Adventures in the Land of Diagnosis: Exploring the Psychological Implications of Positive and Negative Diagnosis Following Advanced Cardiac Testing Procedures

Abstract

Advanced cardiac testing procedures such as conventional coronary angiography and coronary CT angiography offer precise diagnostic methods for investigating the presence of underlying ischaemic heart disease. As such, these tests can have important consequences for patients undergoing them, as definitive results can lead to treatment for underlying disease, on the one hand, and the provision of reassurance that symptoms are not of cardiac origin on the other. The amount of psychological research in this area does not, however, reflect the frequency with which these tests are utilised in medicine. Three studies were conducted into the psychological implications of diagnosis in the context of these cardiac imaging tests. The first study tested the efficacy of a brief pre-testing intervention aimed at enhancing reassurance among non-acute chest pain patients referred for diagnostic coronary angiography. Previously shown to be effective in another cardiac testing environment, the intervention involved the administration (plus discussion) of preparatory information regarding the implications of receiving normal cardiac test results. Although the results failed to show any differences in reassurance levels between the intervention group and treatment-as-usual controls, the study nonetheless raised considerations around the practicability of conducting interventions in angiogram settings and among patients with noncardiac chest pain. Supplementary analysis found that patients with lower levels of reassurance were more likely to have higher trait anxiety and more negative illness perceptions, with illness identity being the most important. The second study explored the psychological impact of diagnostic test results from a coronary CT angiogram with respect to two particular domains: (1) effects on patients‘ illness perceptions and (2) effects on health behaviour intentions and subsequent health behaviours. Study results were dependent on the diagnosis itself, with negative-testing patients reporting post-testing decreases in illness perceptions (e.g., concern, consequences and emotion) in comparison to positive-testing patients, who showed no change on these variables. Conversely, only positive-testing patients showed increases in intentions to take cardiac medication as well as intentions to exercise following testing, which was backed up by increased physical activity at 6-week follow-up. These findings show that, first, patients cognitively prepare themselves for an unfavourable diagnosis and, second, coronary CT angiography has a positive effect on engagement in health-protective behaviours. Other findings showed that both groups reported a higher level of illness coherence following testing and that control beliefs were dependent on testing also, with positive-testing patients scoring higher on treatment control beliefs and negative-testing patients demonstrating stronger beliefs in personal control over their illness. The third study was a qualitative investigation into patients‘ impressions of and reactions to coronary CT angiography. Prediagnostic interviews revealed that patients had expectations of gaining knowledge and understanding from testing and that testing was the sine qua non for taking cardiac medication. Post-diagnostic interviews revealed themes relating to patients‘ generally positive reactions to testing and their appreciation of seeing their heart images, which helped in their heart-related understanding. Additionally, patients communicated increased motivation to maintain or increase heart-healthy behaviours following testing. Taken together, the results of all three studies raise points of discussion relating to the search for more effective means of enhancing reassurance, the delineation of the effects testing can have on patients‘ illness appraisals and health behaviour, and the beneficial aspects of using patients‘ scan images to facilitate the post-diagnostic consultation. The work of this thesis therefore extends current understanding of the psychological implications of cardiac diagnosis, provides direction for further research in this area, and offers guidance for future clinical practice.