Personality Associations with Mood, Hoarding, Health and Well-being Janet Katherine Spittlehouse A thesis submitted for the degree of Doctor of Philosophy Department of Psychological Medicine University of Otago, Christchurch New Zealand 31 August 2016 Abstract Background: Personality has been of interest since ancient times. Hippocrates, also known as ‘The father of Western Medicine’ was possibly the first to document the association between personality and mental and physical health by describing the ancient medical theory of Humourism. Over the last 100 years the study of personality has been evolving and there are many different perspectives. Trait perspectives have become popular but they lack any underlying theory about how personality develops. Psychobiological models offer descriptions of personality and provide testable theories on how biology influences their development. A robust psychobiological model is Cloninger’s psychobiological theory and it provided the basis for this project. Objectives: This project explored the associations of personality in different mental health settings using the Temperament and Character Inventory (TCI; Cloninger, Przybeck, Svrakic, & Wetzel, 1994), the personality inventory developed by Cloninger and colleagues, that is suitable for measuring both normal and abnormal personality. The TCI was used to examine the impact of depression on personality measurement and personality associations to self-reported physical and mental health, mood disorders, hoarding behaviours and well-being. Methods: Participants for this project were from three studies. Two randomised clinical trials designed to examine predictors of treatment response for depressed outpatients using either antidepressant medication (N=195) or psychotherapy (N=177) were used to examine the impact of depression on measures of personality. Data from the Canterbury Health, Ageing and Lifecourse (CHALICE) study (N=404), a random community sample of 50 year olds taking ii part in an observational study of ageing, were used to examine personality in relation to self- reported health, lifetime mood disorders, hoarding behaviours and well-being. Results: Harm avoidance and self-directedness were strongly associated with physical and mental health, mood disorders, hoarding behaviours and well-being. Both harm avoidance and self- directedness change with mood state. After adjusting for mood state, self-directedness but not harm avoidance was associated with risk of a lifetime mood disorder. High harm avoidance and low self-directedness were strongly associated with poorer self-reported mental and physical health and increased hoarding behaviours. Hoarding disorder was strongly associated with economic hardship and impairment of mental and physical functioning. For well-being, low harm avoidance and high self-directedness were associated with better well-being and these two variables explain more of the variance in well-being than other measures such as socio-demographics. The TCI personality variables of novelty seeking and self-transcendence were associated with specific psychopathology while reward dependence, persistence and cooperativeness had no or weak associations with different aspects of health and well-being. Conclusions: TCI variables of harm avoidance and self-directedness were fundamental to health and well- being, consistent with the wider literature. The finding that self-directedness, but not harm avoidance, was a risk factor for mood disorder, could possibly be explained by self- directedness becoming increasingly important with age. Despite the overwhelming effect of harm avoidance and self-directedness, there were significant if subtle personality differences in the other TCI variables that contributed to health and well-being and personality assessment of the individual may be helpful in determining cognitive and emotional style. If the Cloninger model of personality, which separates the neurobiology of temperament and iii character, is correct then self-directedness should be more amenable to change and so is a potential target for interventions to reduce psychopathology. iv Preface In 2008 I was employed as research coordinator for the CHALICE study and in 2009 as a research fellow. I enrolled as a part-time PhD candidate in 2009, examining questions related to personality, mood and well-being. Whilst the CHALICE study was recruiting I focused on data from two studies of depression previously conducted in this department. My role in the CHALICE study encompassed all aspects of the day-to-day management of the study including: liaising with the principal investigator to prepare and finalise assessments and data collection instruments, recruiting and supervising interviewers for the study, overseeing the recruitment of participants and data collection, conducting a comprehensive (5-6 hour) assessment of participants, ensuring appropriate feedback of results was provided to participants, assisting with the preparation of research grants and ethics applications, writing and submitting papers for publication in peer reviewed scientific journals and conference proceedings. CHALICE participants were recruited and assessed at a time of considerable earthquake activity in the Canterbury region which will be described in the first results chapter (Chapter 5). The CHALICE study was supported by grants awarded from Lottery Health, Canterbury Community Trust and University of Otago Foundation research grant. Professor Peter Joyce was the principal investigator and the other investigators were: Vicky Cameron, Steve Chambers, Richard Gearry, Hamish Jamieson, Martin Kennedy, Cameron Lacey, David Murdoch, John Pearson, Richard Porter, Mark Richards, Philip Schluter and Richard Troughton. v Acknowledgements Thank you to all the participants who took part in the three studies described in this thesis. Without their willingness and commitment this research would not have been possible. Thank you to my supervisors Professor Peter Joyce, Dr Esther Vierck and Dr John Pearson for their guidance, patience and wisdom. To my partner, Dr Sandy Slow, thank you for your love, loyalty and support. Thank you to all those who worked on the CHALICE study and on the two clinical trials of depression; to Monica Johnstone and Andrea Bartram for data management, to Dr Esther Vierck, Dr Anna Thorpe, Julia Martin, Bridget Kimber and Robyn Abbott for participant assessments and to Wendy Sincock for preparation of this thesis. To all my family and friends here in New Zealand and the United Kingdom, thank you for your encouragement, love and humour. I dedicate this thesis to my late mother Judith Patricia Spittlehouse (1935 – 2016). vi List of Publications I have three first author and one second author publications related to this thesis. Publications directly related to this thesis: Spittlehouse, J. K., Joyce, P. R., Vierck, E., Schluter, P. J., & Pearson, J. F. (2014). Ongoing adverse mental health impact of the earthquake sequence in Christchurch, New Zealand. Australian and New Zealand Journal of Psychiatry, 48(8), 756-763. doi:10.1177/0004867414527522. (Appendix A) Spittlehouse, J. K., Pearson, J. F., Luty, S. E., Mulder, R. T., Carter, J. D., McKenzie, J. M., & Joyce, P. R. (2010). Measures of temperament and character are differentially impacted on by depression severity. Journal of Affective Disorders, 126(1-2), 140-146. doi:10.1016/j.jad.2010.03.010. (Appendix B) Spittlehouse, J. K., Vierck, E., Pearson, J. F., & Joyce, P. R. (2014). Temperament and character as determinants of well-being. Comprehensive Psychiatry, 55(7), 1679-1687. doi:10.1016/j.comppsych.2014.06.011. (Appendix C) Publications related to this thesis: Schluter, P. J., Spittlehouse, J. K., Cameron, V. A., Chambers, S., Gearry, R., Jamieson, H. A., . Joyce, P. R. (2013). Canterbury Health, Ageing and Life Course (CHALICE) study: rationale, design and methodology. New Zealand Medical Journal, 126(1375), 71-85. (Appendix D) vii Table of Contents Abstract ........................................................................................................................... ii Preface ............................................................................................................................ v Acknowledgements ....................................................................................................... vi List of Publications ....................................................................................................... vii Table of Contents ........................................................................................................ viii List of Tables ................................................................................................................. xix List of Figures ................................................................................................................ xxi List of Appendices ....................................................................................................... xxii List of Abbreviations .................................................................................................. xxiii Part 1: Introduction ................................................................................. 1 Chapter 1: Introduction .......................................................................... 1 1.1 Introduction ...................................................................................................... 1 1.2 Context of this Research ..................................................................................