INVESTIGATING THE TRANSITION FROM CHRONIC LOW BACK OR NECK PAIN TO WIDESPREAD PAIN AND FIBROMYLGIA By Lindsay Lancaster Kindler, MSN, RN, CNS A Dissertation Presented to Oregon Health & Science University School of Nursing In partial fulfillment of the requirements for the degree of Doctor of Philosophy April 14, 2009 ii ACKNOWLEDGEMENTS This dissertation research was supported by a National Institute of Nursing Research Institutional National Service Research Award (5 T32 NR007061-15), a National Institute of Nursing Research Individual National Service Research Award (1 F31 NR010301-01), the Oregon Health & Sciences University Dean’s Award for Doctoral Dissertation, the Sigma Theta Tau Beta Psi Research Award, and a University Club Foundation Fellowship Award. The generous funding provided by these institutions enabled the participants of this study to be compensated for their time and energy and allowed me to express my appreciation to several individuals who assisted with testing a subset of these participants for fibromyalgia. This funding also allowed me to present my research twelve times at various regional, national, and international conferences. Equally as important, this financial support paid for necessary research materials and services such as printing and mailing study surveys and invitation letters. Without the support provided to me by these considerate institutions, this research would not have been possible. Lastly, the generous award from the University Club Foundation will help me move into the next phase of my research career; a post-doctoral fellowship at the University of Florida. Although I alone will be receiving this doctoral degree, it should really include the names of the many individuals who made this journey possible. Throughout this program I have come to appreciate how fortunate I have been to have a committee whose primary interest is helping me succeed. Dr. Kim Dupree Jones has consistently been an incredible cheerleader whose faith in me has helped me believe in myself as well. Throughout my work with her, Kim has served as a role model to demonstrate that a woman can be a successful researcher while maintaining a family life and being a kind person to others. Dr. Robert Bennett’s expansive knowledge of the field has piqued my iii own interest in the biological mechanisms of chronic pain and fibromyalgia, pushing me to further my research in this area through a post-doctoral fellowship. Finally, I am grateful to Dr. Nancy Perrin for patiently sharing her statistical expertise, all the while never making me feel inept. Although Nancy’s skills are requested on much higher level projects, she treated me as if my study were just as critical to the advancement of the University. I am grateful to my committee for providing me with the support, expertise, and encouragement necessary to successfully complete this study. Throughout my time in the program I was fortunate enough to work clinically with an incredibly supportive and flexible team of coworkers at the Kaiser Permanente Pain Clinic. Their flexibility allowed me to continue the work that has been the impetus for my research interests and stay connected with the patients whose courage in the face of continuous pain moves us to find better treatments. The Pain Clinic has truly been a second family whose love and support kept me motivated to continue this journey. When I felt unsure of myself as a researcher, my coworkers reminded me that I was a valued clinician and had the ability to develop myself as a researcher as I had done with my clinical work. Their confidence in me has maintained my motivation throughout this journey. Finally, words cannot express the gratitude I feel towards the people who truly deserve this degree, my parents and husband. The support given to me by my parents astonishes me every day. Their unconditional belief in my abilities has allowed me to accomplish things I never thought possible. When I have doubted myself (as can occur regularly in a doctoral program), a simple phone call to them renewed my self confidence as I gain a glimpse of myself through their eyes. They are my biggest, most loyal fans, which has been invaluable throughout my journey. Finally, my husband, iv Travis, has met my seemingly unending journey in school with patience and understanding. He has endured the emotional ups and downs that come with waiting for grant approval, working with the IRB, patient recruitment, months of data entry, and preparation for conferences. He has kindly modified his expectations of a “normal” relationship as he has allowed me to focus on my own career development. And when I informed him of this thing called a post-doc, he put his own vision of our future on hold to support me in this endeavor. He has consistently demonstrated his love by allowing me to partake in the opportunities that advance my career, while placing his needs on the back burner. I am