PTSD and Heart Disease: New Data Help Clarify the Connection

In a study published this month in The Journal of the American College of Cardiology, posttraumatic stress disorder (PTSD) emerged as a novel risk factor for coronary artery disease, independent of major depression. This was a prospective study of 562 twins (281 pairs) with a mean age of 42.6 years who did not have a self-reported history of coronary heart disease (CHD) at baseline. Twin pairs were selected from the Vietnam Era Twin Registry based on discordant clinical histories of PTSD and major depression, and pairs with neither condition. There were 137 veterans who had received a diagnosis of PTSD.

After a median of 13 years of follow-up, the incidence of CHD (as evidenced by clinical events of myocardial infarction, other hospitalizations for CHD, and coronary revascularization) was more than double in twins with PTSD than those without PTSD after adjusting for lifestyle factors, other CHD risk factors, and major depression (OR = 2.2; 95% confidence interval, 1.2 to 4.1; P = .01). Quantitative measures of coronary perfusion, such as stress total severity score (STSS) and coronary flow reserve (CFR) were also worse in twins with PTSD than those without, although the CFR association became nonsignificant after adjusting for risk factors and major depression. This relationship was slightly attenuated in discordant twins although it remained significant.

Previous studies have linked PTSD with higher blood pressure, unfavorable catecholamine profiles, higher incidence of smoking, higher levels of inflammatory markers, insulin resistance, and metabolic syndrome, as well as other CHD risk factors.

But, this was the first study to link PTSD to coronary heart disease using both myocardial perfusion criteria as well as clinical criteria. Furthermore, the use of the co-twin design in this study was able to account, at least in part, for unmeasured genetic confounders. Therefore, it offers a stronger level of evidence than previous observational studies, some of which have revealed inconsistent results.  

Although this study was able to adjust for many underlying differences, the primary pathophysiological mechanism for this relationship remains unclear. Additional studies are needed to determine whether routine screening for PTSD or incorporating a history of PTSD in risk estimations for CHD should be routinely done.

Reference:
Vaccarino V, Goldberg J, Rooks C, et al. Posttraumatic stress disorder and incidence of coronary heart disease: a twin study.  J Am Coll Cardiol. doi:10.1016/j.jacc.2013.04.085. (Abstract)