By Andrew M. Seaman
NEW YORK (Reuters Health) - People suffering from posttraumatic stress disorder (PTSD) may also be at increased risk of heart attacks and strokes, according to a new study of Vietnam War veterans.
After following nearly 300 pairs of male twins, all Vietnam vets, for more than a decade, researchers found that almost a quarter of the men diagnosed with PTSD also had heart disease, compared to less than a tenth of the men without the combat-related stress disorder.
"As time goes by, it's become more and more clear that PTSD is not just something that impacts psychological health. It has broad repercussions throughout the body," said Dr. Viola Vaccarino from the Emory University School of Public Health in Atlanta, the study's lead author.
Behavioral symptoms of PTSD include reliving the traumatic event in memories or nightmares, avoiding situations that may trigger those memories and feelings of paranoia, fearfulness and guilt, according to the U.S. Department of Veterans Affairs.
The symptoms tend to start shortly after a person experiences a traumatic event, such as combat, terrorist attacks, serious accidents, natural disasters and personal violence or abuse.
Physically, Vaccarino's team notes, PTSD sufferers are known to often have raised levels of stress hormones and other chemicals signaling overactivation in the fight-or-flight pathways of the nervous system.
Previous research, including one study examining U.S. veterans from Iraq and Afghanistan, have found that people diagnosed with PTSD and other stress disorders are more likely to develop heart troubles (see Reuters Health story of August 5, 2009 here:).
Vaccarino said, however, that other studies found conflicting results and some relied on data from interviews and questionnaires, which may provide inaccurate information.
For its study, Vaccarino's group used data from a study of twins who were all Vietnam War veterans born between 1946 and 1956. None of the men in the new analysis had heart disease when the study started, between 1987 and 1992.
The 281 twin pairs were asked to return for follow-up exams and interviews between 2002 and 2010 - about 13 years later - and were tested to see how many of the men had developed heart disease.
Overall, 137 participants had met the diagnostic criteria for PTSD at the start of the study and 69 men developed heart disease by the time of their follow-up exam.
About 23 percent of those with PTSD had heart disease, compared to about 9 percent of those without the stress disorder.
The results translated to those with PTSD at the outset being twice as likely as men without the disorder to develop heart disease by the end of the study.
That difference remained even after the researchers accounted for the higher rates of smoking, drinking and high blood pressure among the PTSD sufferers, which could also contribute to heart risks.
Vaccarino told Reuters Health that she and her colleagues were able to confirm their findings by imaging the participants' hearts and showing reduced blood flow in the men with PTSD.
While their study cannot prove that PTSD caused heart disease in the men, she said, people should know the two conditions share an association.
"This study and the other studies provide pretty good evidence that there's an association here and it's likely to be causal, but we don't have the proof," said Dr. Stephen Sidney, director for research clinics at the Kaiser Permanente Northern California Division of Research in Oakland.
"There is enough of an association that physicians should be aware of it," said Sidney, who wrote an editorial accompanying the new study in the Journal of the American College of Cardiology.
Vaccarino said more research is needed to find out exactly how the two conditions are related, but "in the meantime, we need to act on those things that are protective against heart disease in general."
"Patients with PTSD need to realize that they need to take care of their heart, because they are at a higher risk," she said.
SOURCE: http://bit.ly/11AIhhY Journal of the American College of Cardiology, online June 2013.