Updated

Vietnam War veterans suffering from PTSD may also be at risk for an even more debilitating health condition – heart disease.

In a new study funded by the National Institutes of Health (NIH), male twin Vietnam veterans with PTSD were twice as likely to develop heart disease within a 13-year period, compared to veterans who did not have PTSD, Medical Daily reported.

"This study provides further evidence that PTSD may affect physical health," said Dr. Gary H. Gibbons, director of the NIH's National  Heart, Lung, and Blood Institute.

Researchers analyzed the health of 340 identical twins and 222 fraternal twins who were listed in the Vietnam Era Twin Registry.  Of the 177 veterans with PTSD, 22.6 percent went on to develop heart disease, compared to only 8.9 percent of the 425 veterans without PTSD.  Furthermore, if one brother had PTSD and the other did not, the risk of heart disease was almost doubled – 22.2 percent of those with PTSD compared to 12.8 percent of those without.

For the study, heart disease was defined as anything that included heart attacks, overnight hospitalizations for heart-related symptoms and any kind of heart procedures. According to Medical Daily, the scientists followed twins, because it helped them to control for other risk factors, such as genes and the environment.

"This study suggests a link between PTSD and cardiovascular health," Dr. Viola Vaccarino, lead researcher and chair of the department of epidemiology at the Rollins School  of Public Health, told Medical Daily. "For example, 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."

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