EN FRANCIA

3.5.1 Gender Issues

Based on the literature, in order for cancer patients to change their lifestyle they need information, social support and appropriate healthcare guidance while several psychological constructs are related to changes in lifestyle (HRQOL, control, perceived causes of disease). Furthermore, even though men are more likely to adhere to risky behaviours (Courtenay, 2000; Oksuzyan et al., 2008), no studies have investigated the determinants of post-diagnosis health behaviour changes in men only. The challenge to identify what makes men change their health behaviours after diagnosis is evident in studies that have shown that men are less likely to change or maintain their health behaviour (Patterson et al., 2003; Demark-Whanefried et el., 2005; Mosher et al., 2009).

On the other hand, studies of women with breast cancer (Patterson et al., 2003; Salminen

et al., 2004; Salminen et al., 2000; Maunsell et al., 2002) found that 30%-48% of women

change their diet after diagnosis. The proportion of these changes for prostate cancer

patients, what dictates them and how they make sense of them is still unknown.

Similarly, evidence by Pinto, Eakin and Maruyama (2000), who conducted a systematic review on dietary intake interventions after cancer diagnosis, found that until 2000 there were four studies involving dietary interventions for cancer patients (Nordevang et al., 1992; Chlebowski et al., 1993; Pierce et al., 1997; Kristal et al., 1997). These studies recruited only breast cancer patients and looked at whether members of this population modified their dietary behaviour after diagnosis, during and after treatment. They also looked at the effect these changes have on survival and recurrence but none looked at the effect of these changes on bio-behavioural outcomes, HRQOL, physical functioning, etc.

3.5.2 Dietary Change

Thus there is a big gap in the literature for two reasons. Firstly, until 2000 no study existed that investigated the effect that dietary behaviour change has on psychological and bio-behavioural outcomes, such as aspects of HRQOL, physical functioning, etc., or which psychosocial constructs have an effect on prostate cancer patients’ dietary changes post-diagnosis.Also, no similar systematic review has been carried out since then. At the same time, even though a systematic review had identified studies that focused on the psychosocial outcomes of exercise change among breast cancer patients (McNeely et al., 2006), after 2000 the studies that elaborated on dietary changes after cancer diagnosis suffered from limited evidence on causal relationships (Blanchard et al., 2003; Demark-Wahnefried et al., 2004; Mosher et al., 2009). Secondly, the majority of these studies investigated breast cancer patients while only a few studies focused on the effect of dietary changes on prostate cancer patients’ HRQOL (Mosher et al., 2009;

Daubenmeier et al., 2006; Demark-Wahnefried et al., 2006; Morey et al., 2009;

Blanchard et al., 2008; Demark-Wahnefried et al., 2004; Blanchard et al., 2004).

McGinnis et al. (2002) indicate that approximately half of annual deaths in the USA can

be explained by unhealthy behaviours. Even though similar reports are not available for

Europe and the UK it can be postulated that similar trends exist in the UK. A review

previously (Andersen, 1994) suggests that interventions will be more effective if

psychosocial interventions include health behaviour components. The review suggests that HRQOL along with health-protective and health-promoting behaviours may affect survivorship as well.

Evidence from a systematic review regarding the role of lifestyle changes in managing diabetes is compelling (Gillies et al., 2007). It found lifestyle changes to be equally important to managing Type 2 diabetes as drug treatment. Even more so, maintaining changed lifestyle behaviour is even harder, with another systematic review (Curioni and Lurenco, 2005) indicating that 50% of people on a diet regain their lost weight after a year.

3.5.3 Information Needs

The time during which patients develop their information needs after diagnosis has yet to be clarified. There is inconclusive evidence indicating that patients develop their needs closer to diagnosis (Noh et al., 2009) while others argue that the needs develop in time as the diagnosis develops (Salminen et al., 2004; Friis et al., 2003). At the same time, the role of health care providers and significant others in patients’ adaptation is significant but underexplored. For example, there are no studies in the literature comparing significant others’ information needs with those of patients even though they constitute a population at risk of developing depressive symptoms after their significant others’ diagnosis (Couper et a., 2006; Street et al., 2010). Health care providers’

perceptions of patients’ needs are also important in optimizing patients’ health care provision and meeting patients’ needs.

