Cardiac patients' perceptions of neighboring patients' risk: influence on psychological stress in the ED and subsequent posttraumatic stress.

Background: As many as 12% of acute coronary syndrome (ACS) patients screen positive for post-traumatic stress disorder (PTSD) symptoms due to their cardiac event, and emergency department (ED) factors such as overcrowding have been associated with risk for PTSD. We tested the association of patients' perceptions of their proximity to a critically ill patient during ED evaluation for ACS with development of posttraumatic stress symptoms (PSS) in the month after hospital discharge.

Methods: Participants were enrolled in the REactions to Acute Care and Hospitalization (REACH) study during evaluation for ACS in an urban ED. Participants reported whether they perceived a patient near them was close to death. They also reported their current fear, concern they may die, perceived control, and feelings of vulnerability on an Emergency Room Perceptions questionnaire. One month later, participants reported on PTSD symptoms specific to the cardiac event and ED hospitalization.

Results: Of 763 participants, 12% reported perceiving a nearby patient was likely to die. In a multivariate linear regression model [F(9757) = 19.69, p < .001, R adjusted = .18] with adjustment for age, sex, GRACE cardiac risk score, discharge ACS diagnosis, Charlson comorbidity index, objective ED crowding, and depression symptoms at baseline, perception of a nearby patients' likely death was associated with a 2.33 point (95% CI, 0.60-4.61) increase in 1 month PTSD score. A post hoc mediation analysis with personal threat perceptions [F(10,756) = 25.28, p < .001, R adjusted = .24] showed increased personal threat perceptions during the ED visit, B = 0.71 points on the PCL per point on the personal threat perception questionnaire, β = 0.27, p = .001, fully mediated association of participants' perceptions of nearby patients' likely death with 1-month PTSD score (after adjustment for ED threat perceptions,) B = 0.89 (95% CI, -1.33 to 3.12), β = 0.03, p = .43, accounting for 62% of the adjusted effect and causing the main effect to become statistically nonsignificant.

Conclusions: We found patients who perceived a nearby patient was likely to die had significantly greater PTSD symptoms at 1 month. Awareness of this association may be helpful for designing ED patient management procedures to identify and treat patients with an eye to post-ACS psychological care.