following characteristics have been shown to be risk factors for the development of PTSD:
Pre-traumatic factors
- Ongoing Life Stress
- Lack of Social Support
- Pre-existing Psychiatric disorder
- Other pre-traumatic factors including: female gender, low socioeconomic status, lower level of education, lower level of intelligence, race (Hispanic, Japanese, other ethnic minority), reported abuse in childhood, report of other previous traumatization, report of other adverse childhood factors, family history of psychiatric disorders, poor training or preparation for the traumatic event
Peri-traumatic or trauma related factors
- Severe Trauma
- Type of trauma (interpersonal traumas such as torture, rape or assault convey high risk of PTSD)
- High perceived threat to life
- Age at trauma (School age youth, 40-60 yo)
- Community (Mass) Trauma
- Other peri-traumatic factors including: history of peri-traumatic dissociation and interpersonal trauma
Post-traumatic factors
- Ongoing Life Stress
- Lack of Social Support
- Bereavement
- Major Loss of Resources
- Other post-traumatic factors including: children at home and female with distressed spouse
Individually, the effect size of all the risk factors was modest, but factors operating during or after the trauma, such as trauma severity, lack of social support, and additional life stress, had somewhat stronger effects than pretrauma factors (Brewin et al., 2000).
Pre-traumatic factors
Prior exposure to traumatic events is a
risk indicator for chronic PTSD (Brewin et al., 2000; Ozer et al., 2003).
In particular, a history of exposure to interpersonal violence, in childhood
or adulthood, substantially increases the risk for chronic PTSD following
exposure to any type of traumatic event (Breslau, 2002a; Brewin et al.,
2000; Ozer et al., 2003). Green et al. (2000) surveyed 1,909 college-aged
women and found that those who had experienced interpersonal trauma, and
those who had experienced multiple traumas, experienced “elevated
symptoms.” Dougall et al. (2000) hypothesized that prior trauma
history sensitizes victims to the new stressor, thus potentiating its
impact. They argued that evaluating trauma history is essential for improving
early intervention efforts.
Epidemiological studies have yielded higher rates of PTSD in women than in men in general populations, and there are also a number of gender differences in clinical presentation after trauma. Seedat & Stein studied a series of patients presenting with physical trauma after interpersonal violence and found that “women were more likely than men to have been previously assaulted, or to have sustained injury by a relative or someone known to them, but less likely to have used substances at the time of the assault or to require emergency surgery” (2000). The authors believe that an understanding of gender differences in PTSD rates may eventually help reveal the underlying cause of this disorder.
Pre-existing psychiatric problems are associated with more adverse response to trauma (Norris et al., 2002). Breslau (2002a), in a review of recent epidemiological studies, found that preexisting psychiatric disorder was one of 3 factors that had a predictable effect on the development of PTSD. Both recent meta analyses of risk or predictive factors for PTSD have identified prior psychiatric history as a risk factor for the development of PTSD (Brewin et al., 2000; Ozer et al., 2003). A family history of psychiatric disorders may also contribute to a person’s vulnerability to PTSD. Brewin and colleagues found that “factors such as psychiatric history, reported childhood abuse, and family psychiatric history … had more uniform predictive effects” than did other risk factors such as gender or age at trauma (2000).
Peri-traumatic factors
Foy et al. (1984) published one of the first formal studies to look at
risk factors for PTSD and reported characteristics of trauma exposure
to be of central importance. Numerous studies have since observed a dose-response
relationship between trauma severity and PTSD. The more severe the trauma,
the more likely the person experiencing it will develop PTSD. Armenian
and his colleagues (2000) found this to be true among disaster victims,
Feehan et al. (2001) found higher PTSD rates among more severely-traumatized
members of a general cohort, and in a meta-analysis, Brewin et al., (2000)
found that “factors operating during or after the trauma, such as
trauma severity, lack of social support, and additional life stress, had
somewhat stronger effects than pretrauma factors.” Situations where
the trauma is potentially life-threatening also carry a high risk of PTSD:
in a meta-analysis of 68 PTSD studies, Ozer et al., (2003) found “perceived
life threat” to have a high risk value, and in Woods’ study
of abused women (2000), the perceived threat of homicide played a role
in later development of PTSD. Ozer et al., (2003) also found that dissociation
at the time of the trauma is predictive of later development of PTSD.