The Centre for Disease Control and Prevention (CDC) and the Lance Armstrong

Foundation (LAF) have urged public health agencies to focus on providing access to

resources available and to focus on the importance of health education in strategies

aiming to improve health through multiple stages of cancer survivorship (Hawkins et al.,

2010). This Thesis builds on the understanding of the psychosocial processes, which

occur in prostate cancer patients after diagnosis and which are related to lifestyle changes focusing on diet.

The clinical importance of focusing on the processes that can have an impact on prostate cancer patients’ dietary changes post-diagnosis is to provide evidence for future interventions focusing on this cancer population. Blanchard et al. (2008) highlight the importance of designing intervention programmes that aim at healthier lifestyles among cancer survivors by indicating that these groups may benefit because of reports of suboptimal dietary behaviours. Findings on these processes can answer the question of what makes prostate cancer patients change their diets and inform future interventions aiming at promoting healthier lifestyles among this particular cancer population.

3.5.4 Social and Medical Support

In addition, the existing literature on health behaviours after cancer diagnosis including

diet is not without its limitations. Intervention studies often use multi-faceted

interventions, making it difficult to identify the effect of dietary changes while

intervention studies, which aim at changing diet, lack theoretical integration. The role of

healthcare providers in delivering the interventions is underutilized (Pinto and Trunzo,

2005). There is also minimal evidence in the literature on cancer patients’ readiness to

adhere to changes in their health behaviour especially bearing in mind evidence that

prostate cancer diagnosis interrupts couple’s relationships and their HRQOL (Galbraith

et al., 2011).

3.5.5 A Model of the Psychosocial Processes Post-Cancer Diagnosis

The evidence of loss of personal control due to cancer diagnosis (Eyre et al., 2001;

Patterson et al., 2003) and the coping mechanisms that are used to regain control, provide the need to establish a model to understand the psychosocial processes taking place on prostate cancer patients post-diagnosis (Figure 3.3). It has been established (see section 3.2) that patients make efforts to understand their condition by acquiring information, seeking support and comfort from their significant others and health care professionals and by changing their health behaviours.

Figure 3.3: A Model of Psychosocial Processes after Cancer Diagnosis

Cancer Diagnosis

Loss of Control

Coping Process

Health Behaviour

Change

Information Seeking Social

Support Seeking Medical

Support Seeking

Psychological Health Gender

Physical Health Illness Perceptions

There are also gender issues that are common for prostate cancer patients and which can influence patients’ coping process whereas the physical and psychological health of patients may also moderate the coping process. This Thesis will use this Model of Psychosocial Processes after Prostate Cancer Diagnosis, evidence from the literature and health behaviour theories and findings from the empirical Chapters to reach its objective.

Based on this Model, the aims of the Thesis are to:

 Investigate the information needs of patients and their significant others as a result of prostate cancer diagnosis, their predictors and the time these needs are developed (Chapter 4)

 Compare the time of patients and significant others’ information needs development with GPs’ perceptions, exploring their predictors (Chapter 5)

 Systematically review the literature for evidence of an association between health (physical-psychological) and dietary behaviour change (Chapter 6)

 Investigate the predictors of dietary behaviour change after diagnosis and after therapy (Chapter 7)

 Explore patients’ underlying mechanisms of dietary behaviour changes after diagnosis (Chapter 8)

The previous three Chapters have established the Theoretical (Chapter 2) and

Methodological (Chapter 1) context of the Thesis while previous research and gaps in

knowledge have now been examined (Chapter 3). The following Chapters will attempt

to answer the Research aims of the Thesis.

Chapter 4:Study 1: Investigating prerequisites of