Cardiac Self-Efficacy and Fatigue One Year Post-Myocardial Infarction

Background: Patients and clinicians report that fatigue post-myocardial infraction (MI) is a bothersome symptom during recovery. Aim: The objective of this study was to explore whether there is a relationship between fatigue, cardiac self-efficacy, stress, breathlessness and physical activity one year post-MI. Method: Data were collected from a sample of patients diagnosed with MI one year earlier (n = 125) who responded to a questionnaire package measuring fatigue, cardiac self-efficacy, physical activity and the symptoms breathlessness and stress. Correlation and regression analyses were preformed to evaluate which factors were related to fatigue. Results: The results showed that cardiac self-efficacy was associated with fatigue (r = −0.611, p = 0.01) and the regression model, controlling for breathlessness and stress, showed an explained variance of 72% one year post-MI. Physical activity was not significant in this model and did not predict fatigue during this time period. Conclusion: Post-MI fatigue-relief support should rely not only on identification of fatigue and other concurrent symptoms, but also on identification of cardiac self-efficacy.

Development of a Tool for Assessment of Post-Myocardial Infarction Fatigue

Introduction: After treatment for myocardial infarction (MI) quite a few persons will experience different symptoms, including fatigue, during the recovery phase. The aim of the present study was to construct the multidimensional Post-Myocardial Infarction Fatigue (PMIF) scale, based on empirical data gathered in coronary heart disease contexts. Methods: The construction of the post-MI fatigue scale was conducted in seven steps, ending in a psychometric evaluation of the internal structure of the scale, using confirmatory factor analysis, as well as testing of convergent and discriminant validity, using correlational analysis, in a sample of 141 persons treated for MI. Results: The results showed that the PMIF scale represents three dimensions: physical, cognitive and emotional fatigue. It was also found that the scale is suitable for summing the items to obtain a total score representing a post-MI global fatigue dimension. Conclusion: The PMIF is a brief and easily completed scale for identifying persons experiencing post-MI fatigue. Early identification of fatigue, together with health behavior support, might prevent progression toward a more severe state of fatigue.

The Single-Item Measure of Stress Symptoms after Myocardial Infarction and Its Association with Fatigue

Surviving a myocardial infarction (MI) can be a stressful event entailing challenges in daily life during the recovery period. Experiencing fatigue symptoms post-MI has been described as bothersome and occurs in nearly half of patients four months and two years after MI. The aetiology of fatigue disorder is unclear, but research has shown that fatigue plays an important role in the relationship between stress and perceived poor health. Previous findings indicate that having access to an easily administered stress measurement is worthwhile both in the clinic and in research. The single-item measure of stress symptoms has not been validated in persons treated for MI. The aim was to validate the single-item measure of stress symptoms and to explore its association with fatigue in a sample of persons treated for MI. Methods: 142 respondents completed the questionnaires of the Multidimensional Fatigue Inventory-20, the single-item measure of stress symptoms and the Perceived Stress Scale-10 (PPS-10) two months post-MI. Correlation analysis and t-tests were used to validate the single-item stress measure and its association with post-MI fatigue. Results: The convergent validity of the single-item measure of stress symptoms was confirmed. In analyses of relations between stress and fatigue, it was found that the single-item stress measure was strongly associated with both the global fatigue score and all four fatigue dimension scores (general, physical and mental fatigue as well as reduced activity). Conclusion: The single-item measure of stress symptoms was found to be a valid measure of post-MI stress. Also, the measure was useful in assessing associations between stress and fatigue and could therefore indicate that post-MI fatigue experiences should be further explored in full using multidimensional fatigue assessment.