Posttraumatic stress disorder (PTSD) is prevalent among patients who survived an acute coronary syndrome and is associated with adverse outcomes, but the mechanisms underlying these associations are unclear.
To evaluate the association of PTSD with mental stress-induced myocardial ischemia among individuals who survived a myocardial infarction (MI).
This cross-sectional study included 303 patients aged 18 to 60 years enrolled from a university-affiliated network. Participants had a verified history of MI within 8 months. Data were collected from June 2011 to March 2016, and data analysis was conducted from March to June 2019.
A clinical diagnosis of PTSD (lifetime and current) was obtained using the Structured Clinical Interview from the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition), and PTSD symptom subscales were assessed with the civilian version of the PTSD Symptom Checklist.
Patients received technetium 99m-labeled sestamibi myocardial perfusion imaging at rest, with mental stress (ie, a speech task) and conventional stress (ie, exercise or pharmacologic). A summed difference score (ie, the difference between stress and rest scores) was used to assess ischemia under both stress conditions.
Among 303 participants (148 [48.8%] women; 198 [65.3%] African American; mean [SD] age, 51 [7] years), the prevalence of PTSD was 14.5% (44 patients). Patients with PTSD had a higher rate of ischemia with mental stress than those without PTSD (12 of 44 [27.3%] vs 38 of 259 [14.7%]; P = .04) and more than twice the mean number of ischemic segments (1.2 [95% CI, 0.5-1.8] vs 0.5 [95% CI, 0.3-0.7]; P < .001), but there was no difference in conventional stress ischemia (10 of 44 [22.7%] vs 60 of 259 [23.2%]; P = .91). Increasing levels of PTSD symptoms were associated with higher odds of ischemia with mental stress (adjusted odds ratio [OR] per 5-point score increase, 1.18; 95% CI 1.04-1.35; P = .01) but not with conventional stress (adjusted OR per 5-point score increase, 1.05; 95% CI, 0.92-1.21; P = .47). Reexperiencing trauma was the symptom cluster most robustly associated with the presence of ischemia with mental stress (adjusted OR per 5-point score increase, 1.87; 95% CI 1.21-2.91; P = .005), followed by avoidance and numbing (adjusted OR per 5-point score increase, 1.51; 95% CI, 1.07-2.14; P = .02).
In this study of young and middle-aged individuals with MI, with a large representation of women and patients from racial/ethnic minority groups, PTSD was associated with the development of myocardial ischemia with mental stress. A higher ischemic response to mental stress represents a potential pathway associating PTSD with adverse outcomes after MI.