Illness Perceptions, Coping, and Psychological Outcomes in Patients with Head and Neck Cancer and their Caregivers

Abstract

Patients with head and neck cancer (HNC) often experience enduring impairments in functional ability and appearance as a consequence of their disease. Despite high rates of psychological distress and low levels of health-related quality of life (HRQL) reported by this population and their caregivers, limited research has endeavoured to identify psychological factors that may contribute to variation in these outcomes. Furthermore, few studies have developed and tested psychological interventions to improve adjustment to HNC. Using the common sense model of selfregulation (CSM) as a theoretical framework, this thesis aimed to: 1) investigate the capacity of illness perceptions and coping strategies to predict patient and caregiver psychological outcomes, at diagnosis and again 6 months later, and 2) examine the effectiveness of a brief psychological intervention targeting illness perceptions and coping to improve patient HRQL, and patient and caregiver psychological wellbeing. Two studies were conducted to achieve these aims. First, an observational prospective study was implemented, in which patients and their caregivers completed questionnaires at HNC diagnosis and at 6 month follow-up. Second, a pilot randomised controlled trial (RCT) investigated psychological outcomes among patients and caregivers who received a self-regulatory intervention in addition to standard care compared to those who received standard care alone. Study 1 found that patient and caregiver illness perceptions interacted to influence patient HRQL, cross-sectionally and over time. Patient HRQL was lowest when patients and their caregivers had dissimilar perceptions of HNC at diagnosis. Coping strategies were also found to predict patient psychological wellbeing. Patients who engaged in self-blame and avoidant coping at diagnosis reported lower HRQL and higher post-traumatic stress 6 months later. Similar findings were documented among caregivers, with negative perceptions regarding patient symptoms and treatment control, and use of avoidant coping strategies, related to higher subsequent post-traumatic stress. The results of Study 2 demonstrated that it was feasible to deliver a brief self-regulatory intervention to patients and caregivers early after HNC diagnosis and during treatment. The intervention was effective at improving patient perceptions of treatment control and social HRQL. In conclusion, the results of this thesis suggest that the CSM has applicability in patients with HNC and their caregivers. Both illness perceptions and coping explained variation in patient and caregiver psychological outcomes over time. Study 1 of this thesis is the first to investigate interactions between patient and caregiver illness perceptions longitudinally, and to demonstrate that illness perceptions and coping contribute to patient and caregiver post-traumatic stress. Study 2 is the first to show that a brief psychological intervention targeting illness perceptions and coping can be successfully delivered to patients soon after diagnosis and during treatment, and may be adapted to include caregivers. These results have important clinical implications, including identification of individuals with inaccurate perceptions of HNC and those engaging in maladaptive coping behaviours early in the disease trajectory, and the incorporation of self-regulatory interventions into standard HNC care. Future research could investigate the effectiveness of interventions targeted to patients experiencing distress to determine whether further benefits in psychological wellbeing may be achieved. Research into psychological interventions that may alleviate the distress of HNC caregivers is also needed.