Disgust in colorectal cancer contexts: Does it cause avoidance and could mindfulness help?

Abstract

Disgust’s evolved function is to minimise health threats through a process of rejection, avoidance, and withdrawal. Despite its seemingly obvious relevance, however, research investigating disgust in physical health settings remains scant. By exploring the emotion of disgust in the context of colorectal cancer, the current work sought to address this research deficit, and in doing so, add to the emerging literature examining the emotional bases of avoidance in health. The colorectal cancer trajectory presents numerous established disgust elicitors (faeces, surgical wounds, anal investigations, etc.), and avoidance can have serious physical and psychological consequences. Thus, the aims of this work were to establish: (1) whether disgust predicts and/or causes avoidance in colorectal cancer contexts, and if so, (2) consider whether mindfulness may help to ameliorate this effect? Following a systematic review of literature pertaining to colorectal cancer and disgust, a series of correlational and experimental studies in clinical and non-clinical populations were conducted. The first of these empirical works—Study 1, a prospective, correlational design with anal incontinence patients—found that greater disgust sensitivity predicted poorer psychological and environmental well-being, and moderated the link between symptom severity and outcome. In Study 2a, trait disgust predicted, and experimentally-induced disgust caused, greater immediate avoidance behaviours related to colorectal cancer. In addition, trait disgust increased the influence of state disgust on decisions regarding anticipated future avoidance. With the relationship between disgust and avoidance established, the focus of this work then turns to consider whether mindfulness might ameliorate disgust’s effects. Data from the prior study was revisited in Study 2b, and contrary to expectations, analyses showed that greater trait mindfulness exaggerated avoidance behaviours rather than diminishing them. Similarly, Study 3—an experimental study in which both disgust and mindfulness were experimentally induced—found that state disgust caused social avoidance in relation to bowel health scenarios and, again, state mindfulness exaggerated the effect. Finally, Study 4, a randomised controlled trial with first time chemotherapy patients, found that a brief mindfulness intervention led to detrimental effects—greater distress and increased social avoidance—in comparison to relaxation training. Taken together, these studies are the first to clearly demonstrate that (a) disgust both predicts and causes avoidance in contexts related to colorectal cancer, and (b) that mindfulness does not ameliorate disgust’s effects, at least in these contexts. This thesis thus highlights the importance of considering the emotion of disgust in both colorectal cancer and in physical health settings more broadly, and has important clinical implications. Through better understanding of a key affective mechanism of avoidance (i.e., the disgust response), these findings have potential to inform interventions designed to reduce deleterious avoidance. This work ends on a note of caution, suggesting that mindfulness-based interventions may not be optimally suited to some physical health populations, and suggests alternative potential avenues for future research and clinical intervention.