Rates of post-traumatic stress disorder (PTSD) are higher among military personnel who had mental or physical health problems before combat, a recent study has found.
Cynthia LeardMann and colleagues at the Naval Health Research Center in San Diego wanted to see whether there are predisposing factors for PTSD. Most previous studies have used retrospective figures, so the team examined volunteers before military deployment.
They write on the website of the British Medical Journal that, “It has not been temporally established if those with poor mental or physical health status are more vulnerable to developing PTSD.”
But they do refer to one study suggesting that prior trauma and prior psychological adjustment were significant predictors of PTSD. Another study suggests that young adults, aged 20 to 23 years, with high levels of anxiety or depression in first grade were one and a half times more likely to develop PTSD after a traumatic event than those with low levels of anxiety and depression in first grade.
In their recent study, LeardMann and her team measured “functional health status” before and after combat exposure among 5,410 U.S. military personnel. The individuals completed medical and psychological questionnaires in 2001 to 2003 before the start of the wars in Afghanistan and Iraq, and again in 2004 to 2006. The questionnaires included the PTSD checklist-civilian version (PCL-C), a 17-item self-report measure of PTSD symptoms.
New-onset PTSD was determined by either meeting the standard DSM-IV criteria or receiving a doctor’s diagnosis. Of the participants who were deployed and reported combat exposure, 395 (7.3 percent) developed PTSD.
Those who were rated in the lowest 15th percent for mental or physical health at baseline “had two to three times the risk of symptoms or a diagnosis of PTSD” at the time of followup compared with the other participants.
Of the new PTSD cases, over half (58 percent) arose in participants with health scores in the lowest 15th percent. These individuals were more likely to be younger, less educated, not married, female, current smokers, or problem drinkers.
The researchers write, “The U.S. military often operates in a highly dynamic, lethal, and technological environment, making it important for service members to be mentally and physically fit.
“In a combat environment, a large volume of visual, auditory, and other information must be interpreted and acted on without hesitation, which requires excellent cognitive abilities, an ability to manage extreme stress, think clearly under pressure, multi-task, and remain vigilant for extended times during prolonged periods of high operational tempo.”
Potential candidates hoping to join the U.S. military are screened physically and mentally,” they explain, and are disqualified if they have any of a number of medical conditions or chronic psychological disorders, including PTSD.
“The largest risk factor for developing new-onset PTSD in this study was low mental health scores at baseline before deployment,” they state. “Individuals with diminished mental health before a traumatic experience might be more likely to react poorly to the event, including having a negative response and dissociative experience.”
They say this is the first study to “prospectively investigate diminished physical and mental health in relation to new onset symptoms or diagnosis of PTSD.” PTSD has previously been linked to suicidal thoughts.
“Concern is growing among the public and veterans that post-deployment health consequences among U.S. military personnel may be considerable and lasting,” they warn.
“A recent report suggested that U.S. marine and army infantry units returning from duty in Iraq and Afghanistan have higher than expected proportions of mental disorders and that as many as ten percent of personnel are returning home with symptoms of post-traumatic stress disorder.
“Combat duty in Iraq has been associated with high use of mental health services and attrition from military service and possible alterations in neural functioning after deployment.”
The findings of this new study imply that it may be possible to identify vulnerable military personnel, as well as members of the public, and target them with interventions to prevent new-onset post-traumatic stress disorder. These interventions could include early help after exposure to stress, or protection from stressful exposures when possible.
The team adds that further research is needed to better understand resilience against PTSD and vulnerability to it. Other research should aim to develop better screening and diagnostic approaches, treatment strategies, and the benefits of increased awareness and improved care provision.
LeardMann, C. A. et al. Baseline self reported functional health and vulnerability to post-traumatic stress disorder after combat deployment: prospective U.S. military cohort study. The British Medical Journal, 2009;338:b1273.
Ozer, E. J. et al. Predictors of post-traumatic stress disorder and symptoms in adults: a meta-analysis. Psychological Bulletin, Vol. 129, January 2003, pp. 52-73.
Storr, C. L. et al. Childhood antecedents of exposure to traumatic events and post-traumatic stress disorder. The American Journal of Psychiatry, Vol.164, January 2007, pp. 119-25.
Smith, T. C. et al. New onset and persistent symptoms of post-traumatic stress disorder self reported after deployment and combat exposures: prospective population based U.S. military cohort study. The British Medical Journal, 2008;336:366-371.