"Both wars have been described as 'wars without fronts,' where there's great difficulty telling peaceful civilians from enemy combatants," noted lead researcher Bruce Dohrenwend, chief of research at the New York State Psychiatric Institute. "Whether rates of PTSD will be the same, higher or lower in U.S. veterans of the Iraq war will depend on differences, as well as similarities, between the two wars," he added.
The findings appear in the Aug. 18 issue of Science.
PTSD is an anxiety disorder involving nightmares, flashbacks and panic attacks linked to event "triggers" that develop after exposure to combat or other extremely disturbing events.
In the decades following the pullout of U.S. troops from Vietnam, the actual number of veterans psychologically scarred by what they had encountered in the war became the subject of heated debate. One 1988 study, conducted by the U.S. Centers for Disease Control and Prevention, estimated a relatively low lifetime rate of PTSD among veterans of 14.7 percent.
But a second government study -- the National Vietnam Veterans Readjustment Study (NVVRS) -- calculated a much higher figure of 30.9 percent. Both studies relied heavily on veterans' self-reports of PTSD symptoms and exposure to wartime trauma.
The NVVRS results gave rise to the "1-in-3" statistic often cited in the media and elsewhere when describing Vietnam's emotional toll on soldiers.
However, the NVVRS finding did have its skeptics. Many pointed out that only 15 percent of soldiers serving in Vietnam were assigned to actual combat roles.
"So, if you only have 15 percent combat-related troops, how can you have over 30 percent with PTSD?" wondered Dohrenwend, who is also a professor of epidemiology at Columbia University's Mailman School of Public Health, in New York City.
Adding to the controversy was the 1998 publication of B.G. Burkett and Glenna Whitley's Stolen Valor, which detailed the faked histories of thousands of self-styled Vietnam veterans, many of whom had never left the United States.
So, to help verify the data on PTSD, Dohrenwend's group decided to ignore self-reports and concentrate instead on thousands of pages of military records. These records included detailed soldiers' histories and such statistics as month-by-month casualty rates for each division serving in Vietnam.
"We also had a marvelous dataset collected by Vietnam and Korean war veterans," Dohrenwend said. "It took them 12 years to analyze the records data on all 58,000 war-related deaths in Vietnam."
With such a precise background of events to work with, the researchers were able to corroborate most of the PTSD-related claims made by veterans.
The vast majority were exposed to horrific events during the conflict, Dohrenwend concluded. "We actually pushed that very hard," he said. "If that weren't the case, we'd have found it."
The researchers also solved the 30-vs-15 dilemma. "You've got 10 percent infantry and their counterparts from other branches to get that 15 percent combat number," Dohrenwend said. "But there are also the combat support troops -- engineers, medics and the like -- that's another 14 percent right there."
In a "war without fronts" -- where everyone is vulnerable to sudden violence, nearly everywhere -- these support troops are also likely to witness carnage, Dohrenwend said.
Richard McNally, a Harvard professor of psychology and author of an accompanying editorial, agreed. "A good example from the current conflict are individuals who are truck drivers in Iraq -- that's very dangerous duty, but not a combat role per se," he said.
The biggest change in the new study, however, came from a change in the agreed threshold for diagnosing PTSD. In the NVVRS, criteria were set relatively low. However, Dohrenwend's group set the bar at symptoms that caused individuals "functional impairment" in everyday life.
"The symptoms had to produce at least a moderate impairment for a diagnosis of PTSD," McNally said. "And that makes sense, because warfare will change a person -- how could it not? But not all change constitutes a disease or disorder -- there are normal emotional reactions that occur."
This combination of verifiable records and a higher threshold for PTSD diagnosis led Dohrenwend's group to a new figure for lifetime prevalence of PTSD in Vietnam vets of 18.7 percent -- higher than the CDC estimate, but 40 percent lower than the NVVRS sample.
"We've brought a much better methodology to this controversy," Dohrenwend said. "I think we offer a resolution to this question."
The study had some good news for U.S. troops returning from Iraq, as well. The researchers were able to track Vietnam veterans' symptoms over time and found that "the disorders were usually on an improving course," even without treatment, Dohrenwend said.
"About half the cases had remitted ,and even those that were present at follow-up and were highly chronic showed only minor impairment," he added.
That doesn't mean treatment can't help speed up PTSD recovery, however.
"I hope this re-analysis will not lead our government to shortchange the VA, in terms of providing clinical services for returning troops," McNally said. "Let's make sure that people get the help they need soon, so that they don't develop chronic PTSD."
The demand appears to be there: A study released early this year found that a third of U.S. military personnel back from Iraq and Afghanistan are availing themselves of mental health services. And, as was the case nearly 40 years ago in Vietnam, many soldiers who've witnessed scenes of bloodshed and loss in Iraq are showing signs of PTSD.
More information
To learn more about PTSD, head to the U.S. National Institute of Mental Health. |
