Exploring the relationship between persecutory ideation and subjective wellbeing

Subjective wellbeing (SWB) refers to an individual's perception of their psychological, emotional and social wellbeing (Keyes, 2002). Persecutory ideation refers to thoughts that an individual will come to harm due to the deliberate intention of other people (Freeman & Garety, 2000). These thoughts are common in the general population. Persecutory ideation has been found to be experienced by up to 18.6% of people per year (Freeman et al., 2011). Persecutory delusions are experienced by 90% of people experiencing first episode psychosis (Moutoussis, Williams, Dayan & Bentall, 2007) and have been associated with distress and poorer clinical outcomes (Freeman, 2016). Several theories of the development and maintenance of persecutory ideation have been proposed. Social factors such as insecure attachment, neglect and physical abuse have been found to be associated with persecutory ideation in clinical and non-clinical samples (Bentall, Wickham, Shevlin & Varese, 2012; Pickering, Simpson & Bentall, 2008; Sitko, Bentall, Shevlin & Sellwood, 2014). Cognitive mechanisms have also been found to be associated with persecutory ideation, including reasoning biases (Garety & Freeman, 1999) and worry (Freeman et al., 2012). The overarching aim of the present thesis is to provide a thorough review and empirical investigation of the complex relationship between persecutory ideation and SWB. Chapter one: The first chapter of this thesis is a systematic review that aimed to investigate the relationship between persecutory ideation and SWB. Due to the variation in terminology used within the literature, studies investigating the relationship between persecutory ideation and the related concept of quality of life (QoL) are also included in the review. In particular, the review sought to answer whether people with higher levels of persecutory ideation have lower levels of SWB. Additionally, it considered whether the relationship between persecutory ideation and both SWB and QoL differs between people whose persecutory ideation is classified as "delusional" and those with lower levels of persecutory ideation. Lastly, it sought to identify variables that influence this relationship. Overall, a moderate negative correlation was found between persecutory ideation and both SWB and QoL, in people with and without a history of mental health difficulties. There was some evidence that this relationship may be stronger in people experiencing non-clinical levels of persecutory ideation, compared to individuals experiencing psychosis. A dearth of literature investigating psychological mechanisms that influence the relationship between persecutory ideation and SWB or QoL was found. Chapter two: The second chapter of this thesis is an empirical paper that aimed to investigate the psychological factors that influence the relationship between persecutory ideation and SWB in the general population. It considered the role of persecution deservedness (believing that perceived persecution is deserved), cognitive fusion (being entangled with one's thoughts and believing them as fact) and sense of coherence (feeling one's environment is understandable, manageable and meaningful) in this relationship. A new conceptual model of these factors was proposed and tested. A negative relationship between persecutory ideation and SWB was found. Sense of coherence was found to predict SWB, beyond the level of persecutory ideation. Additionally, people who have accessed mental health services had higher levels of persecutory ideation and lower levels of SWB than people with no history of mental health difficulties. No significant interaction effects were found and therefore the findings did not support the proposed conceptual model. Overall conclusions: There is strong evidence that there is a negative relationship between persecutory ideation and both SWB and QoL, in both clinical and non-clinical samples. It may be beneficial to consider specific psychological interventions to reduce persecutory ideation in people accessing mental health services, regardless of their diagnosis. Wider interventions could be considered to improve SWB and QoL related to persecutory ideation in the general population. These may target experiences and mechanisms that have been found to be associated with the development of persecutory ideation. Further research is needed to investigate other psychological factors that may influence the relationship between persecutory ideation and both SWB and QoL. Sense of coherence is one factor that has been found to be related to SWB, so may be helpful to consider when providing psychological interventions to individuals experiencing persecutory ideation.