Symptom Trajectories After Emergency Department Visits for Potential Acute Coronary Syndrome

Background: Many patients evaluated for acute coronary syndrome (ACS) in emergency departments (EDs) experience ongoing or recurrent symptoms after discharge, regardless of their ultimate medical diagnosis. A comprehensive understanding of post-ED symptom trajectories is lacking. Aims: Aim 1 was to determine trajectories of severity of common symptoms (chest pressure, chest discomfort, unusual fatigue, chest pain, shortness of breath, lightheadedness, upper back pain and shoulder pain) in the six months following an ED visit for potential ACS. Aim 2 was to identify relationships between symptom trajectories and baseline physiologic factors (age, gender, diabetes status, diagnosis, comorbidities, functional status) and situational factors (marital status, insurance status, education level). Aim 3 was to identify relationships between symptom trajectories and health service use (outpatient visits and calls, ED visits, 911 calls, hospitalization) in the six months after the ED visit. Methods: This was a secondary data analysis from a study conducted in five U.S. EDs. Patients (n=1002) who had abnormal electrocardiogram or biomarker testing and were identified by the triage nurse as potentially having ACS were enrolled. Symptom severity was assessed in the hospital and 30 days and six months post-discharge using the 13-item ACS Symptom Checklist. Symptom severity was modeled across the three study time points using growth mixture modeling. Model selection was based on interpretability, theoretical justification, and statistical fit indices. Patient characteristics were used to predict trajectories using logistic regression and differences in health service use were tested using chi-square analysis. Results: Between two and four distinct trajectory classes were identified for each symptom. Identified trajectories were labeled "tapering off," "mild/persistent," "moderate/persistent," "moderate/worsening," "moderate/improving," "late onset," and "severe/improving." Age, se