Circadian Factors in Coping with Chronic Stress

Transcription

1 Circadian Factors in Coping with Chronic Stress by Daniela Bellicoso A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Department of Psychology University of Toronto Copyright by Daniela Bellicoso 2017

2 Circadian Factors in Coping with Chronic Stress Daniela Bellicoso Doctor of Philosophy Department of Psychology University of Toronto 2017 Abstract Circadian rhythms, cyclic changes that repeat approximately once every 24 hours, regulate daily temporal processes of physiology and behaviour in all living organisms. Rhythmicity is adaptive, providing advantages for survival, growth, and reproduction. For human beings, this includes rhythmic regulation of mental, physical, and emotional responses to stressors. In this dissertation, we addressed how human beings facing major stressors such as chronic disease (in this case, cancer), are influenced by circadian timing, specifically chronotype and sleep quality. A broad epidemiological study was conducted among individuals in different roles (patients, medical staff, and familial caregivers) facing a common stressor to assesses their ability to cope with the situation. Breast cancer patients provided real-time reports of their coping across the day. Patients and familial caregivers completed retrospective average ratings for their coping across the day across treatment, along with details on use of coping behaviours. Oncology staff provided ratings of their burnout, and Professional Quality of Life (ProQoL). These data were all assessed in relation to chronotype and sleep quality, and to an extent, in relation to personality. Chronotype and sleep quality influenced coping within each group, but their impacts were not correlated. Nonetheless, working at chronotypically optimal times improved ProQoL. In the moment coping ratings from patients reflected their chronotype, as did their recalled coping. Openness was positively linked with ProQoL among staff, and with an engagement coping ii

3 style among patients and caregivers. The data reflect an influence of circadian timing on the expression of coping responses during chronic stress. A better understanding of changes in coping ability as they relate to one s innate rhythms will allow for the development of a cognitive and emotion-based chronotherapy regime intended to maximize proactive coping among individuals facing chronic stress, such as providing care or undergoing treatment for cancer. iii

4 Acknowledgments Without the help of the following people, this PhD would not have been possible I owe each of you many thanks for the kindness you showed me. My Primary Supervisor, Dr. Martin Ralph: Thank you for taking a chance on me and allowing me to begin conducting research in your lab as an undergraduate student, over 10 years ago. Your guidance, patience, and kindness through the years have allowed me the freedom to explore my own ideas and grow as a researcher in my own way. Thank you ever so much. Dr. Marg Fitch: Thank you for lending your expertise in the field of coping and adaptation to illness. Your invaluable guidance on how to approach the various topics explored in this research are greatly appreciated. It was a pleasure to work with you, and get to know you over the years. Dr. Maureen Trudeau: There are no words to express my gratitude for the guidance, kindness, and support you ve shown me. Without you, this research would not have been possible. It was a pleasure to learn from you. Thank you for the innumerable and invaluable opportunities for research, learning, and personal growth that you provided. The kind staff at Sunnybrook Hospital Odette Cancer Centre & Princess Margaret Hospital: Thank you for taking the time out of your busy schedules to offer suggestions on topics and questions for research, and to identify participants for my studies. Your participation in my studies and taking the time to sharing some of your own struggles relating to facing chronic stress were invaluable. I hope that my research, even if only in a small way, helps to make your job slightly more manageable. The Breast Cancer Patients and their Caregivers: Your willingness to partake in research, without any personal reward during your most difficult days is a testament to the good nature and kind spirit you each possess. Thank you for taking the time to chat with me, share your stories, and open-up to a stranger about some of your own daily struggles. Thank you for your selflessness. My husband Matthew, and my sister Elisa: You ve both given me courage in so many ways. The love and encouragement you both provided were invaluable, and greatly appreciated. iv

5 My grandparents, who came to this wonderful country over 60 years ago, in search of a better life for their families: The life lessons of hard work and determination that you each taught me helped me to achieve this degree. Thank you for the sacrifices you made, so I could have so many opportunities and such a wonderful education. And finally, my parents: You each instilled a love of learning, and a strong work ethic from early on in my life. You have been my biggest cheerleaders, never failing to give encouragement, and let me know how much you believed in me. The experiences and opportunities you provided from early on opened my eyes to so many things around me, and piqued my curiosity to always learn more and understand why things are a certain way. While you ve always told me how proud I make you, I m proud to be the daughter of two such wonderful people who allowed me to explore, to be me, and to make my own path in the world. v

6 Table of Contents Acknowledgments... iv Table of Contents... vi List of Tables... xi List of Figures... xiv Chapter General Introduction Context, Hypotheses, and Rationale Coping and Survival Strategies Coping Brief-COPE Questionnaire Circadian Rhythms and Coping Strategies Sleep and Coping Depression, Stress, and Coping Burnout, Stress, and Coping in Caregivers Personality and Coping Cancer as a Chronic Stress Emotional Distress in Patients Why Choose Breast Cancer Patients Specific Distress Involving Genetic Issues Emotional Distress in Caregivers Specific Distress Involving Partners Specific Distress Involving Oncology Staff Rhythmicity Biological Clocks in Nature Biological Clocks in Mammals Biological Clocks in Human Beings Cognition, Emotion, and Circadian Rhythms Chronotype Genetic Basis of Chronotype Questionnaires...19 vi

