Personality and mortality after myocardial infarction

Previous research showed: a) emotional distress is a risk factor for mortality after myocardial infarction (MI) and b) emotional distress is linked to stable personality traits. In this study, we examined the role of these personality traits in mortality after MI. Subjects were 105 men, 45 to 60 years of age, who survived a recent MI. Baseline assessment included biomedical and psychosocial risk factors, as well as each patient's personality type. After 2 to 5 (mean, 3.8) years of follow-up, 15 patients (14%) had died. Rate of death for patients with a distressed personality type (11/28 = 39%) was significantly greater than that for patients with other personality types (4/77 = 5%) (p < .0001). Patients with this personality type tend simultaneously to experience distress and inhibit expression of emotions. Low exercise tolerance, previous MI (p < .005), anterior MI, smoking, and age (p < .05) were also associated with mortality. A logistic regression model including these biomedical factors had a sensitivity for mortality of only 27%. The addition of distressed personality type in this model more than doubled its sensitivity. Of note, among patients with poor physical health, those with a distressed personality type had a five-fold mortality risk (p < .005). Consistent with the findings of other investigators, depression (p < .005), life stress, use of benzodiazepines (p < .01), and somatization (p < .05) were also related to post-MI mortality. These psychosocial risk factors were more prevalent in the distressed personality type than in the other personality types (p < .001-.05). Multiple logistic regression indicated that these psychosocial factors did not add to the predictive value of the distressed personality type. Hence, an important personality effect was observed despite the low power. This suggests that personality traits may play a role in the detrimental effect of emotional distress in MI patients.