Post-traumatic stress disorder may take a toll on the hearts of military service members.
Researchers studying veterans of the Vietnam War discovered service members who had been diagnosed with PTSD faced double the risk of developing heart disease than soldiers without the mental health condition.
The research provides the first long-term look at the association between PTSD and heart disease using computerized imaging techniques.
"This study provides further evidence that PTSD may affect physical health," Dr. Gary H. Gibbons, director of the NIH's National Heart, Lung, and Blood Institute, which partially funded the study, said in a statement. "Future research to clarify the mechanisms underlying the link between PTSD and heart disease in Vietnam veterans and other groups will help to guide the development of effective prevention and treatment strategies for people with these serious conditions."
PTSD is an anxiety disorder that can cause a person to experience flashbacks, bad dreams and frightening thoughts when they're not in real danger, according to the National Institute of Mental Health. PTSD can cause sufferers to avoid places or events that remind them of their trauma. PTSD can cause people to feel easily startled or always on edge, and can also bring about strong feelings of guilt, depression and worry.
About 5.2 million adults have PTSD during a given year, according to the U.S. Department of Veterans Affairs. PSTD has been diagnosed in approximately 11 to 20 percent of veterans of the Iraq and Afghanistan wars, in as many of 10 percent of Gulf War Veterans about 30 percent of Vietnam Veterans, according to the VA department.
For the study, researchers recruited 562 middle-aged sets of twins who were part of a Vietnam era registry. Twin studies allow researchers to rule out some genetic and environmental factors that skew the results.
They found about 23 percent of twins who had been diagnosed with PTSD had heart disease, compared to nearly 9 percent of twins who didn't have PTSD. Heart ailments included heart attacks, hospitalizations for heart-related symptoms, or undergoing a heart procedure.
Nuclear imaging scans of the individuals' hearts showed that those with PTSD almost had twice as much reduction in blood flow to the heart as those without PTSD. Lack of blood flow to the heart could lead to heart attacks, stroke and cardiac arrest.
The researchers also looked at a set of 234 twins where one brother had PTSD and the other did not, and found the incidence of heart disease was almost double in those with PTSD (22 percent) compared to those without (almost 13 percent).
The study did not prove cause and effect, but lent evidence to a link between PTSD and heart health for military members.
"Repeated emotional triggers during everyday life in persons with PTSD could affect the heart by causing frequent increases in blood pressure, heart rate, and heartbeat rhythm abnormalities that in susceptible individuals could lead to a heart attack," Dr. Viola Vaccarino, chair of the department of epidemiology at the Rollins School of Public Health at Emory University in Atlanta, said in a press release.
The study was published June 25 in the Journal of the American College of Cardiology.