7 Performance Variances Emotionality Sleep Two-Process Model of Sleep The Functions of Sleep The Impact of Sleep and Sleep Loss Sleep, Cognition, and Memory Polysomnography and Actigraphy Sleep Quality Cancer Breast Cancer Patients Caregivers Oncology Staff Breast Cancer Background Cancer Biology Breast Cancer Biology Genetics and Mutations Incidence Diagnosis and Treatment Staging Procedures Other Tumour Characteristics Treatment Localized Systemic Prognosis...39 Chapter General Methods Procedures Nursing Study Hospital Staff Patients and Caregivers Instruments General Questionnaires Group Specific Questionnaires Nursing Staff...42 vii

8 Oncology Staff Patients and Caregivers Questionnaire Package Statistics...45 Chapter Burnout Among Oncology Nurses: Influence of Chronotype and Sleep Quality Abstract Introduction Materials and Methods Participants Procedure Measures Statistical Analysis Results Discussion Limitations Conclusions...65 Chapter Chronobiological Factors for Compassion Satisfaction and Fatigue Among Ambulatory Oncology Caregivers Abstract Introduction Materials and Methods Participants and Procedures Measures Statistical Analysis Results Descriptive Group Statistics Correlation Analysis Discussion Chronotype and ProQoL Sleep and ProQoL Personality and ProQoL Agreeableness...82 viii

9 Emotional Stability Openness Conscientiousness and Extraversion Job Satisfaction and ProQoL Limitations Conclusion...86 Chapter Primary Circadian Impacts on Patients, Caregivers, and Dyads Abstract Introduction Materials and Methods Participants and Procedures Measures Statistical Analysis Results Descriptive Statistics Overall Demographic Comparisons Morningness-Eveningness Distribution Sleep Quality Comparison UTIME Performance Results Analysis 1: Total Patient Population Analysis Multifactorial Correlation Analysis Global Correlations Among Patients MEQ, PSQI and UTIME data Total Patient Population Mixed Measures ANOVAs Analysis 2: Total Caregiver Population Analysis Global Correlations Among Caregivers MEQ, PSQI and UTIME data Caregiver Population Mixed Measures ANOVAs Analysis 3: Matched Patient and Caregiver Population Analysis Global Associations and Differences Among Matched Patient and Caregiver MEQ, PSQI and UTIME data Matched Patient and Caregiver Group Mixed Measures ANOVAs Discussion On the Independent Impacts of Sleep and Chronotype Patient Cognitive Function and Emotional Regulation Chronotype-UTIME Correlations Multivariate Analysis of UTIME Correlations in the Patient Population ix

10 5.5.3 Caregiver Cognitive Function and Emotional Regulation Matched Patient and Caregiver Cognitive Function and Emotional Regulation Limitations Conclusion Chapter Coping Behaviour in Chronic Disease Abstract Introduction Materials and Methods Participants and Procedures Measures Statistics Results Discussion Personal Coping Assessment Coping Behaviours: Changes in Coping Scores In the Moment Coping vs. Coping Behaviours Limitations Conclusion Chapter Conclusion Chronotype Sleep Quality Personality Future Directions Bibliography x

11 List of Tables Table 3.1 Table 3.2 Table 3.3 Table 3.4a Table 3.4b Table 3.4c Demographic characteristics and questionnaire response ratings of participants.. 52 Comparison of burnout ratings between respondents with good and bad sleep quality and between MEQ types. 54 Analysis of bivariate correlations for participants questionnaire response ratings.. 56 Summary of hierarchical multivariate regression analysis for variables predicting personal burnout among oncology nurses (N = 64) Summary of hierarchical multivariate regression analysis for variables predicting work related burnout among oncology nurses (N = 64) Summary of hierarchical multivariate regression analysis for variables predicting client related burnout among oncology nurses (N = 64).. 60 Table 4.1 Table 4.2 Table 4.3 Table 4.4 Table S4.1 Table S4.2 Table S4.3 Means and frequencies of participant demographic and questionnaire data.. 72 Non-parametric correlations between ProQoL domains (columns) and covariates (rows).. 75 Final models in backwards multiple regression with professional quality of life (CS, BO, and STS) as dependent variables, and significant values* (as tested by univariate regression) for MEQ, PSQI, JSS and TIPI as independent variables. 77 Models in backwards multiple regression with professional quality of life (CS, BO, and STS) as dependent variables, and significant values* (as tested by univariate regression) for MEQ, PSQI, TIPI and working on multiple vs. single cancer sites as independent variables.. 79 Spearman correlations (r s ) between continuous variables, and point biserial correlations for categorical variables (demographics, chronotype and sleep quality). 88 Spearman correlations (r s ) between continuous variables, and point biserial correlations for categorical variables related to job satisfaction.. 89 Spearman correlations (r s ) between continuous variables, and point biserial correlations for categorical variables related to personality and professional quality of life xi

