Some blood pressure medications may reduce the severity of symptoms of post-traumatic stress disorder, a new study suggests.

In the study, participants with PTSD who took drugs called ACE (angiotensin converting enzyme) inhibitors or ARBs (angiotensin receptor blockers) had lower scores on a test of PTSD symptoms, compared with those who did not take the drugs.

“These results are particularly exciting because it's the first time ACE inhibitors and ARBs have been connected to PTSD, and it gives us a new direction to build on,” said study researcher Dr. Kerry Ressler, an associate professor of psychiatry and behavioral sciences at Emory University School of Medicine in Atlanta.

However, the study only found an association, not a cause-effect link. A clinical trial would have to be conducted to see if the drugs improve symptoms of PTSD better than a placebo, the researchers said.

The study was published online May 1 in the Journal of Clinical Psychiatry.

The study included information from more than 5,000 low-income residents in Atlanta with high levels of exposure to violence and physical and sexual abuse, resulting in high rates of PTSD.

About 500 participants in this study were exposed to at least one traumatic event, and 180 (35 percent) met the criteria for diagnosis with PTSD. Twenty-six of the participants with PTSD were also taking ACE inhibitors or ARBs.

People with PTSD can experience three types of symptoms: hyperarousal, avoidance or numbing, and intrusive thoughts. All the participants in the study reported how often they experienced these symptoms, and the responses were compiled into a PTSD symptom score.

Patients taking ACE inhibitors or ARBs had a 30 percent decrease in their PTSD symptom scores. In particular, people taking ACE inhibitors or ARBs tended to have lower levels of hyperarousal and intrusive thoughts.

However, no a reduction in PTSD was seen for those taking other types of blood pressure medications, including beta-blockers.

Both ACE inhibitors and ARBs interfere with angiotensin II, a hormone that regulates blood pressure. Ressler said his laboratory has begun investigating, in mice, the role of angiotensin II in regions of the brain important in stress and fear responses, such as the amygdala.

The new study suggests this class of medication may both decrease the body's physiological response to stress in the cardiovascular system, as well as decrease the brain's response to stress.

Pass it on: Some blood pressure medications may improve symptoms of PTSD, early research suggests.

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