Women who are exposed to trauma or have posttraumatic stress disorder (PTSD) may have an increased risk for cardiovascular disease, according to a 20-year observational analysis of female nurses in the U.S.

Specifically, the analysis found that women both with trauma and at least four PTSD symptoms as well as trauma victims with no symptoms at all were at elevated risk, according to Jennifer A. Sumner, PhD, of Columbia University Mailman School of Public Health in New York, and colleagues, who published their findings online in Circulation on June 29.

“Although it was perhaps a little surprising that the women who reported trauma but no PTSD symptoms on our screening questionnaire exhibited elevated risk, this is somewhat consistent with other findings in the literature,” Sumner told Cardiovascular Business. “We’re suggesting that trauma exposure is associated with negative consequences for physical health even when you account for a variety of different psychiatric conditions like depression and posttraumatic stress disorder. There is a growing body of evidence suggesting that just trauma exposure can have negative consequences for one’s physical health down the line.”

To determine the relationship between PTSD and cardiovascular disease, Sumner and colleagues analyzed the Nurses’ Health Study II, an ongoing study of female nurses who were between 25 and 42 years old when the trial began in 1989.

“These are women who are drawn from the general population who were exposed to a variety of traumatic events, not just combat exposure as you would usually get in veterans’ samples,” Sumner said.

In 2008, the researchers mailed a questionnaire to 60,804 of the women asking them about trauma exposure and PTSD symptoms. They received complete responses from 54,282 women.

To measure trauma exposure, they used the 16-item modified version of the Brief Trauma Questionnaire, which included assessments of their exposure to 15 traumatic events such as a natural disaster, unwanted sexual exposure or physical assault. They also used the seven-item Short Screening Scale to assess seven PTSD symptoms. Sumner said a score of 4 indicated the person likely had PTSD.

Between 1989 and 2009, there were 548 cardiovascular events in the cohort, including 277 cases of MI and 271 strokes. During the study, participants were asked every two years if they had physician-diagnosed MI or stroke.

After adjusting for demographic, family history and childhood factors, nurses who experienced trauma but no PTSD symptoms had a 45 percent higher rate of a cardiovascular event compared with nurses who had no trauma exposure. Nurses who experienced trauma and at least four PTSD symptoms had a 60 percent higher rate of MI or stroke.

Surprisingly, nurses who had trauma and one to three symptoms did not have an increased risk for cardiovascular disease. The authors noted a wide confidence interval in this group, however, and said more research is needed to understand the associations of partial PTSD diagnoses with cardiovascular disease.

Nearly 50 percent of the association between elevated PTSD symptoms and cardiovascular disease was accounted for by unhealthy behaviors such as smoking cigarettes and drinking alcohol, according to the authors.

By the end of the 20-year follow-up period, approximately 21 percent of women had no trauma exposure, 47 percent had trauma but no symptoms, 16 percent had trauma and one to three symptoms and 16 percent had trauma and at least four symptoms.

The researchers mentioned that PTSD is twice as common in women as in men. Ten percent of women will develop PTSD during their lifetime, according to Sumner, who added that cardiovascular disease is the leading cause of death in women.

Sumner said a limitation of the study was that 94 percent of the participants were white and were less likely to smoke or consume excessive amounts of alcohol compared with the general population.

Still, the researchers plan on evaluating biologic, mechanistic pathways in these patients and examining how cardiovascular-related biomarkers change over time as a function of trauma exposure and PTSD symptoms.

“We still think that we can make some interesting conclusions from this sample,” Sumner said. “It’s also interesting that we find these associations of increased risk even in a more healthy sample.”