Demographic factors may also be predictive. Finnsdottir & Elklit (2002)
found higher rates of PTSD among disaster victims who were young at the
time of the trauma, and in a general group of psychiatric patients Neria
et al. (2002) found young age at trauma to be a risk factor for PTSD.
Finally, biological factors may also be relevant to predicting PTSD. Shalev
et al. (1998) measured the heart rate and blood pressure of eighty-six
trauma survivors at the time of their presentation at a hospital emergency
room, and concluded that “Elevated heart rate shortly after trauma
is associated with the later development of PTSD.” In a meta-analysis,
Yehuda et al. (1998a) reported that studies “demonstrated increased
heart rate and lower cortisol levels at the time of the traumatic event
in those who have PTSD at a follow-up time compared to those who do not.”
Post-traumatic factors
The experience of trauma may have life-altering consequences in terms
of social status, employment, and health, and continuing difficulties
in these areas may contribute to the likelihood that a person will develop
PTSD. Feehan et al. (2001), in interviews with 374 trauma survivors, found
unemployment to be a risk factor. Likewise, in the meta-analysis performed
by Norris et al. (2002), “resource loss” was cited as a risk
for PTSD. Impaired social support is a not-infrequent outcome of a trauma
experience. Armenian et al. (2000), Brewin et al. (2000), Gregurek et
al. (2001), and Ozer et al. (2003) all reported that the loss of support
from significant others can pose a risk for development of PTSD. And finally,
general ongoing life stress may also play a role. Brewin et al. (2000)
reported “life stress” to be more predictive of PTSD development
than are pre-traumatic factors such as gender or age at trauma. Norris
et al. (2002) found that in disaster victims, “secondary stressors”
increased the likelihood of adverse outcomes.
| Evidence | Sources of Evidence | QE | Overall Quality | R | |
|---|---|---|---|---|---|
| Pre-trauma | |||||
| 1 | Prior exposure to traumatic events | Breslau et al., 1999a Brewin et al., 2000 Dougall et al., 2000 Green et al., 2000 Maes et al., 2001 Neria et al., 2002 Ozer et al., 2003 Seedat & Stein, 2000 Zatzick et al., 2002 |
II I II II II II I II II |
Good | B |
| 2 | Female gender | Breslau, 2002b Breslau et al., 1999b Brewin et al., 2000 Finnsdottir & Elklit, 2002 Neria et al., 2002 Seedat & Stein, 2000 Stretch et al., 1998 Zatzick et al., 2002 |
II II I II II II II II |
Good | B |
| 3 | Psychiatric disorders or personality dimensions | Breslau, 2002a Brewin et al., 2000 Maes et al., 2001 Norris et al., 2002 Ozer et al., 2003 |
III I II III I |
Good | B |
| 4 | Cognitive factors: Lower intelligence Neurological soft signs |
Brewin et al., 2000 Gurvits et al., 2000 |
I II |
Good | B |
| 5 | Parental or family history of PTSD | Yehuda et al., 1998b | II | Poor | I |
| 6 | Childhood abuse/assault | Breslau et al., 1999a Breslau, 2002a Brewin et al, 2000 Neria et al., 2002 |
II III I II |
Good | B |
| 7 | Low educational level or socioeconomic status | Armenian et al., 2000 Brewin et al., 2000 Bromet et al., 2002 Finnsdottir & Elklit, 2002 |
II I II I |
Good | B |
| Peri-trauma | |||||
| 8 | Severity of trauma Perceived life threat |
Armenian et al., 2000 Brewin et al., 2000 Feehan et al., 2001 Ozer et al., 2003 Woods, 2000 |
II I II I II |
Good | B |
| 9 | Peri-traumatic dissociation. | Ozer et al., 2003 | I | Good | B |
| 10 | Youth at time of exposure | Brewin et al., 2000 Finnsdottir & Elklit, 2002 Neria et al., 2002 Norris et al., 2002 |
I II II III |
Good | B |
| 11 | Biological factors such as HR increase | Shalev et al., 1998 Yehuda et al., 1998a |
II II |
Fair | C |
| Post-trauma | |||||
| 12 | Resource loss/unemployment | Feehan et al., 2001 Norris et al., 2002 |
II III |
B | |