12 Table 5.1 Table 5.2 Table 5.3 Table 5.4 Table 5.5 Table 5.6 Table 5.7 Table 5.8 Means and frequencies of demographic and questionnaire data for patients and caregivers 99 Means and frequencies for chronotype and sleep quality questionnaires for patients and caregivers Spearman correlations for chronotype versus sleep quality and UTIME among patients Mixed ANOVAs on patient sleep quality and UTIME: main effects and interactions Spearman correlations for caregiver chronotype versus sleep quality and UTIME. 112 Mixed ANOVAs on caregiver sleep quality and UTIME: main effects and interactions Median and Mann Whitney U significance values comparing MEQ, PSQI, and UTIME response scores between patients and their caregivers Mixed ANOVAs on patient AND caregiver sleep quality and UTIME: main effects and interactions Table 6.1 Descriptive data for patient coping logs. 146 Table 6.2 Table 6.3 Table 6.4 Median and Friedman test data for changes in raw patient coping log scores across treatment, with Wilcoxon signed-rank tests with Bonferroni correction applied for differences in raw patient coping log scores across treatment. 148 Mean ± standard deviation and paired samples t-test data for preand post-chemotherapy coping rating comparisons Pearson correlations between MEQ and PSQI and patients coping log UTIME scores Table 6.5 Descriptive data for Brief COPE are mean ± standard deviation Table 6.6a Table 6.6b Table 6.7 Table 6.8 Median and Friedman test data for changes in Brief COPE scores across treatment among patients and caregivers. 157 Wilcoxon signed-rank tests with Bonferroni correction applied for differences in Brief COPE scores across treatment 158 Summary of Multiple Regression Analyses for Brief-COPE Scores Across Treatment, assessing the predictive value of participant role, chronotype, and sleep quality. 163 Descriptive data and independent samples t-test for BFAS between men and women. Descriptive data are mean ± standard deviation, for patients and caregivers xii

13 Table 6.9 Summary of Multiple Regression Analyses for Brief-COPE Scores Across Treatment, assessing the predictive value of participant role, chronotype, sleep quality and personality xiii

14 List of Figures Figure 5.1a UTIME scores across treatment for the total patient group 101 Figure 5.1b UTIME scores across treatment for patients without a caregiver involved in the study Figure 5.1c UTIME scores across treatment for patients with a caregiver involved in the study Figure 5.1d UTIME scores across treatment for caregivers xiv

15 Chapter 1!! General Introduction 1.1! Context, Hypotheses, and Rationale Circadian rhythms, cyclic changes that repeat approximately once every 24 hours, regulate daily temporal processes of biology and physiology in all living organisms. Rhythmicity is expressed in processes at all levels of biological organization. At a molecular level, cell division and replication are known to be rhythmic. At a higher level, cognition, physical functioning, and emotionality have all been linked to a rhythmic preference for morning (M) versus evening (E) performance, known as chronotype. Our biology, physiology, and behaviour are governed by clocks. In this same vein, previous studies have explored the impact of rhythmicity on various domains of health. Different findings in areas such as cardiology (e.g., Portaluppi et al., 2012), musco-skeletal function (e.g., Riley & Esser, 2017), gynecology/obstetrics (e.g., Dogru et al., 2016), and mental health (e.g., Hasler, Allen, Sbarra, Bootzin, & Bernert, 2010) support evidence for health and rhythms. Coping strategies, specifically, coping with chronic trauma that accompany health issues, has not been examined in depth in relation to rhythmicity. Very little is known about how human beings might respond at different times of day to a major stressor such as chronic disease, along with other environmental factors that will influence an individual s behaviour. This dissertation focuses on how human beings facing major stressors (specifically, chronic disease) are influenced by circadian timing. Based on existing information on rhythmicity of emotional responses (e.g., Costa-Martins et al., 2016; Lenaert, Barry, Schruers, Vervliet, & Hermans, 2016), a person s ability to cope with not only the chronic disease but the other stressors in their environment might vary according to the timing of their circadian cycle. Given that research has suggested that how an individual deals with their disease or stressors can impact outcome (e.g., Demytteraera et al., 1998; Shehmar & Gupta, 2010) it is important to understand if and how these abilities might vary through the day. Furthermore, stress can contribute to perpetuating a disease and disrupting circadian rhythms (McEwen & Karatsoreos, 2015). We should recognize that if this is the case, then not only will patients be affected, but 1

