Background: Many anecdotes and several uncontrolled case series have suggested that emotionally stressful events, and more specifically, anger, immediately precede and appear to trigger the onset of acute myocardial infarction. However, controlled studies to determine the relative risk of myocardial infarction after episodes of anger have not been reported.
Methods and results: We interviewed 1623 patients (501 women) an average of 4 days after myocardial infarction. The interview identified the time, place, and quality of myocardial infarction pain and other symptoms, the estimated usual frequency of anger during the previous year, and the intensity and timing of anger and other potentially triggering factors during the 26 hours before the onset of myocardial infarction. Anger was assessed by the onset anger scale, a single-item, seven-level, self-report scale, and the state anger subscale of the State-Trait Personality Inventory. Occurrence of anger in the 2 hours preceding the onset of myocardial infarction was compared with its expected frequency using two types of self-matched control data based on the case-crossover study design. The onset anger scale identified 39 patients with episodes of anger in the 2 hours before the onset of myocardial infarction. The relative risk of myocardial infarction in the 2 hours after an episode of anger was 2.3 (95% confidence interval, 1.7 to 3.2). The state anger subscale corroborated these findings with a relative risk of 1.9 (95% confidence interval, 1.3 to 2.7). Regular users of aspirin had a significantly lower relative risk (1.4; 95% confidence interval, 0.8 to 2.6) than nonusers (2.9; 95% confidence interval, 2.0 to 4.1) (P < .05).
Conclusions: Episodes of anger are capable of triggering the onset of acute myocardial infarction, but aspirin may reduce this risk. A better understanding of the manner in which external events trigger the onset of acute cardiovascular events may lead to innovative preventive strategies aimed at severing the link between these external stressors and their pathological consequences.