| 13 | Impaired social support system | Armenian et al., 2000 Brewin et al., 2000 Gregurek et al., 2001 Ozer et al., 2003 |
II I II I |
Good | B |
| 14 | Health problems. | Norris et al., 2002 | III | Poor | I |
| 15 | On-going life stress | Brewin et al., 2000 Norris et al., 2002 |
I III |
Good | A |
| Author | Number | Population | Risk Associated With | Method | QE |
|---|---|---|---|---|---|
| Armenian 2000 | 154 | Disaster victims | Severity of trauma Lack of education Lack of social support |
Interview | II |
| Breslau 1999a | 2181 | General | Previous exposure Multiple exposures Childhood assault |
Phone survey | II |
| Breslau 1999b | 2181 | General | Female | Phone survey | II |
| Breslau 2002a | N/A | N/A | Psychiatric disorder Family history of disorder Childhood trauma |
Lit review | III |
| Breslau 2002b | 2181 | General | Female | Phone survey | II |
| Brewin 2000 | 90,000 | N/A | Lack of social support Life stress Trauma severity Adverse childhood Low intelligence Childhood abuse Low socio-econ. status Family psych history Female Previous trauma Psychiatric history Lack of education Young age Minority race |
Meta analysis | II |
| Bromet 2002 | 600 | Disaster victims | Disadvantaged | Interview | II |
| Dougall 2000 | 108 | Crash site workers | Multiple exposure | Survey/interview | II |
| Fauerbach 2000 | 70 | Burn survivors | Neuroticism | Interview | II |
| Feehan 2001 | 374 | General | Trauma severity (M ) Relation to assailant (F) Unemployment |
Interview | II |
| Finnsdottir & Elklit 2002 | 104 | Disaster victims | Loss of family member Female Young age Lack of education |
Questionnaire | II |
| Green 2000 | 1909 | Sophomore women | Multiple exposure | Questionnaire | II |
| Gregurek 2001 | 42 | Croatian vets | Lack of social support | Questionnaire | II |
| Gurvits 2000 | 21 F 38 M |
Sex abuse Combat vets |
Neurologic soft signs | Exam and tests | II |
| King 1999 | 432 F 1200 M |
Veterans | War-related stressors Post-trauma variables |
Questionnaire? | II |
| Maes 2001 | 127 | Disaster victims | Previous trauma History of phobia Loss of control Alcohol intoxication (decrease the odds) |
Interview | II |
| Neria 2002 | 426 | Psychiatric patients | Female Young age Previous trauma Childhood abuse |
Interview | II |
| Norris 2002 | 60,000 | Disaster victims | Psychological problems Distress (nonspecific) Health problems Life stress Resource loss Youth |
Empirical review | III |
| Ozer 2003 | 68 studies | N/A | Peritraumatic dissociation Perceived life threat Post trauma social support Peritraumatic emotional responses Family psych history Previous trauma Prior psych adjustment |
Meta analysis | I |
| Seedat & Stein 2000 | N/A | Physical trauma, post violence | Female Multiple exposure |
Interview / assess | II |
| Shalev 1998 | 86 | Trauma victims ED | Heart rate elevation | PE | II |
| Stretch 1998 | 1000 | Active duty | Female | Questionnaire | II |
| True 1993 | 4042 twin pair | Viet vets | Genetic influence | Self-report | II |
| Woods 2000 | 160 | Abused women | Trauma severity Risk of homicide |
Interview / assess | II |
| Yehuda 1998a | N/A | ED patients | Increased heart rate Low cortisol levels |
Physical assessment | II |
| Yehuda 1998b | 22 22 |
Holocaust survivors Offspring |
Parental PTSD | Interview / assess | II |
| Yehuda 1999 | N/A | Holocaust offspring | Parental PTSD | Lit review | III |
| Yehuda 2000 | 35 15 |
Holocaust offspring controls |
Low cortisol levels | Urinary cortisol | II |
| Zatzick 2002 | 101 | Trauma victims | Previous trauma Female Intoxication |
Interview | II |
A PubMed clinical query was used to supplement the findings of two recent meta analyses (Brewin et al., 2000; Ozer et al, 2003). The clinical query for etiology identifies case-control and cohort studies. In addition, a few studies recommended by the workgroup have been included.