16 2 also everyone involved with the patient and going through the highly stressful situation will also be influenced. It is reasonable to predict that the stress that occurs due to the disease itself, together with the stresses felt by patients and caregivers will have a mix of influence on coping. We initiated a large scale epidemiological study of a group of individuals facing the same stressor (cancer), but each in a different role (patient, medical staff, familial caregiver), looking at their ability to cope with the situation. We examined a number of important variables believed to influence coping behaviour and memory for coping, by conducting various cross-sectional and longitudinal studies. Using surveys and data logs, we collected measures of participants chronotype, sleep quality, personality, and coping. To examine chronotype and sleep quality, this requires an understanding of the rhythmic processes, starting with the generation of rhythms by biological clocks, and the expression of that timing in the regulation of behaviour. It requires also an understanding of the individual and the disease itself. It also involves an understanding of sleep stages and implications for good versus poor quality sleep. We narrowed down the focus to address a group of breast cancer patients where the disease itself is relatively well defined, as is treatment for the disease. The prognosis is also relatively well defined. Given that circadian rhythms influence cognitive function and emotional regulation throughout the day in the general population, (e.g., Blatter & Cajochen, 2006; Ottoni, Antoniolli & Lara, 2012) it is important to understand how these rhythms fluctuate among both cancer patients and caregivers faced with a chronic daily stressor such as cancer. While it is understood that disturbed rhythms can perpetuate poor health, less is known in general about circadian rhythms and emotionality and emotional responding, including behaviour and memory for behaviour. An understanding of emotionality and rhythmicity is required. It was hypothesized that rhythmicity would impact individuals responses to chronic stress, but the influence of circadian rhythms would vary depending on one s role, and whether coping ratings were retrospective or in the moment. A better understanding and documentation of changes in coping ability as they relate to one s innate rhythms will allow for the development of a cognitive and emotion-based chronotherapy regime intended to maximize proactive coping among cancer patients and their caregivers, both in the hospital and the home.

17 3 1.2! Coping and Survival Strategies 1.2.1! Coping Coping refers to those constantly changing cognitive and behavioral efforts to manage specific external and internal demands that are appraised as taxing or exceeding the resources of the person (Lazarus & Folkman, 1984, p. 141). These taxing demands that exceed one s personal resources are known as stress. Stress is a real or perceived interruption to the homeostasis of one s physical state or mental well-being. Stress can result from a range of positive and negative demands. For example, the stress of organizing a large event, or the physical stress that comes from exercise both have the potential to exceed one s mental or physical resources, respectively, to deal with the situation. However, the body s response to these self-sought out tasks can mimic the stress response seen when responding to a negative stressor (National Research Council, 2008). Individuals are each taxed differently by various demands, and will not necessarily respond the same way to a particular stressor. The individual efforts people perform to cope with stress affects their physical, psychological, and social well-being (Folkman & Lazarus, 1980). As such, it is important to understand how a specific stressor can elicit various coping responses from different individuals, and the effect these efforts will have on well-being ! Brief-COPE Questionnaire The cognitive and behavioural efforts an individual may use to cope or deal with the stress of a situation can range from healthy to negative, yet it can be difficult to clearly distinguish which specific efforts fall into either category. The Ways of Coping Questionnaire, developed by Folkman and Lazarus (1980), suggests certain efforts can be categorized into problem or emotion focused coping styles. Problem focused coping strategies are intended for problem solving or performing some action to change the source of the stress. Emotion focused coping efforts are intended to manage or reduce the emotional distress being created by or associated with the stressor. It is important to note that of the two techniques, neither is necessarily more or less positive or negative than the other. This distinction between problem and emotion focused coping is very basic, and it is important to note that not all efforts aimed at reducing a stressor necessarily fall neatly into one category or the other (Carver, Scheier, & Weintraub, 1989).

18 4 The COPE is a 60-item, 15-scale measure, and contains many items which can be considered as either emotion or problem focused coping. The COPE was also found to be correlated in varying degrees to certain personality traits. Findings demonstrated that functional coping strategies are generally linked to personality traits from various questionnaires that are seen as beneficial, while less functional coping strategies showed inverse correlations with desirable personality traits. The COPE was designed to address three key issues the authors believed existed with previous coping measures: 1.! Provide a more complete and comprehensive assessment of the various coping efforts people may engage in to deal with a stressor 2.! Reduce ambiguity and produce questions with a direct focus 3.! Develop a scale that is theoretically rather than empirically based, focusing on specific theoretical arguments that assess functional properties of coping strategies (Austenfeld & Stanton, 2004; Carver, Scheier, & Weintraub, 1989) This research assesses coping strategies using the Brief COPE, a 28-item 14-scale measure which is a condensed version of the original COPE questionnaire. The Brief COPE was created to:!!!! Minimize time demands on participants Revise the questionnaire to exclude two irrelevant scales Slightly refocus three scales Include a self-blame scale evidence that had since been proved was important The Brief COPE continues to address the three key goals of the original COPE. Like the original COPE, the Brief COPE continues to include both adaptive and dysfunctional measures of coping. The items of the Brief COPE can be presented in three formats:!!! Situational retrospective (e.g., I ve been doing things to try and take my mind off the situation ) Dispositional (e.g., I do things to try and take my mind off the situation ) Situational concurrent (e.g., I m doing things to try and take my mind off the situation ).

