Since the advent of thrombolytic therapy, early treatment holds particular promise for decreasing mortality from coronary heart disease. Thrombolytic therapy can reduce mortality by 25 percent for patients treated within the first few hours of AMI symptoms, with greater benefit the earlier the treatment. Not everyone who could benefit from receiving thrombolytic therapy receives such therapy. One contributing factor is that many people with symptoms do not seek emergency care in a timely manner. Studies show substantial delay times from AMI symptoms to hospital arrival, with means ranging from 4.6 to 24 hours and medians from 2 to 6.4 hours. EMS transport time is estimated to average 7 to 22 minutes, so a large portion of pre-hospital delay is attributable to patient recognition and action. Several factors have been associated with delay time. Sudden onset pain is associated with shorter delay times, and older age, female gender, African-American race, consultation with others about symptoms, and self-treatment programs are associated with longer delay times. There is a need for educational programs that are effective in decreasing delay times, particularly by focusing on people who are at increased risk of having an AMI and groups more likely to delay seeking treatment.
Community interventions to reduce delay time between AMI symptoms and contact with the medical system have been conducted in Britain, Canada, Sweden, Australia, Germany, King County in Washington, and Jacksonville, Illinois. The interventions have been promising, but the studies suffer from problems that make the reported results difficult to interpret. Almost all the published studies assessed delay time pre-to-post intervention and had no control or comparison group, making the magnitude and significance of impact from the intervention difficult to determine. Most were conducted in countries other than the United States, so applicability to the health-care system in the United States is questionable. Although some examined the effect of a public education program on ambulance and ED utilization, the effects of public education campaigns on use of the EMS or ED remains unanswered.
The study was a multicenter, controlled community trial where the community was the unit of assignment and of analysis. Twenty study communities were pair-matched on demographics and one of each pair was randomly assigned to intervention and one to control. The intervention communities received an 18-month community-based intervention to reduce delay time for symptoms and signs of AMI, focusing on decreasing the delay time associated with patient recognition and action. Several methods were used including: educational interventions based on behavior change theory; patient and provider education; public education and community organization. The primary outcome was time from symptom onset to arrival at the emergency department. Data collection and intervention continued until competion of 18 months of intervention.