Patients with acute myocardial infarction have an inaccurate understanding of their risk of a future cardiac event

Background: Accurate perceptions of future cardiac risk are important to ensure informed treatment choices and lifestyle adaptation in patients following myocardial infarction (MI). The aim of this study was to investigate whether risk perceptions of patients with MI were accurate compared with an established clinical risk model. Methods: Seventy-nine consecutive patients with acute MI admitted to the Coronary Care Unit, Auckland Hospital, completed a questionnaire assessing risk perceptions. Clinical data were used to calculate patients' Thrombolysis In Myocardial Infarction (TIMI) risk scores, a validated predictive model of prognosis. The main outcome measures were the associations between perceived risk, TIMI risk scores and troponin T. Results: Patients' risk perceptions showed no correlation with thrombolysis in myocardial infarction risk scores (r = -0.06; P = 0.61) or with troponin T (r = -0.07; P = 0.53). Patients' risk perceptions were not significantly associated with age or sex, and were not significantly higher in those who had experienced a previous MI, a family history of coronary heart disease, diabetes or smokers. Higher perceived risk was significantly associated with a number of illness perceptions, including worse consequences of the MI and lower beliefs in the benefit of treatment. Patients who overestimated their risk were more anxious than other patients (F(2, 73) = 22.97; P = 0.0001). Conclusion: Patients with MI ideas about their personal risk of future MI are not congruent with their clinical risk assessments. Inpatient hospital care appears to be unsuccessful in communicating prognosis effectively to patients. Improving the accuracy of risk perceptions may help decrease unnecessary cardiac anxiety and invalidism in some patients and prompt risk-reducing behaviours in others.