19 5 The 14 scales of the Brief COPE refer to coping in the following ways: 1.! Active Coping: taking measures to attempt to remove or avoid the stress, or ameliorate its effects 2.! Planning: coming up with strategies to deal with the stressor and best handle the situation 3.! Positive Reframing: managing or reframing distressing emotions resulting from the stressor or situation in positive terms 4.! Acceptance: accepting the reality of and attempting to deal with the situation or stressor; opposite of denial 5.! Humour: making fun of the stressor or situation in an attempt to make light of the situation 6.! Religion: using religion to provide a source of comfort, or to clear or organize one s thoughts about a stressor 7.! Using Emotional Support: seeking out moral support, sympathy, and or understanding from others about having to deal with the stressor or situation; this is emotion-focused coping 8.! Using Instrumental Support: getting advice, assistance, and or information from others on how to deal with the stressor or situation; this is strictly problem-focused coping 9.! Self-Distraction: focusing away from the stress; intentionally performing activities to take one s mind off the stressor 10.!Denial: attempting to push away or ignore the reality of the situation; opposite of acceptance 11.!Venting: focusing on the stress 12.!Substance Use: using alcohol or drugs to think less about the stressor 13.!Behavioural Disengagement: lessening or giving up one s attempts to deal with the stressor and/or achieve goals the stressor interferes with 14.!Self-Blame: criticizing oneself as being responsible for the stressor or situation Certain scales of the Brief COPE are clearly dysfunctional or adaptive, or carry a distinct negative or positive tone. For example, behavioural disengagement is clearly negative as it involves one giving up any attempt of working with the situation or stressor. Conversely, acceptance carries a strong positive tone as it requires one come to terms with the stressor, which creates opportunity to move forward and deal with the stresses one is facing. Yet other categories

20 6 are less clearly defined on whether they are adaptive or dysfunctional coping strategies. For example, humour can be used to shed light on the situation and possibly make it easier to face a stressor, however, this can also become dysfunctional if someone uses humour to not have to face the severity of a stressor or situation. It is important to keep the nature of each scale in mind when assessing the various coping strategies used by patients. Furthermore, it is important to assess if certain coping styles as indicated by particular scales tend to co-occur (Carver, 1997) ! Circadian Rhythms and Coping Strategies While the literature focusing specifically on circadian rhythms and coping is sparse, research does indicate that the cognitive and emotional processes which regulate one s use of particular coping strategies are under circadian control. Functioning of cognitive and emotional processes vary over the course of the 24 h day. An appropriately timed wake and sleep cycle that reflects one s internal biological clock facilitates maximal cognitive and emotional performance. Conversely, a wake sleep schedule that does not mirror one s biological clock can reduce an individual s cognitive and or emotional regulatory abilities (Wright, Lowry, & LeBourgeois, 2012). Given that the use or disuse of cognitive, emotional, and or inhibitory control in different combinations plays a role in each of the coping strategies people commonly use (i.e., such as those assessed in the Brief COPE), these dimensions provide an important link between circadian rhythms and the coping strategies an individual may use. Circadian oscillators are known to regulate cognition based functions, such as maintaining alertness, and learning and memory formation and recall. Performance of these cognitive functions is significantly reduced when occurring out of synchrony with one s innate circadian rhythm, such as at one s off peak time as indicated by their chronotype (Krishnan & Lyons, 2015). One s inhibitory control is also modulated by chronotype. For example, on a task measuring vigilance, M type individuals maintained high performance when tested in the morning, whereas their performance decreased with time on task in the evening. Conversely, E type individuals showed worse inhibitory control with greater time on task in the morning session and greater performance in the evening testing session (Lara, Madrid & Correa, 2014). This study indicates that for cognitive measures, the negative effects of time on task can be mediated by testing an individual at his or her chronotypically optimal time in accordance with their circadian rhythm. Inhibitory control is

21 7 particularly important to coping as it may allow for blocking certain coping strategies that may be negative or dysfunctional, and that an individual may be aware are not in their best interest, but may be a natural response. At one s chronotypically optimal time, it may be easier to work to actively avoid particular unwanted strategies, whereas at one s off peak times, inhibitory control may be lacking and subsequently facilitate the use of these otherwise blocked out strategies. In addition to changes in cognitive regulatory abilities across the day in line with one s circadian rhythm, it appears that chronotype is also linked with changes in emotionality and mood. When measuring affect across the day for an entire week in healthy individuals, M type individuals showed the quickest rise in positive affect in the morning between 9 a.m. and noon, followed by a dramatic decrease after 9 p.m. Conversely, N (neither type, i.e., intermediate between M and E types) and E types did not demonstrate the same rapid rise in positive affect in the morning as was seen among M types (Clark, Watson & Leeka, 1989). Among healthy individuals, depressive symptomatology is more common among E type individuals than M types, suggesting an E chronotype may be a predisposing factor for depression (Hidalgo et al., 2009). These results have been replicated even among individuals with different physical health levels. For example, between normal versus overweight females, E typology remains associated with a greater number of depressive symptoms (Pabst, Negriff, Dorn, Susman & Huang, 2009), suggesting E types report more depressive symptomatology regardless of physical health. Even among healthy individuals, one s innate rhythm may predispose an individual towards greater use of negative or dysfunctional coping strategies, and overall poorer stress management abilities ! Sleep and Coping Everyone copes differently. The coping strategies one uses will influence their life in various ways, including impacting their sleep quality. Cognitive arousal among healthy individuals dealing with stressful life events has been linked to sleep disruptions and or chronic insomnia (Friedman, Brooks, Bliwise, Yesavage & Wicks, 1995). It is believed that adequate sleep duration may act as a biobehavioural regulatory and restorative process that regulates one s daily emotional experiences and allostatic loads of emotional stress (Vandekerckhove & Cluydts, 2010). Among individuals with major depression, one s use of avoidance behaviours as a coping mechanism, along with the intrusion of unwanted thoughts are known to contribute to poor sleep (Hall et al., 1997). Among physically healthy persons, emotional arousal caused by anxiety is

