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Sleep and Wake Disorders Following Traumatic Brain Injury: Impact on Recovery of Cognition and Communication

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Sleep and Wake Disorders Following Traumatic Brain Injury: Impact on Recovery of Cognition and Communication Sleep and Wake Disorders Following Traumatic Brain Injury: Impact on Recovery of Cognition and Communication by Catherine Anne Wiseman-Hakes A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Graduate Department of Rehabilitation Science University of Toronto © Copyright by Catherine A. Wiseman-Hakes 2012 Sleep and Wake Disorders Following Traumatic Brain Injury: Impact on Recovery of Cognition and Communication Catherine Anne Wiseman-Hakes Ph.D. Reg. CASLPO Graduate Department of Rehabilitation Science University of Toronto 2012 Abstract Objective: To examine sleep and wake disorders following traumatic brain injury (TBI) and their impact on recovery of cognition, communication and mood. Research Design: This three-manuscript thesis comprises an introduction to sleep in the context of human function and development. It is followed by a systematic review of the literature pertaining to sleep and wake disorders following TBI, and then explores the relationship between sleep and arousal disturbance and functional recovery of cognitive-communication through a single case study, pre–post intervention. Finally, a larger study longitudinally explores the impact of treatment to optimize sleep and wakefulness on recovery of cognition, communication and mood through objective and subjective measures, pre-post intervention. The thesis concludes with a chapter that addresses the implications of findings for rehabilitation from the perspective of the International Classification of Functioning, Disability and Health (ICF), and a presentation of future research directions for the field Methods: The first manuscript involved a systematic review and rating of the quality of evidence. The second manuscript involved the evaluation of sleep and ii wakefulness by objective measures, and longitudinally by self-report through the Daily Cognitive-Communication and Sleep Profile (DCCASP, © Wiseman-Hakes 2008, see Appendix S). Cognitive-communication abilities were also measured by the DCCASP. The third manuscript utilized a single case series and cohort design to evaluate sleep and wakefulness, and to examine cognition, communication and mood at baseline and following optimization of sleep and wakefulness. Results: For Manuscript One, 43 articles were reviewed for levels and quality of evidence across 5 domains: epidemiology, pathophysiology, neuropsychological implications, intervention and paediatrics. In Manuscript Two, we showed that there was a statistically and functionally significant relationship between perceived quality of sleep and language processing, attention and memory, seen across the phases of the intervention. In Manuscript Three, we showed that there were statistically and functionally significant improvements across several domains of cognition, communication and mood in response to treatment. Conclusions: Sleep and wake disorders after TBI are pervasive, and can negatively impact rehabilitation and recovery. There is a need for systematic evaluation and intervention for these disorders in all persons with TBI. iii Acknowledgments The evolution of this thesis has been a journey that could not have been completed without the dedication and support of many people along the way. First, I express my sincere gratitude to my supervisor Dr. Angela Colantonio for her unwavering support, mentorship, patience and guidance throughout this process. It has been an honour to work with you and learn from you. To my advisors, Dr. Elizabeth Rochon and Dr. Rahim Moineddin, I thank you for your expertise, insights and contributions. Dr. Kimberly Cote of Brock University has been unfailingly gracious and giving of her time, expertise and mentorship. To Dr. Brian Murray, neurologist and director of Sleep Medicine at Sunnybrook Health Sciences Centre, thank you for the outstanding clinical care you provided for our study participants. You have been a mentor, co-investigator, and have become a good friend along the way. I offer my sincere thanks to Dr. Murray’s assistant, Richelle Bercasio, for all of her scheduling and juggling, and to Dana Jewell, chief technician in the sleep lab. Dr. Nora Cullen, physiatrist, and Sheila MacDonald, speech language pathologist and dear friend, thank-you for believing in the relevance of this study and for supporting me by referring your patients. I thank Dr. Chanth Seyone for his support during the early stages of the research. I am also grateful for the dedication of my work-study students, Reema Farhat and Alison Rozario. Charles Victor; for your help and support of my attempts at mastering statistics, I could not have done it without you! Lee Vernich, who managed all of my DCCASP data, your help has also been invaluable! I would like to thank Sandra Sokoloff for her friendship and help with administration and editing. Judith Gargaro, for your keen eye, dedication, sense of humour, and help: you have been an important part of this journey! I also thank my colleague Tatyana Mollayeva for her friendship, enthusiasm and expertise in reviewing the sleep findings. Michael Hutchison, thank-you for your generosity in developing the adobe DCCASP data collection and response forms, and for your friendship these past years, including our ‘coffee dates’ to support each other through the bumps, and celebrate the successes. I am grateful to have received financial support from the University of Toronto, Toronto Rehabilitation Institute, the Ontario Work Study Program and the Canadian Institutes for Health Research. iv To my wonderful study participants and your families, I thank you for letting me into your lives under difficult circumstances, and for teaching me as much I hope you have learned from being part of this study. You continue to inspire me and I dedicate this work to all of you. On a personal note, I wish to thank my mother, Janice Wiseman for her unfailing encouragement, and my husband Michael, for his tremendous support and the many dinners he cooked throughout these long years! Finally, to my three incredible teenagers (children when I began this journey!) Andrew, Hannah and Nicholas, thank you for bringing so much joy to my life. v Table of Contents Abstract ..................................................................................................................................................................... ii Acknowledgments ............................................................................................................................................... iv Chapter 1 Introduction ....................................................................................................................................... 1 1. Background .................................................................................................................................................... 1 1.1 Introduction to Cognitive-Communication Disorders ......................................................... 2 1.2 Introduction to Sleep Physiology................................................................................................. 4 1.3 Homeostatic and Circadian Control of Sleep Onset .............................................................. 8 1.4 Introduction to and Definition of Fatigue................................................................................. 8 1.5 Statement of the Problem ............................................................................................................... 9 1.6 Rationale for Present Study ........................................................................................................ 11 1.7 Objectives ........................................................................................................................................... 12 1.8 Roadmap of the Thesis.................................................................................................................. 12 Chapter 2 Sleep and Wake Disorders Following Traumatic Brain Injury: A Systematic Review of the Literature ...................................................................................................... 14 2. Abstract ........................................................................................................................................................ 14 2.1 Background and Introduction .................................................................................................... 15 2.1.1 Definition of Sleep and its Functions ............................................................................... 16 2.2 Methodology ..................................................................................................................................... 17 2.3 Results ................................................................................................................................................. 22 2.3.1 Previous Reviews of Sleep .................................................................................................... 22 2.3.1.1 Disorders and Insomnia Following TBI: An Historical Overview of the Literature to Date ............................................................................................... 22 2.3.2 Single Study Papers................................................................................................................. 26 2.3.2.1 Epidemiology .................................................................................................................... 28 2.3.2.1.1 Patients recruited from acute and post-acute care
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