Post-traumatic stress disorder (PTSD) may reduce the ability of blood vessels to fully dilate, which may raise the risk of heart attack and stroke, according to a new study of veterans published in the Journal of the American Heart Association.
The findings showed that the blood vessels of veterans with PTSD were less reactive and did not expand normally in response to stimuli compared to veterans without PTSD. Less reactive blood vessels are associated with the development of heart disease and other serious conditions.
“Traditional risk factors such as high blood pressure, diabetes, high cholesterol and smoking, have not fully explained why people with PTSD seem to be at higher heart disease risk. Our study suggests that chronic stress may directly impact the health of the blood vessels,” said lead author Marlene Grenon, M.D., associate professor of surgery at the University of California San Francisco and vascular surgeon at the Veterans Affairs Medical Center San Francisco /Veterans Affairs Medical Center-Surgical Services.
For the study, the researchers used a standard test known as flow-mediated dilation (FMD) to gauge how well an artery in the arm relaxes and expands in response to the squeezing of a blood-pressure cuff.
They compared the FMD scores of 67 veterans (average age 68, 99 percent male) with PTSD and 147 veterans (average age 69, 91 percent male) without PTSD. The presence of PTSD was defined as a score of 40 or higher on the PTSD Symptom Checklist.
The findings showed that veterans with PTSD had significantly lower FMD scores; that is, their blood vessels expanded only 5.8 percent compared to 7.5 percent among non-PTSD veterans, indicating a less-healthy response in the lining of their blood vessels.
Veterans with PTSD were more likely to be male and to have a diagnosis of depression, but less likely to be taking ace-inhibitors or beta-blockers to treat high blood pressure. Aside from PTSD, lower scores on the FMD test were also linked to increasing age, worse renal function, and high blood pressure.
After adjusting for differences in age and the presence of other conditions and treatments, PTSD itself was still very strongly linked to reduced blood vessel dilation.
While the current study only included veterans, PTSD can also occur in non-veterans as a result of experiencing or observing a terrifying event, such as warfare, natural disasters, sexual assault, other physical violence, or trauma.
People with PTSD may experience prolonged anxiety, flashbacks, nightmares and many other severe symptoms. The disorder is estimated to affect 7.7 million people in the United States according to the U.S. Department of Health and Human Services National Institutes of Health.