Acute stress disorder after myocardial infarction: prevalence and associated factors

To examine the prevalence of acute stress disorder (ASD) after a myocardial infarction (MI) and the factors associated with its development.

Of 1344 MI patients admitted to three Canadian hospitals, 474 patients did not meet the inclusion criteria and 393 declined participation in the study; 477 patients consented to participate in the study. A structured interview and questionnaires were administered to patients 48 hours to 14 days post MI (mean +/- standard deviation = 4 +/- 2.73 days).

Four percent were classified as having ASD using the Structured Clinical Interview for DSM-IV, ASD module. The presence of symptoms of depression (Beck Depression Inventory; odds ratio (OR) = 29.92) and the presence of perceived distress during the MI (measured using the question "How difficult/upsetting was the experience of your MI?"; OR = 3.42, R(2) = .35) were associated with the presence of symptoms of ASD on the Modified PTSD Symptom Scale. The intensity of the symptoms of depression was associated with the intensity of ASD symptoms (R = .65). The models for the detection and estimation of ASD symptoms were validated by applying the regression equations to 72 participants not included in the initial regressions. The results obtained in the validation sample did not differ from those obtained in the initial sample.

The symptoms of depression and the subjective distress during the MI could be used to improve the detection of ASD.