22 8 also known to produce sleep disruptions, due in large part to activation of the corticotropinreleasing hormone system which is recruited for reacting to emotional stress and is believed to regulate spontaneous waking (Staner, 2003). Cancer patients and their caregivers both in the home and hospital are under cognitive and emotional strain. Cancer patients sleep is known to generally be poor. Among healthy individuals, sleep plays an important role in mediating coping as they face regular daily events. Therefore, it is important to assess sleep as a variable associated with changes in coping across the day in a cancer patient or caregiver s ability to face the various stresses involved in their role. Among early stage breast cancer patients, the use of avoidance coping has been linked with greater time needed to fall asleep across the treatment trajectory. Similar results have been found in men with prostate cancer, along with decreased sleep onset time (i.e., sleep latency) both at baseline and across treatment when approach coping strategies are used (Thomas, Bower, Hoyt & Sepah, 2010). In a study of a varied sample of men with cancer, use of avoidance coping at baseline was associated with poorer sleep at follow up testing. The authors suggested that using avoidance coping towards cancer-related stressors or circumstances is likely due to poorer mood and reduced sleep (Hoyt, Thomas, Epstein & Dirksen, 2009). In this case, it is possible that poorer mood creates greater emotional arousal, leading to subsequent sleep disruptions. Familial cancer patient caregivers report similar results. The use of less functional coping strategies (e.g., venting, self-distraction, self-blame) have been associated with increased sleep disruptions (Aslan, Sanisoglu, Akyol & Yetkin, 2009; Carter & Acton, 2006; Northouse, Williams, Given & McCorkle, 2012). Associations have also been found in some studies suggesting that the use of positive, proactive coping strategies among caregivers has been associated with reduced numbers of sleep disturbances (Zhang, Yao, Yang, & Zhou, 2014). Interestingly, in studies among patients and caregivers, while research seems to consistently point to a positive correlation between less functional coping styles and increased reports of poor sleep, not all studies seem to find this association between functional or proactive coping strategies and better sleep quality. Research on the association between sleep quality and coping strategies required to face the stresses of being an oncology staff member (e.g., oncologist, oncology nurse, etc.) is more scarce. Given the cognitive and emotional burden of caring for cancer patients both treatable and terminal it is important to have well developed, functional coping strategies. In a study of nurses following a shiftwork schedule, on average, sleep quality was found to be poor, as rated

23 9 by the PSQI. Among this same sample, high emotional disturbance was correlated with poorer overall sleep quality and greater sleep disturbances (Lee, Chen, Tseng, Lee & Huang, 2015). While no actual coping measure was used in this study, the high level of emotional disturbance suggests a lack of coping strategies being used to mediate the emotional demands of the job. While ambulatory oncology staff do not all follow shiftwork schedules, there are still several cognitive and emotional demands to be dealt with on a daily basis that require well developed functional, proactive coping strategies. While the current literature indicates that sleep and coping are related, it is important to understand how sleep may be associated with one s perceived coping abilities as they change across the day. A better understanding of the influence of sleep on various coping strategies will guide the development of strategies to teach necessary healthy coping behaviours to patients and caregivers to better help them in their role. A better understanding of changes in coping across the day as they relate to one s sleep quality will allow for necessary assistance to be provided at times of day when additional help may be required to cope in a proactive fashion ! Depression, Stress, and Coping In North America, major depressive disorder is the leading cause of disability, and by 2020 is projected to become the second leading cause of disability worldwide (Muscatell, Slavich, Monroe & Gotlib, 2009). Depression, which refers to a range of mental health problems, is characterized by persistent traits such as low mood state, little or no positive affect, and functional and social impairment. According to Radloff (1977) who designed the Centre for Epidemiological Studies Depression Scale (CES-D), key major components of depressive symptomatology include low mood, feelings of guilt and worthlessness, a sense of helplessness and hopelessness, little or no appetite, psychomotor retardation or delay, and sleep disturbances. Stress either chronic or acute can play a role in the development of depression (Hammen, Kim, Eberhart & Brennan, 2009; Muscatell, Slavich, Monroe & Gotlib, 2009). One s reaction to, or interpretation of a stressor influences the mental impact it has on the individual and affects the stressors contribution to depression onset. When faced with stressors, individuals who exhibit depression or a high number of depressive symptoms are more likely to use dysfunctional coping strategies based on avoidance and denial; healthy controls are more likely to use positive, adaptive coping strategies aimed at accepting the stressor and making plans to move forward

