Illness perception and fatigue after myocardial infarction

摘要

Treatment of myocardial infarction (MI) has undergone major advances in recent years, including reductions in mortality and hospital stays. To optimize patients’ recovery, secondary preventive strategies are important. However, many patients fail to attend to such programmes. It has been shown that illness perceptions may influence attendance to rehabilitation programmes as well as recovery. Other obstacles are post-MI fatigue and depression. The main focus of the present thesis was to explore illness perception and fatigue after MI. A secondary aim was to investigate the levels of illness perceptions and fatigue and their relationships with demographic/clinical variables, depression, anxiety and health-related quality of life (HRQoL). In Study I, patients’ illness perception of MI was explored. The methodology used was grounded theory (25 informants interviewed). The core categories illness reasoning and trust in oneself vs. trust in others were found to be fundamental in viewing the MI either as an acute isolated heart attack or as a sign of a chronic condition. In Study II, the aim was to gain a deeper understanding of what fatigue means to patients with recent MI and how they managed to deal with the consequences of fatigue. Grounded theory was applied also in this study (19 informants interviewed). A central theme was labelled living with incomprehensible fatigue. This core category was featured by several properties: different kind of tiredness, unrelated to effort, unpredictable occurrence, and unknown cause. In Study III, the incidence of fatigue in 204 consecutive MI patients was examined and compared to reference populations. Gender differences in fatigue were also examined, as well as changes over time and the relationships between fatigue versus clinical and demographic variables and measures of emotional distress. The Hospital Anxiety and Depression Scale (HADS) and the Multidimensional Fatigue Inventory (MFI-20) were used. MI patients reported higher levels of fatigue compared with the general population, depression and fatigue overlapped, but 33% reported fatigue without coexisting depression. No gender differences were found. In Study IV, illness perceptions in 204 consecutive MI patients were examined using the Illness Perception Questionnaire (IPQ-R) and compared to reference populations. Changes in illness perceptions over time were also examined, as well as the relationships between illness perceptions and anxiety/depression (HADS), fatigue (MFI-20), somatic health problems (SHCQ) and HRQoL (SF-36). It was shown that illness perceptions changed over time, from viewing the MI as an acute event to a more chronic condition, and that the beliefs in personal and treatment control of MI decreased. These negative beliefs were associated with fatigue and lowered HRQoL. In conclusion, the studies contribute to our understanding of how patients perceive their MI, and particularly that fatigue is a notable symptom affecting patients´ lives. Individualized secondary preventive strategies could start with identifying patient’s unique illness perception. It is also important to identify patients who are fatigued to provide adequate treatment as well as to prevent progression from fatigue to exhaustion.