Use of emergency medical services for suspected acute cardiac ishemia among demographic and clinical patient subgroups: The REACT trial

Objective. Barriers to the use of emergency medical services (EMS) and patient delay in seeking care can limit the receipt or effectiveness of reperfusion therapies and the availability of prehospital emergency cardiac care. The Rapid Early Action for Coronary Treatment (REACT) trial was designed to determine the impact of a community intervention on use of EMS among demographic and clinical subgroups of patients with suspected acute cardiac ischemia. Methods. A randomized controlled community trial was conducted in 20 pair-matched communities in the United States. One community from each pair received an 18-month, multicomponent community education program. Data were collected at 44 participating hospitals during a four-month baseline period and throughout the 18-month trial, using medical record abstracts to collect information on mode of transport to the hospital and other sociodemographic and clinical variables. Eligible patients were persons aged ≥30 years presenting with chest pain or discomfort to emergency departments (EDs) who were admitted and discharged with a cardiac-related diagnoses (ICD 410-414, 427-429, 440, 786.9). Results. The net change in the odds of EMS use was an increase of 34% in intervention compared with control communities [adjusted odds ratio (OR) 1.34, 95% CI 1.07-1.67]. We observed greater increases in the odds of EMS use among patients who had chronic or other cardiac diagnoses (adjusted OR 1.53, 95% CI 1.18-1.99, and adjusted OR 1.52, 95% CI 1.17-1.97, respectively) than in those diagnosed as having acute ischemia (adjusted OR 1.14, 95% CI 0.91-1.44). We observed greater increases in odds of EMS use in those who were retired (adjusted OR 1.62, 95% CI 1.29-2.04) or had systolic blood pressure (SBP) at or below 160 mm Hg upon presentation to the ED (adjusted OR 1.55, 95% CI 1.26-1.91 for SBP 100-160 mm Hg; 1.61, 95% CI 0.88-2.97 for SBP <100 mm Hg). Conclusions. The REACT trial demonstrated a significant impact on the use of EMS among patients admitted to the hospital for suspected acute myocardial infarction, with greater increases among patients with chronic or other cardiac ICD-9 discharge diagnoses, those presenting with lower SBP, and retired persons.