Duration of, and temporal trends (1994-1997) in, prehospital delay in patients with acute myocardial infarction - The Second National Registry of Myocardial Infarction

Background: Extent of delay in seeking medical care in persons with acute m yocardial infarction (AMI) is receiving increasing attention, given the tim e-dependent benefits associated with early administration of coronary reper fusion therapy. Objective: To examine recent data, and temporal trends therein, about durat ion of prehospital delay in a large (N = 364131) cross-sectional sample of patients included in the second National Registry of Myocardial Infarction. Methods: The medical records of patients hospitalized with AMI in 1624 US h ospitals from June 1, 1994, to October 31, 1997, were reviewed for informat ion about duration of prehospital delay. Results: There was evidence of a slight decline in average delay times in p atients hospitalized in 1997 (5.5 hours) compared with those hospitalized i n 1994 (5.7 hours). Median delay times (2.1 hours) did not change. Approxim ately 20% of patients presented to the hospital within 1 hour of acute symp tom onset, and slightly more than two thirds presented within 4 hours. Dela y times were more prolonged for older patients, women, nonwhite patients, a nd patients with a history of diabetes or hypertension vs respective compar ison groups. Patients in cardiogenic shock exhibited shorter delay times th an less severely ill patients. Patients with previous AMI or who had underg one previous coronary angioplasty presented to the hospital with shorter de lay times, as did individuals hospitalized in the Mountain and Pacific regi ons. Conclusions: These results provide insights into recent delay times and int o groups at risk for prolonged delay.