Patients' knowledge about symptoms and adequate behaviour during acute myocardial infarction and its impact on delay time: Findings from the multicentre MEDEA study.
OBJECTIVE: We aimed to assess whether patients' knowledge about acute myocardial infarction (AMI) has an impact on the prehospital delay-time. METHODS: This investigation was based on 486 AMI patients who participated in the cross-sectional Munich-Examination-of-Delay-in-Patients-Experiencing-Acute-Myocardial-Infarction (MEDEA) study. A modified German-version of the ACS-Response-Index Questionnaire was used. Multivariate logistic-regression models were used to identify factors associated with knowledge-level as well as the impact of knowledge-level on delay-time. RESULTS: High AMI-knowledge shortened median delay-time in men (168[92-509] vs. 276[117-1519] mins, p=0.0069), and in women (189[101-601] vs. 262[107-951]mins, p=0.34). Almost half-of-patients (n=284,58%) demonstrated high AMI-knowledge. High-knowledge were independently associated with male-gender (OR=1.47[1.17-1.85]) and General-Practitioner as a knowledge-source (OR=1.42[1.14-1.77]). Old-age (OR=0.87[0.86-0.89]) and previous AMI-history/stent-placement (OR=0.65[0.46-0.93]) were significantly associated with lower-knowledge. Although the majority (476,98%) correctly recognized at least one AMI-symptom, 69(14.2%) patients correctly identified all AMI-symptoms. Additionally, one-in-three believed that heart-attack is always accompanied with severe chest-pain. Elderly-patients and women were more likely to be less-knowledgeable about atypical-symptoms (p=0.006), present with atypical AMI-presentation (p<0.001) and subsequently experience protracted delay-times (p<0.001). CONCLUSIONS: Knowledge of AMI-symptoms remains to be substandard, especially knowledge of atypical-symptoms. Knowledge is essential to reduce delay-times, but it is not a panacea, since it is not sufficient alone to optimize prehospital delay-times.