PTSD is common in the general population. Approximately 7% of Americans will meet diagnostic criteria for PTSD in their lifetime.18 Prevalence rates are much higher among war veterans; in a recent study, 13% of US military personnel who served in Iraq screened positive for PTSD.19 If PTSD is demonstrated to have significant cardiotoxic effects, there are numerous implications for both prevention and treatment.
More conclusive evidence of the association may be obtained using a variety of approaches. A first step will be to obtain longitudinal data in more diverse samples. This will include considering other groups (ie, women), individuals with clinically significant PTSD, and individuals with non-combat-related PTSD. Additional work will further examine exactly the duration or chronicity of PTSD necessary to initiate pathophysiological processes. Moreover, it is unknown whether the cardiotoxic effects of PTSD can be reversed if PTSD is successfully treated. Future work may compare long-term cardiac outcomes between individuals with PTSD who were successfully treated and those whose PTSD was refractory to treatment. A more careful examination of biological mechanisms is also required. Numerous studies have linked other types of chronic emotional distress with altered vagal tone, increased rate of atherosclerosis, and inflammation, suggesting these as likely pathways. 9 However, the possibility of acute effects of PTSD should also be considered in light of recent work that found evidence of myocardial stunning in response to extreme emotional distress.20
More conclusive evidence and a better understanding of the mechanisms will increase our ability to identify effective forms of prevention and intervention. Currently, individuals who are at high risk of trauma exposure by virtue of their occupations (eg, police or firefighters) are often screened for PTSD. Work on PTSD and CHD may suggest that these individuals should also be monitored or screened for development of adverse cardiovascular outcomes. Pertinently, this adds to the evidence suggesting that cardiologists may be more effective if they can recognize and manage emotional distress in practice. Emotional distress may increase the risk of developing disease (and sometimes actually presents as cardiac disease). It can also adversely impact on a patient’s prognosis by affecting treatment adherence and shaping the course of the disease.9 With improved prevention and more effective treatment strategies, we have the potential to significantly improve patient outcomes.
Since the original publication of this review, several new studies have been published that uniformly provide additional empirical support for the hypothesis that individuals with higher levels of PTSD symptoms are at increased risk of developing CHD.
ADDITIONAL PROSPECTIVE STUDIES
Population-based study of military veterans
A second prospective study was conducted using a random sample of men less than 65 years of age at follow-up who served in the US Army during the Vietnam War.21 Two measures of PTSD were obtained, one based on criteria from the Diagnostic and Statistical Manual of Mental Disorders, 3rd edition (DSM-III), and a second one using the Keane PTSD scale. After excluding any men with a history of heart disease at baseline and controlling for known coronary risk factors, the researchers found that a diagnosis of PTSD (using the DSM-III measure) more than doubled the risk for early-age heart disease mortality (hazard ratio = 2.25; 95% CI, 1.02–4.95). These results were maintained after controlling for depression and whether or not men actually served in Vietnam or elsewhere, and results were similar when the Keane PTSD measure was used. Compared with the men participating in the Normative Aging Study, this study’s population had generally higher PTSD symptom levels and had a significantly younger average age. Thus, findings from this population-based study of US veterans are highly consistent with earlier findings from a more limited sample within the Normative Aging Study.
Community-based study of civilian women
To address the question of whether effects are constrained to men with military experience (and likely combat exposure) or to older individuals, we recently examined the association between PTSD and CHD in civilian women, again using a prospective study design.22 Past-year trauma and associated PTSD symptoms were assessed using the National Institute of Mental Health Diagnostic Interview Schedule and considered in relation to incident CHD during the 14-year follow-up. After excluding individuals with heart disease at baseline and controlling for known coronary risk factors as well as depression and trait anxiety, we found that women with 5 or more PTSD symptoms had a threefold increase in the risk of incident CHD (odds ratio = 3.21; 95% CI, 1.29–7.98) compared with women with no PTSD symptoms. These findings were unchanged after women with angina were excluded and after known coronary risk factors were controlled for. Women in this study were even younger than the men in the prior prospective studies, with a mean age at baseline of 44.4 years. This study provides evidence that that damaging effects of PTSD symptoms are not limited to military men but are also evident among initially healthy community-dwelling civilian women exposed to non-combat-related trauma.
Together, these studies suggest that PTSD may be involved in the etiology of CHD, as all were meticulous in excluding individuals who might have already had heart disease at baseline.