Hyperarousal Symptoms in Survivors of Cardiac Arrest Are Associated With 13 Month Risk of Major Adverse Cardiovascular Events and All-Cause Mortality

Abstract

Abstract Background Key dimensions of cardiac arrest-induced posttraumatic stress disorder (PTSD) symptoms include reexperiencing, avoidance, numbing, and hyperarousal. It remains unknown which dimensions are most predictive of outcome. Purpose To determine which dimensions of cardiac arrest-induced PTSD are predictive of clinical outcome within 13 months posthospital discharge. Methods PTSD symptoms were assessed in survivors of cardiac arrest who were able to complete psychological screening measures at hospital discharge via the PTSD Checklist-Specific scale, which queries for 17 symptoms using five levels of severity. Responses on items for each symptom dimension of the four-factor numbing model (reexperiencing, avoidance, numbing, and hyperarousal) were converted to Z-scores and treated as continuous predictors. The combined primary endpoint was all-cause mortality (ACM) or major adverse cardiovascular events (MACE; hospitalization for myocardial infarction, unstable angina, heart failure, emergency coronary revascularization, or urgent defibrillator/pacemaker placements) within 13 months postdischarge. Four bivariate Cox proportional hazards survival models evaluated associations between individual symptom dimensions and ACM/MACE. A multivariable model then evaluated whether significant bivariate predictors remained independent predictors of the primary outcome after adjusting for age, sex, comorbidities, premorbid psychiatric diagnoses, and initial cardiac rhythm. Results A total of 114 patients (59.6% men, 52.6% white, mean age: 54.6 ± 13 years) were included. In bivariate analyses, only hyperarousal was significantly associated with ACM/MACE. In a fully adjusted model, 1 standard deviation increase in hyperarousal symptoms corresponded to a two-times increased risk of experiencing ACM/MACE. Conclusions Greater level of hyperarousal symptoms was associated with a higher risk of ACM/MACE within 13 months postcardiac arrest. This initial evidence should be further investigated in a larger sample.