forever indebted to the people who made this journey not only possible, but enjoyable. You have given me an invaluable gift that I will never forget. v ABSTRACT Objectives: Emerging evidence suggests that chronic low back pain, chronic neck pain, widespread pain (WSP), and fibromyalgia (FM) share a common underlying mechanism, namely central sensitization. Research demonstrates that a majority of individuals with WSP and FM and some people with chronic low back or neck pain (termed chronic regional spinal pain, CRSP) exhibit altered pain processing which is characteristic of the neuroplastic changes of central sensitization. Perhaps due to this shared pathophysiology, recent studies have demonstrated that a subset of individuals with chronic low back or neck pain develop WSP and/or FM over time. Less clear are the specific risk factors that predispose a person with chronic low back or neck pain to the development of these widespread pain disorders. The purpose of this study was to determine the frequency with which patients with chronic low back or neck pain develop WSP or FM and to determine the risk factors which place a person at risk for this transition. Knowing the predictive factors for the development of WSP and FM in patients with CRSP is critical in that numerous studies have demonstrated that WSP and FM are associated with more severe clinical outcomes as compared to CRSP. Identifying a group of patients with CRSP who are at a higher risk of developing WSP or FM would provide an opportunity for the nursing and medical community to intervene in this downward trajectory. Methods: 2,256 patients previously seen by a multidisciplinary pain clinic in 2001 or 2002 for evaluation and treatment of a chronic low back or neck pain disorder were invited to participate in this study in 2007. The researchers used data collected on two questionnaires, one completed by the patients in 2001 or 2002 and one sent to them by the study team in 2007. Predictive factors investigated in this study fell broadly into three categories; features thought to influence the development of central sensitization, risk vi factors known to precede WSP and FM, and clinical features that frequently co-occur with WSP and FM. Both questionnaires included a body drawing, allowing the study team to determine which participants, who had CRSP in 2001 or 2002, had developed WSP by 2007. Those participants who had developed WSP by 2007 were invited to undergo an examination to evaluate the presence of a FM diagnosis. The 2001/2002 questionnaire was used to determine participant status on proposed risk factors prior to their development of WSP or FM. Results: Out of the 512 participants who had presented with CRSP in 2001/2002, 114 (22.3%) had developed WSP by 2007. Risk factors present in 2001/2002 that were associated with the development of WSP included moderate or severe pain intensity, female gender, history of abuse, family history of WSP, severe interference with general activity, morbid obesity, having one or more central sensitivity syndromes, and using more pain management strategies. Out of the 23.6% of subjects with WSP who were willing to report to the study site for an examination, 22 (75.9%) were diagnosed with FM. These 22 participants were added to the 18 participants who had been diagnosed with FM by their health plan provider between 2003 and 2007 for a total of 40 study participants who had presented with chronic low back or neck pain in 2001/2002 and developed FM by 2007. Risk factors present in 2001/2002 that were associated with a transition to FM included moderate or severe pain intensity, female gender, history of abuse, having a sibling with WSP, having one or more central sensitivity syndromes, and using more pain management strategies. Risk factors from 2001/2002 that did not significantly predict the development of WSP or FM in these participants with CRSP included depression, age, pain duration, number of back or neck surgeries, number of medication classes used to treat pain, tobacco pack year history, or receipt of disability benefits. vii Conclusions: This study demonstrated that nearly a quarter of patients with CRSP developed WSP over a six-year period. Interestingly, 75.9% if those participants who were willing to be examined also had FM. Several risk factors were shown to be predictive of the development of WSP and FM which allows practitioners to identify a group of patients with CRSP who are at increased risk for progression to a worsening clinical condition. Information gained from this study can guide the management of this group of high risk patients in an attempt to mitigate this progression. The identification of clinical features that are characteristic of this high risk group could also inform future studies that investigate individual differences in pain processing and prospective investigations into the development of other central sensitivity syndromes.