Battle Continues Over Vietnam PTSD Numbers
Thursday, August 23, 2007; 12:00 AM
THURSDAY, Aug. 23 (HealthDay News) -- Decades after the last U.S. troops departed Vietnam, the debate still rages on how many veterans of that conflict suffered or still suffer from post-traumatic stress disorder.
Post-traumatic stress disorder (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 years following the end of U.S. involvement in Vietnam, the actual number of veterans psychologically scarred by what they had encountered in the war became the subject of heated controversy.
A 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 lifetime figure of 30.9 percent and a current figure of 15.2 percent. Both studies relied heavily on veterans' self-reports of PTSD symptoms and exposure to wartime trauma, and both drew heavy criticism.
Last August, a paper published in the prestigious journalSciencedowngraded the estimated percentage of Vietnam veterans suffering from PTSD to an 18.7 percent lifetime prevalence rate and 9.2 percent current rate. The variance, the authors stated, was due to differences in how they defined PTSD.
But perhaps more important, according to the authors, theSciencepaper confirmed a strong "dose/response relationship" between the severity of exposure to war-related stressors and PTSD. And they did not find any evidence for exaggeration in veterans' reports, a claim which had been made by some critics of the original estimates.
That paper, which relied on what the authors called a "treasure trove" of historical material not available when the NVVRS was conducted, had sought to squelch the previous controversy.
But it didn't. In fact, a new article -- one of four published in the August issue of theJournal of Traumatic Stress-- has pushed the number of estimated Vietnam veterans currently experiencing PTSD downward even further, to just 5.4 percent.
"I thought [this issue] had been settled," said Bruce Dohrenwend, the lead author of theSciencepaper and a Columbia University professor. "I think the facts are pretty clear; the interpretations of the facts are what's different."
The latest round of debate, in theJournal of Traumatic Stress, includes an article by Dohrenwend and colleagues, delineating their methods and findings.
Meanwhile, the author of the newest set of numbers, Richard McNally, a professor of psychology at Harvard University, said he feels that people have misinterpreted his work as an attempt to disparage Dohrenwend.