Illness perception and the associated outcomes among acute myocardial infarction patients receiving different treatment modalities : a mixed-methods approach

Background: Treatment for acute myocardial infarction (AMI) differs according to presentation, and there are claims in the literature that this may impact on patients' understanding of the diagnosis 'and subsequent behavioural changes. Aim: to determine if the treatment modality had an impact on illness perception and secondary prevention outcomes across 3 different treatment groups - I. ST-Elevation Myocardial Infarction (STEMI) treated by PPCI, II. STEMI treated by thrombolytic therapy (THROMB), and III. Non ST-Elevation Myocardial Infarction (NSTEMI) treated by medication. Methods: A mixed-methods, repeated-measure design was used to collect data from a cross-sectional sample of Jordanian patients during hospitalisation and 6 months later. Instruments were Illness Perception Questionnaire, Coping Response Inventory, Hospital Anxiety and Depression Scale, and SF-36. Leventhal's self-regulatory model (SRM) informed the variables used in the path analysis and the interview schedule. Path Analysis assessed the causal relationship between the variables based on SRM. Results: In the 186 patients who completed questionnaires at both time points baseline, ANOVA showed no Significant differences in illness perception or anxiety and depression. Those treated with THROMB had significantly higher cognitive approach coping compared to the other groups (P 0.001), and PPCI had significant higher quality of life compared to the other groups (P 0.001). Confirmatory Factor Analysis confirmed the reliability of the questionnaires. Six months after hospitalisation, Paired t-tests showed that PPCI patients had significantly lower personal control (p 0.029), and higher perception of treatment control (P 0.001) and illness coherence (P 0.034) compared to baseline. However, there were no significant changes in the other four illness perception factors, anxiety and depression, coping factors, and general health factors. Examining the outcomes of behavioural change using Mc Nemar's test showed that THROMB patients had significant higher control of cholesterol (P 0.02), PPCI patients had lower control of blood pressure (P 0.013), and each group had significant lower smoking status (P 0.05 for PPCI, P 0.001 for THROMB, and P 0.008 for NSTEMI). Wilcoxon test shows THROMB patients had significantly (P 0.001) higher activity level. However, there were no significant changes in body mass index and low density lipoprotein in any group. Path Analysis of the SRM concluded that the model failed to explain the relationships between factors as theoretically construed. The qualitative thematic analysis of 14 patients' semi-structured interviews at both baseline and follow-up times cannot demonstrate differences between the treatment modalities. Conclusion: While these quantitative results do show some significant differences between the three treatment modalities in terms of illness perception and behavioural change, this did not follow a consistent pattern and the majority of the factors had no significant differences. Consistent with this, the qualitative part of the study did not show differences between the three treatment modalities in illness perception or risk factor modification. While we must conclude that treatment modality did not impact on patients' illness perception or on behavioural outcomes, further research in this population is warranted.EThOS - Electronic Theses Online ServiceGBUnited Kingdo