Dorthe Berntsen

By Brenda L. Mooney

AARHUS, DENMARK--Traumatic experiences in childhood, not wartime experiences, may have greater influence on which deployed servicemembers develop post-traumatic stress disorder (PTSD).

That’s according to a new study from a team of Danish and American researchers seeking to understand why some servicemembers develop PTSD, while others don’t. Their study was published this month in the journal Psychological Science.

"Most studies on PTSD in soldiers following service in war zones do not include measures of PTSD symptoms prior to deployment and thus suffer from a baseline problem,” said psychological scientist Dorthe Berntsen of Aarhus University in Denmark. “Only a few studies have examined pre- to post-deployment changes in PTSD symptoms, and most only use a single before-and-after measure."

For the study, researchers administered a battery of tests, including a PTSD inventory and depression screening, to military personnel five weeks before they were scheduled to leave for Afghanistan. A questionnaire also was completed about traumatic life events, including childhood experiences of family violence, physical punishment, and spousal abuse.

Evaluations continued during deployment, with the study subjects reporting on direct experience of war: perceptions of war zone stress, actual life-threatening war experiences, battlefield wounds, and the experience of killing an enemy.

After the troops returned home to Denmark, researchers assessed them a few weeks after their return, two to four months after their return, and then seven to eight months after their return.

Soldiers found to have developed PTSD also were much more likely to have suffered emotional problems and traumatic events prior to deployment, according to the study. The authors suggested that childhood experiences of violence, especially punishment severe enough to cause bruises, cuts, burns, and broken bones, were predictive of the onset of PTSD.

Researchers also found that those with PTSD symptoms were:

• More likely to have witnessed family violence, and to have experienced physical attacks, stalking or death threats by a spouse;

• More likely to have past experiences that they could not, or would not, talk about; and

• Were less educated than the resilient soldiers.

Berntsen said what she and her colleagues found was very different than some widely held assumptions about PTSD.

Most (84%) of the soldiers showed resilience, either having no PTSD symptoms at all or recovering quickly from mild symptoms.

Of the rest, about 4% showed evidence of "new-onset" trajectory, with symptoms starting low and increasing across the five time periods used for measurement. Furthermore, their symptoms did not appear to be related to a specific traumatic event.

One of the most notable findings was that about 13% of the study participants actually improved during deployment, reporting significant symptoms of stress prior to leaving for Afghanistan that reappeared upon their return home.

The authors suggest that military service, even though it sometimes involves combat, offered more social support and life satisfaction than these particular soldiers had at home. When the study subjects returned to civilian life, they lost the mental health benefits of being valued and experiencing camaraderie.

"We were surprised that stressful experiences during childhood seemed to play such a central role in discriminating the resilient versus non-resilient groups," Berntsen said. "These results should make psychologists question prevailing assumptions about PTSD and its development."