24 10 towards one s goals (Orzechowska, Zajaczkowska, Talarowska & Galecki, 2013). Given the high stress levels typically experienced by cancer patient and caregiver populations, it is necessary to understand how one s use of specific coping strategies can reflect depression onset; such an understanding would allow treatment to be provided before the depression worsens ! Burnout, Stress, and Coping in Caregivers Burnout is believed to be a consequence of a broader feeling known as compassion fatigue (CF), that often develops among caregivers of trauma victims and/or patients with a grave illness, particularly after providing care for an extended period (Stamm, 2010). CF refers to the negative outcomes of being a caregiver to such individuals, and includes specific feelings such as exhaustion, frustration, depression, or even fear resulting from working with this population. In addition to burnout, the other outcome of CF is secondary traumatic stress (STS), resulting due to prolonged exposure to traumatized individuals, and manifesting as an ongoing combination of fear, intrusive imagery, and/or sleep disturbance. While caring for sick or traumatized individuals over an extended period can be mentally and emotionally draining, there is also the opportunity for personal reward stemming from knowing one has contributed to ameliorating the quality of life of another individual in a time of need. These positive feelings, known as compassion satisfaction (CS) are the opposite of CF, and refer specifically to the pleasure or fulfillment one feels from helping others, in particular those faced with illness or trauma, and carrying out this role well (Stamm, 2002). Unlike CF, CS does not break down into further subcategories. Stamm (2010), suggests that together, CS and CF represent a worker s overall professional quality of life. The Professional Quality of Life Scale (ProQoL) produces a rating of these two components. The coping strategies a caregiver uses to deal with the stresses associated with caring for traumatized and/or grievously ill patients may contribute to their level of CS or CF. However, the literature on specific coping strategies that contribute towards increased or decreased CS and/or CF is sparse. The coping strategies used may alter one s perception of the stresses faced on a daily basis, producing higher or lower levels of CS or CF. Understanding which specific coping strategies are associated with increased or decreased levels of CS and CF is important. This information can gauge which strategies increase the satisfaction one obtains from their caregiving role, and help to assess and provide suggestions to alter one s coping style when it is

25 11 known to reduce satisfaction and increase fatigue. Given that previous research has shown that a caregiver s mental state impacts the quality of care provided to patients (e.g., Beach et al., 2005), this research will contribute to the field by providing suggestions for appropriate coping styles to maximize CS and reduce CF ! Personality and Coping Personality, which is made up of the individual characteristics that shape a person s behaviour, feelings, and thoughts, has been linked with circadian rhythms and sleep quality (e.g., Cavallera, Gatto & Boari, 2014; Duggan, Friedman, McDevitt & Mednick, 2014; Hintsanen et al., 2014; Hsu, Gau, Shang, Chiu & Lee, 2012). In addition, personality has been linked with coping, such that certain coping styles occur in increasing or decreasing frequency with certain personality traits. Some research suggests that even prior to coping, one s personality predicts frequency of exposure to stressors, type of stressors experienced, and subsequent appraisals of the stressors. For example, neuroticism contributes to one s exposure to interpersonal stress, a tendency to classify events as highly threatening, and to feel unequipped with the necessary coping resources, while scoring higher on conscientiousness is reflective of lower stress exposure, likely due to advanced planning and impulse control (Carver & Connor-Smith, 2010). The idea that personality predicts stress exposure may be especially true in average daily life scenarios where one has some control over the roles he or she takes on, the interactions that may be had or avoided during the day, or the scenarios where a person may find themselves. However, this theory may not apply in scenarios where a person has less control over the stressor. Among cancer patients, lifestyle choices may at times contribute to the disease s development, but on the whole, people are equally susceptible to a cancer diagnosis in general, regardless of personality. Among familial or spousal caregiver, one s relationship with the cancer patient, and not personality, determines this role. In both these groups, personality will contribute to one s adjustment to the role, and their ability to cope with the stressors being presented. In these cases, it is important to understand how personality predisposes an individual to cope with stressors when they are presented. An individual s decision to work in oncology (either as an oncologist, oncology nurse, pharmacist, etc.), may be more so determined by personality compared to cancer patients and familial caregivers. This relates back to the previously mentioned point that personality may predispose people to find themselves in particular scenarios. However, in regard

26 12 to selecting a career, personality may contribute to one s reasons for taking on a paid caregiver role in the field of oncology, in addition to mediating how they will cope with the various stressors that will be presented in this career. In each of these cases, personality will affect how one copes with the stresses of their role. While research on coping strategies and personality traits among cancer patients, and spousal and oncology staff caregivers is sparse, studies conducted among the general population may serve as a starting point. Research has suggested various associations between personality traits and choice of coping strategies. Bartley and Roesch (2011) found that college students high in conscientiousness were more likely to engaged in problem-focused coping strategies (e.g., problem-solving, cognitive decision making) which in turn was associated with greater positive affect when faced with a daily stressor. In a meta-analysis assessing the relationship between coping and personality traits, high conscientiousness and extraversion were more common among individuals using problemsolving and cognitive restructuring, which generally reflects problem-focused coping strategies. Extraversion was also noted to produce support-seeking coping behaviours. This same analysis noted that neuroticism was more predictive of emotion-focused coping strategies, but also showed a link to support-seeking, similar to that found among individuals high in extraversion (Connor-Smith & Flachsbart, 2007). Among intensive care unit (ICU) nurses, while personality was not associated with workplace stress, it was linked with various coping styles used by the participants to approach daily stresses. Among nurses reporting greater conscientiousness and or agreeableness, there was a greater association with active coping to work towards making the situation better, and planning by using strategies to resolve a stressor. Nurses high in openness were also more likely to cope by using positive reframing in order to see stressors in a more positive light. These personalities showed associations with coping strategies indicative of problem focused coping to resolve the problem. Conversely, high neuroticism was strongly related to venting as a coping strategy to verbally express negative feelings, reflective of an emotion-based coping style aimed at reducing one s negative feelings about the threat as opposed to altering the source of stress itself (Burgess, Irvine & Wallymahmed, 2010). In the research discussed in this dissertation, in addition to assessing personality and coping in this cancer-related group, we addressed the role of personality among patients and caregivers as a mediating factor on the association between chronotype and sleep quality on coping, and one s ability to handle the stresses associated with their role, both across the day and overall.

27 13 Understanding the association between chronotype, sleep quality and personality and their influence on coping will allow for more tailored strategies to foster healthy coping strategies among patients and caregivers with different chronotypes and sleep patterns, as well as personality types. 1.3! Cancer as a Chronic Stress Stress results when the demands or outcomes of a positive or negative situation impinge upon or threaten one s behavioural, emotional, or physical state. More specifically, stress is deemed as an unpleasant negative emotional experience resulting in behavioural, biochemical, and physiological changes intended to adapt to the stressor, either via its manipulation, alteration, or accommodation (Baum, 1990). Stressors can be acute or chronic. Acute stressors are those that are specific episodic events with relatively discreet onset and offset points, and are general occurrences in everyday life (e.g., an interview, narrowly missing a car accident, etc.). Chronic stressors refer to ongoing events that continue over a prolonged period of time (e.g., poverty, long term illness). The body s stress response system is activated when dealing with acute and chronic stress to prepare the body for the challenges that must be faced. However, chronic longterm activation of this system at both a low or high stress level is detrimental to one s mental and physical health, contributing to a range of health problems varying in severity (e.g., high blood pressure, obesity, anxiety, and depression, etc.). Interestingly, events and factors that cause stress for one individual may not produce the same stresses for another person. Different people can react to stress in a variety of ways, with the distinction typically depending on one s perception of the stressor (e.g., can it be overcome, how will it affect life, etc.) (Baum, 1990; Hammen, Kim, Eberhart & Brennan, 2009). Cancer can be contributed to by the detrimental effects that stress causes on the body, and itself acts as a long-term chronic stressor to both the patient and his or her caregivers, including medical professionals, and friends and family members. For patients, the gravity and uncertainty of cancer overall causes stress, but various forms of cancer and the according treatments may cause their own specific stresses such as the loss of a body part, or changes in one s sexual functioning. For medical caregivers, being tasked with continuously providing care and assistance to ill individuals, coupled with being charged with their care and not always seeing

28 14 favourable outcomes produces a chronic stress. As friends and family members providing care, chronic stress can result for many reasons including constant worry for a loved one, and changes to one s own personal life including taking on a new role. In each case, one s personal coping strategies will determine how an individual will cope with and be affected by the stresses associated with cancer ! Emotional Distress in Patients It is well understood that in addition to the physical symptoms associated with breast cancer and its treatment, there are increased risks for developing psychological problems and suffering emotional distress (Barre, Padmaja, Saxena & Rana, 2015). Bultz and Carlson (2006) reviewed the literature and found that in North America the incidence of distress among cancer patients across the trajectory of the illness (diagnosis, treatment, survival, and or palliation) is between 35-45%. Emotional distress during these times can stem from a number of reasons such as worry about one s health and survival, changes in family life and or job, financial security, marital problems, etc. Research indicates that when cancer patients at large experience greater emotional distress, they are more likely to visit emergency facilities and community health services, thus placing a larger burden on the healthcare system, while often leaving the emotional distress unresolved (Carlson & Bultz, 2004). In addition to the economic burden that emotional distress can cause when patients seek additional emergency or community care, the emotional distress compounds with the physical symptoms patients may already be experiencing thus adding extra burden to the situation. While a certain level of emotional distress is normal, and a patient can still continue to function, emotional distress can often become all-consuming and debilitating. Emotional distress may stem from poor coping, and may also fuel continued poor coping styles. For these reasons, it is important to understand solutions to treat or alleviate emotional distress, and maximize positive, proactive, and healthy coping strategies among patients ! Why Choose Breast Cancer Patients Survival rates for patients diagnosed with stages I to III breast cancer have increased significantly in recent decades, with five-year survival rates between approximately 72% to almost 100% (Canadian Cancer Society, 2016b). While survival rates from breast cancer are increasing, incidence of breast cancer is still relatively high; it was estimated that in 2016 alone, approximately 25,700 Canadian women would be diagnosed with breast cancer (Canadian